International Business Strategy IBS Essay Example | Topics and Well Written Essays - 2500 words

International Business Strategy IBS - Essay Example It is proved that using the first mover advantage a firm can increase its competitiveness but the full success of this practice cannot be guaranteed, even for firms that are already established in their market. 2. International Business Strategy 2.1 The concept of first mover advantage - overview In the context of international business the first mover advantage theory can be related to the work of Markusen (2002). According to the above theorist, trade relationships are likely to be influenced by geography, meaning that businesses that are interested in entering the global market tend to prefer the markets of neighbouring countries, probably because risks and costs involved are expected to be lower (Sitkin and Bowen 2013). For FDI also a similar practice is used. Under these terms, the development of international business is based on two, critical, factors: a) learning effects; this term is used for showing the transfer of knowledge between ‘the research and development secto r of each business and its other sectors/ departments’ (Sitkin and Bowen 2013, p.38); this strategy of knowledge transfer decreases risks since no external intervention on knowledge used for building business strategy can occur; b) the first mover advantage; the specific concept reflects the following idea: ‘the first firm to enter a new market and leverage its existing experiences is in a good position to shut out future rivals’ (Sitkin and Bowen 2013, p.38). According to the above, the first mover advantage involves in ‘introducing in the market a new product or service’ (Cullen and Parboteeah 2013, p.273). However, the benefits of the above concept are related to the following term: that the product/ service employed ‘is not only innovative but also comprehensive’ (Cullen and Parboteeah 2013, p.273). The term comprehensive is used for showing a product/ service that ‘meets the customers’ expectations’ (Cullen and P arboteeah 2013, p.273); only such product/ service would be able to result to profits. The concept of first mover advantage, as described above can be effectively used for developing a business strategy in regard not only to the international market but also to the local market (McDonald and Burton 2002). The terms of such use of the specific concept are described analytically in the next section. 2.2 The use of the concept of first mover advantage in formulating a business strategy In regard to the use of the concept of first mover advantage in practice the following fact should be highlighted: the specific concept can be incorporated in different business strategies, meaning that it can be used as the basis for developing business strategies of various formats, depending on the needs of each organization, the resources available and the conditions in the business environment (Cullen and Parboteeah 2013). Figure 1 – Franchising based on the first mover advantage – the oretical model (source: Michael 2013, p.62) The study of Michael (2003) refers to the use of the first mover advantage as part of a franchising strategy. The involvement of the specific concept in a franchising strategy should be based on certain rules; the relevant framework is presented

Management Essay Example for Free

Management Essay Your safety is important, updates have successfully prepared the enclosed form to report identity theft to creditors. Would you mind going to our website to fill out the customer information so that your order can be processed with our new database software? We are now offering RapidAssist, a software program that provides immediate technical support through our website to your employees and customers. To provide better service, a new software named RapidAssist is now offered to provide you with immediate technical support from our website to employees and customers e. To provide you with easy access to the new parking lot, a new restriction policy has been activated for â€Å"A† vehicle permits. The credit union now prohibits the cashing of double –endorsed checks presented by our customers to make sure you don’t suffer monetary losses. Our warranty goes into effect when we have receive the product’s registration card from the purchaser to supply you guaranteed protections. To help better your systems, we will be shutting down both systems Thursday afternoon to install upgrades. Regarding your request, the items listed above (printer toner and supplies) are being sent to your Oakdale office, referring to your telephone conversation on April 1. Kindly inform the subscriber whether or not your spokesman will be making an appearance in the near future. c. It is outstanding that we still managed the contract after the customer increased his demands, however our manager responded with better transitions. By the way, we had some errors in the schedule but don’t have to erase everything and start from the beginning. To ease the confirmation of this agreement, your negotiators push that the membership respond in the favorable. Our head manager was upset because I was sick in the time of the team meeting.

Celine Dion :: Canada Canadian

Celine Dion Celine Dion is a proud Canadian, that is why she has sung our national anthom at countless events, that is why she financially supports numerous Canadian organizations, that is also why she continues to make french and english albums. She is a healthy role model for young and old people all over the world, and it is an honour to say she is Canadian. Celine Dion was born in Charlemagne, Quebec, on March 30, 1968 and was the youngest of 14 children in a large musical family. Celine Dion was named after a song her mother was singing while pregnant. She was discovered singing in the family owned restaurant, at age 12, but had been singing there ever since age five, along with her other siblings. It was a small restaurant and club where the children could often showcase their musical talents where her father would play the accordian and mother the violin. At only five years old, she had already began to develop as a singer and entertainer, so it makes sense she had the talent and capability to produce her very first recording at only age twelve with her mother and her brothers. Celine was discovered by Montreal Impresario, Rene Angelil, who later became her husband, in 1981. Celine's mother had found Rene's address in an album of Ginette Reno, a popular french singer. Rene had heard the demo-tape containing the songs Cel! ine had written (In particular "Ce N'etait Qu'un Reve"-or in english, "It was Only a Dream"), and he was immediatly taken by the voice of young Celine that he became determined to make her an internationally known talent. When he first heard her sing live, he cried because it was so beautiful. Rene had so much faith in Celine, that he even mortgaged his house to finance the production of Celine's debut album. Her only obstacle for success beyond Canada and France was her French lyrics. Record companies, as it turned out, were less enthusiastic of investing in a low-class preteen than Rene Angelil was. The financial support they needed to make Celine a success was not being produced, so they created a low budget Christmas album, "Celine Chante Noel," (Celine Sings Christmas), and another album, "Voix du bon Dieu," (The Voice of God). Celine released these singles at the young age of 13, yet they proved to be very successful. Even though these were low budget, people gave the albums a chance, and soon Celine had become the teen sensation of Quebec. Her early years also brought a string of awards, allowing

Thermodynamic Analysis and Performance Characteristics

AEROSPACE ENGINEERING SCHOOL OF MECHANICAL ENGINEERING AND DESIGN THE THERMODYNAMIC ANALYSIS AND PERFORMANCE CHARACTRISTICS OF A TURBOFAN JET ENGINE By J. E, Ibok 2011 Supervisor: Dr Lionel Ganippa ABSTRACT This work focuses on the performance analysis of a twin spool mixed flow turbofan engine. The main objective was to investigate the effects of using hydrogen, kerosene and natural gas fuel on the performance characteristics such as net thrust, specific fuel consumption and propulsive efficiency of the turbofan.Another aim of this work was to introduce the concept of exergy and thermoeconomics analysis for twin spool mixed flow turbofan engine and show the components that contributes the most to the inefficiency of the engine. A generic simulation was carried out using Gas Turb 11 software to obtain reasonable analysis results that were verified with a real-time JT8D-15A turbofan engine. The parametric analysis was done for constant value of mass flow rate of fuel and constant turb ine inlet temperature for all three fuels.The result were rightfully obtained for these analysis cases and discussed accordingly. Brunel University Mechanical Engineering Academic Session: 2010/2011 Name of Student: Johnson Essien Ibok Supervisor:Dr Lionel Ganippa Title: The Performance Characteristics and Thermodynamics Exergy and Thermoeconomics analysis of a Twin Spool Mixed Flow Turbofan Engine Operating at 30,000ft at M0 0. using Kerosene, natural Gas and Hydrogen Fuel. Abstract: This work focuses on the performance analysis of a twin spool mixed flow turbofan engine. A generic simulation was carried out using Gas Turb 11 software to obtain reasonable analysis results that were verified with a real-time JT8D-15A turbofan engine. The parametric analysis was done for constant value of mass flow rate of fuel and constant turbine inlet temperature for all three fuels.The result were rightfully obtained for these analysis cases and discussed accordingly. Objectives: The main aim of this work is to conduct the parametric cycle simulation of a twin spool mixed flow turbofan engine and investigate the performance characteristics of it. Another aim of this work is to show the effects of using hydrogen, Kerosene and natural gas fuel on the overall performance of the twin spool mixed flow turbofan engine.Also, the purpose of this work is to introduce the use of the second law of thermodynamics analysis known as exergy and thermoeconomics in analysis the twin spool mixed flow turbofan engine Background/Applications: This work is applicable in so many ways when it comes to the overall performance optimization and feasibility analysis of a jet engine. This work relates to the aerospace and aviation industries since the turbofan engine is amongst the vast number of jet engine used in propulsion of aircrafts.There is increasing pressure in the aviation industry to reduce pollution and depletion of energy resources while at the same time maintaining reasonable investment cost and high overall performance. Hence, this research was conducted in hopes of coming up with a new solution to this problem. Conclusions: The main conclusion drawn from the performance analysis is that hydrogen fuel produced the highest thrust level and the lowest specific fuel consumption between the three fuels for a constant mass flow rate of fuel.Kerosene fuel generated thrust level can be increased if it is mixed with a small amount of hydrogen. The Exit jet velocity ratio remained constant despite the increasing bypass ratio for all three fuels at constant mass flow rate of fuel. Using the exergetic analysis showed that the combustion chamber and the mixer contributed the most to the inefficiency of the turbofan engine. The amount of exergy transferred into the turbofan engine by hydrogen was depleted in the smallest ratio compared to natural gas and kerosene for constant mass flow rate of fuel.The thermoeconomics analysis showed that it is preferable to use local based co st evaluation to quantity specific thermoeconomics cost of thrust than the global method since the value was lower. Results: The results obtained from the simulation using Gas Turb 11 produced an error range of 0. 25% – 8. 5% when verified with the actual test data of the JT8D-15A turbofan engine. The results obtained for the analysis defined a reference design point at which the parametric analysis was conducted on. The analysis was done in three cases as shown clearly in the test matrix in table 1 below.Analysis| Parameters being varied| Parameters Kept Constant| Performance Characteristics| case 1| * Bypass ratio * Turbine Inlet temperature| * HPC Pressure Ratio * LPC Pressure Ratio * Fan Pressure Ratio| * Velocity ratio * Fuel-Air-ratio * Turbine inlet temperature * Net thrust * Specific Fuel Consumption * Thermal efficiency * Propulsive efficiency| case 2| * Bypass Ratio * Three different fuelsmH2mCH4mC12H23| * Mass flow rate of fuel * HPC Pressure Ratio * LPC Pressure R atio * Fan Pressure Ratio| | Case 3| * Bypass Ratio * Three different fuelsmH2mCH4mC12H23| * Turbine inlet temperature * HPC Pressure Ratio * LPC Pressure Ratio * Fan Pressure Ratio| | Table 1 The Test matrix of the Parametric Analysis. The exergy analysis was done for the parametric analysis of case 2 and case 3 where the exergy destruction rates, exergetic efficiency, exergy improvement potential rate and fuel depletion ratio were calculated. The distribution of these results throughout each component of the turbofan engine was represented with bar charts and Grassmann diagram. The thermoeconomics analysis was conducted for analysis case 2 using kerosene fuel.The specific thermoeconomics cost of thrust was calculated using global and local based cost evaluation methods. ACKNOWLEDGEMENTS First of all, I would like to thank my parents for their financial support and encouragement because without them I would not be here and be able to do this work. I am deeply thankful to my supervi sor, Dr Lionel Ganippa for believing in me and giving me the opportunity to work with him in this field of study. I am also thankful to him for giving the necessary guidance and advice and his enthusiasm and innovative ideas inspired me. Finally, I would like to thank Mr Joachim Kurzke for providing me with the necessary software needed for my dissertation. Table of ContentsAcknowledgements i Contents ii List of Notations and Subscripts iv List of Tables vi List of Figures vi Chapter 1: Introduction1 1. 1. Aims and Objectives2 1. 2. Computational Modeling3 Chapter 2: Jet Engines4 2. 1. Performance characteristics4 2. 1. 1. Thrust4 2. 1. 2. Thermal Efficiency5 2. 1. 3. Propulsive efficiency5 2. 1. 4. Overall efficiency6 2. 1. 5. Specific Fuel Consumption6 2. 2. Fuel and Propellants For Jet Engines7 Chapter 3: Turbofan Jet Engines †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ †¦8 3. 1. Introduction 8 3. 2. Classification of Turbofan Engines9 3. 3. Major Components of a Turbofan Engine10 3. 3. 1. Diffuser10 3. 3. 2. Fan and Compressor11 3. 3. 3. Combustion Chamber12 3. 3. 4. Turbine13 3. 3. 5. Exhaust Nozzle14 3. 4.Thermodynamic Process and Cycle of a Twin Spool Mixed Flow Turbofan Engine15 Chapter 4: Mathematical and Gas turb 11 Modeling of the turbofan Engine18 4. 1. Station Numbering and Assumptions18 4. 2. Design Point Cycle Simulation of the Turbofan Engine18 4. 3. Off-design Point Cycle Simulation of the Turbofan Engine21 4. 3. 1. Module/Component Matching 22 4. 3. 2. Off-Design Point Component Modeling22 Chapter 5: Methodology, Results and Discussions26 5. 1. General Relationship equations of the Major Parameters27 5. 2. Results and Discussions of Parametric cycle Analysis of Case 129 5. 3. Results and Discussions of Parametric Cycle Analysis of Case 235 5. 4.Results and Discussions of Parametric Cycle Analysis of Case 343 Chap ter 6: Exergy and Thermoeconomics Analysis of the Turbofan Engine49 6. 1. Exergy Analysis49 6. 1. 1. Exergy Analysis Modeling 50 6. 1. 2. Exergy and Energy Balance Equations of the Components58 6. 1. 3. General Relationships in Exergetic Analysis of the Turbofan Engine60 6. 1. 4. Results and Discussions61 6. 1. 5. Grassmann Diagram72 6. 2. Thermoeconomics Analysis74 6. 2. 1. Thermoeconomics Analysis Modelling74 6. 2. 2. Global Based Cost Evaluation76 6. 2. 3. Local Based Cost Evaluation77 6. 2. 4. Results and Discussion of the Thermoeconomics Analysis78 Chapter 7 Conclusions and Future Work80 Reference Appendix A Exergy Analysis Results Appendix B Thermoeconomics Analysis resultsList of Notations and Units ?| Isentropic efficiency| ?| Total Pressure ratio| m| Mass Flow Rate (kg/s)| f| Fuel/Air Ratio| M| Mach Number| Pt| Total pressure (kPa)| Tt| Total Temperature (K)| NCV| Net Calorific Value (MJ/kg)| Ht| Total Enthalpy (kJ/kg)| V| Velocity (m/s)| ?| Bypass Ratio| T| Static Temperat ure (K)| P| Static Pressure (kPa)| N| Actual Spool Speed (RPM)| Nc| Corrected Spool Speed (RPM)| mc| Corrected Mass Flow Rate (kg/s)| R| Universal Gas Constant (kJ/kmolK)| ?0| Standard Chemical Exergy (kJ/kmol)| Ex| Exergy Rate (MW)| xi| Mole Fraction| cp| Specific Heat at Constant Pressure (kJ/kgK)| ?| Ratio of Chemical Exergy to NCV| ?| Exergetic Efficiency| | Fuel Depletion Ratio| W| Power Rate of Work done (MW)| List of Subscripts| | LPT| Low Pressure Turbine| HPT| High Pressure Turbine| CC| Combustion Chamber| HPC| High Pressure Compressor| LPC| Low Pressure Compressor| d| Diffuser| noz| Nozzle| mix| Mixer| dest| Destruction Rate| 0, ambFAR| Ambient conditionFuel-Air-Ratio| CH| Chemical| PH| Physical| KN| Kinetic| PN| Potential| IP| Exergy Improvement Potential Rate (MW)| CRF| Cost Recovery Factor| c| Specific Thermoeconomic Cost (MJ/kg)| STD| Standard Temperature and Pressure| TIT| Turbine Inlet Temperature| TSFC| Thrust Specific Fuel Consumption (g/kNs)| SFC| Specific Fuel Co nsumption| p| Propulsive| TH| Thermal|O| Overall| T| Thrust| equip| Equipment| PEC| Capital Cost of Equipment| List of Tables Table 1 input parameters for Design Point Cycle Simulation on Gas Turb 1119 Table 2 Comparison table for the Actual Test Data and Simulated Data using gas Turb 1121 Table 3 Comparison Table for Actual Test Data and Simulated Off-Design Point data Using gas Turb 11. 25 Table 4 Equivalence Ratio of the three Fuels Combustion Processes†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 62 Table 5 Assumed Capital costs of Each Component of the Turbofan Engine. 75 Table 6 Flow of Specific Thermoeconomics Cost in all the Components 79 List of Figures Figure 1 Classification of Turbofan Engine9Figure 2 Layout of Forward Fan Twin Spool Mixed Flow Turbofan16 Figure 3 T-S Diagram for the Forward Fan Twin Spool Mixed Flow Turbofan17 Figure 4 Design Point Cycle Simulation Algorithm Using Gas Turb 1120 Figure 5 Example of a Compressor Performance Map/Cu rve24 Figure 6 Effects of Varying Bypass Ratio at Constant Values of TIT on Fuel-Air-Ratio30 Figure 7 Effects of Varying Bypass Ratio at Constant Values of TIT on Exit Velocity Ratio30 Figure 8 Effects of Varying Bypass Ratio at Constant Values of TIT on LPT Exit Pressure Ratio31 Figure 9 Effects of Varying Bypass Ratio at Constant Values of TIT on Net Thrust32 Figure 10 Effects of Varying Bypass Ratio at Constant Values of TIT on Specific Fuel Consumption33 Figure 11 Effects of Varying Bypass Ratio at Constant Values of TIT on Propulsive Efficiency34 Figure 12 Effects of Varying Bypass Ratio t Constant Values of TIT on Thermal Efficiency35 Figure 13 T-S diagram of using Hydrogen Fuel when the bypass Ratio is increased36 Figure 14 Variation of Fuel-Air-Ratio with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels37 Figure 15 Variation of TIT with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels37 Figure 16 Variation of Exit Velocity Ratio with Byp ass Ratio at Constant Fuel Flow Rate using three different Fuels38 Figure 17 Variation of LPT Exit Pressure Ratio with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels39 Figure 18 Variation of Net Thrust with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels40 Figure 19 Variation of Specific Fuel Consumption with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels41 Figure 20 Variation of Thermal Efficiency with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels42 Figure 21 Variation of Propulsive Efficiency with Bypass Ratio at Constant Fuel Flow Rate using three different Fuels43 Figure 22 Variation of Fuel-Air-Ratio with Bypass Ratio at Constant TIT using the three Different Fuels44 Figure 23 Variation of Exit Velocity Ratio with Bypass Ratio at Constant TIT using the three Different Fuels44 Figure 24 Variation of LPT Exit Pressure Ratio with Bypass Ratio at Constant TIT using the three Different Fuels45 Figure 25 Variation of Net Thrust with Bypass Ratio at Constant TIT using the three Different Fuels46 Figure 26 Variation of Specific Fuel Consumption with Bypass Ratio at Constant TIT using the three Different Fuels46 Figure 27 Variation of Propulsive Efficiency with Bypass Ratio at Constant TIT using the three Different Fuels47 Figure 28 Variation of Thermal Efficiency with Bypass Ratio at Constant TIT using the three Different Fuels48 Figure 29 Variation of Exergy Destruction Rate Using the three Fuels for Analysis Case 262 Figure 30 Variation of Exergy Destruction Rate Using the three Fuels for Analysis Case 364 Figure 31 Variation of Exergetic Efficiencies Using the three Fuels for Analysis Case 266 Figure 32 Variation of Exergetic Efficiencies Using the three Fuels for Analysis Case 367 Figure 33 Distribution of Exergy Improvement potential Rate Using the three Fuels for Analysis Case 268 Figure 34 Distribution of Exergy Improvement potential Rate Using the three Fuels for Analysis Case 369 Figure 35 variation of Fuel Depletion ratio using the Three Fuels for Analysis Case 270 Figure 36 variation of Fuel Depletion ratio using the Three Fuels for Analysis Case 371 Figure 37 Grassmann Diagram for the Exergetic analysis of Case 2 using kerosene Fuel for the Turbofan engine. 72 Chapter 1 Introduction Jet engines are complex thermodynamic systems that use a series of non-linear equation to define their thermodynamic processes and they operate under the principle of Brayton cycle.Brayton cycle is a cycle that comprises of the compressor, combustor and turbine working as a unit. Additionally, the major parameters that dictate the operational conditions of the engine at any point during the process are the relative altitude and Mach number. Mach number is the ratio of the velocity of the jet engine to the speed of sound. Basically, the main purpose of this type of thermodynamic system in aerospace industry is to accelerate a jet of air and as a result, generate enough thrust needed for flight. In addition, the design of jet engines is dependent of what purpose it will be used for in order to derive its maximum performance.For instance, in military application, jet engines are required to generate maximum thrust in minimum response time which consumes a lot of fuel whereas commercial jet engines are required to less noise generative, less fuel consuming and at the same time have high overall efficiency (El-sayed, 2008). There are certain factors that jet engine manufacturers take into consideration when designing jet engines which are the operating cost, engine noise, environmental emissions, fuel burn and overall efficiency. Accordingly, this has caused a global market competition for engine manufacturers like Rolls Royce, Pratt and Whitney, General Electric and CFM on who can produce the most efficient jet engines.In fact, Pratt and Whitney Company is working on a geared turbofan jet engine that they believe will reduce fuel burn, produce lesse r noise and emit less toxics while General Electric is coming up with simpler â€Å"ecore† jet engines that will be more fuel efficient than the current jet engines with as much as almost two fifths of current jet engines (Cassidy, 2008). Taking all that has been said into consideration, it can easily be asserted that by reducing the fuel consumption of the jet engine, the total temperature at the turbine blades will reduce thereby increasing the operating life and overall efficiency of the engine. Also, the total cost of the engine can be cut down. Indeed, Dr Pallan cited in (Ward, 2007) stated that reducing the fuel consumption by as little as 1% is highly longed after by engine manufacturers and this can result in very significant increase in the overall performance.In a general point of view, it can be said that the maximum point of achievement for jet engine manufacturers would be to design an engine that consumes the minimum amount of work in the compressor unit while g enerating the maximum amount of work in the turbine unit at minimum fuel supply. The main purpose of this work is to analyse the thermodynamic processes and performance of a jet engine using a simulation tool, exergy and thermoeconomics concept. 1. 1. Aims and Objectives The main objective of this work is to carry out the thermodynamic analysis and show the performance characteristics of a turbofan jet engine. In this work, the vivid explanation of the thermodynamics processes and cycle of each component of the turbofan engine starting from the diffuser to the nozzle will be covered. Also, the first and second law of thermodynamics with other laws will be applied extensively throughout this work.However, in the aspect of performance characteristics of the turbofan engine, a generic simulation will be carried out on a twin spool mixed flow turbofan engine. To relate this work to real life application, a JT8D-15A turbofan engine manufactured by Pratt and Whitney Company will be used a s the twin spool mixed flow turbofan for the simulation using the original design data. Indeed, the simulation tool that will be used is GasTurb 11 which was designed by Joachim Kurke and for more details on how it works can be found in (Kurke, 2007). This work will use the reference design point of the twin spool mixed flow turbofan at sea level with maximum take-off thrust to obtain the operating point of 30,000ft at M0 0. using the off-design performance simulation which will serve as the operating design point for the analysis in this work since the engine will spend most of its time in the cruise phase between 30000ft to 38000ft. The purpose of carrying this generic simulation of the turbofan engine is to investigate the effects of varying bypass ratio and turbine inlet temperature (thermal limit parameter) on the performance characteristics of the turbofan engine. In other words, the parametric cycle studies of the turbofan engine. This investigation will be done for three dif ferent cases which case 1 will be studying the effects of varying bypass ratio and turbine inlet temperature on the performance characteristics of the turbofan engine when some of the design choices are kept constant.The second case of study will be the comparison of the performance characteristics of the turbofan engine when three different fuels (kerosene, natural gas and Hydrogen) are used at the same mass flow rate using the same design point in case 1. Finally, the third case of study will be the comparison of the performance characteristics of the turbofan engine when the three fuels are undergoing the same combustion process that is constant turbine inlet temperature for the design point in case 1. This aspect of this analysis is very important owing to the growing problem of greenhouse effect and depletion of energy resources. In fact, statistics by the intergovernmental panel shows that aerospace industry is amongst one of the fast growing sources of greenhouse effect and t hat the emission of carbon dioxide will increase to five times what it is presently which is 3% (Symonds, 2005).Based on this, using alternative fuels like hydrogen and natural gas can tend to reduce pollution and consumption of energy resources risk and this work aims to show how that can be achieved while the overall efficiency of the engine is still high. Another approach of analysis in this work will be the use of the second law of thermodynamics analysis also known as exergy and thermoeconomics. This aspect of analysis of the turbofan engine will be done for the parametric analysis of case 2 and case 3 in efforts to also compare the three fuels that are being considered and show which fuel will cause the turbofan engine components to be most inefficient or have the most irreversibility.This analysis will be done by calculating the exergy relationships such as exergy transfer rates, exergy destruction rates, exergetic efficiencies, exergy improvement potential rates, and fuel de pletion ratios. Furthermore, the exergy analysis will be represented in a Grassmann diagram for parametric analysis case 2 of study. However, as for the thermoeconomics analysis of the turbofan engine, only parametric analysis case 3 studies will be done for only kerosene fuel and this work will aim to show how to use concept of local and global evaluation of thermoeconomic cost. 1. 2. Computational Modelling It will be very expensive and time wasting to design and develop new aircraft engine whenever an optimization or analysis wants to be done.In fact, Caoa Y, Jin, Meng and Fletcher (2005) stated that new ways should be developed to reduce aircraft engine design, maintenance and manufacturing cost in order to have effective worldwide market competition. Surprisingly, computer modelling is one approach of reducing manufacturing cost and time wasting. Computational modelling can simply be defined as the use of computer codes to replicate a typical system using some of its original d ata in order to analyse the system at varying conditions. The other side of the medallion shows simulation. There are many types of simulation tools normally used in simulating gas turbines such as Matlab/simulink, Modelica, Gas Turb 11, NPSS and many more. However, the simulation tool that will be adopted for the purpose of this dissertation is Gas Turb 11 designed by Joachim Kurzke.Gas Turb 11 is a language oriented program with a command prompt that calculates the output data without using block diagrams or graphical interface. It is user friendly in a sense that it is easy to find the tools library and to substitute data in for simulation. The Gas Turb 11 is specifically designed for simulation of all kinds of gas turbines starting from power generators to jet engines. Gas Turb 11 usually carries out two types of analysis which are the on design cycle point simulation and off-design cycle point simulation. Engine design point cycle simulation involves the study of comparing gas turbines of different geometry. This cycle design point must be defined before any other simulation can be done.On the other hand, off-design performance cycle point simulation involves the study of the behaviour of a gas turbine with known geometry. This cycle outlines the performance characteristics of each component such as performance maps, Overall efficiency. The type of simulation that will be done in this dissertation will involve the off-design and design point cycle. Chapter 2 Jet Engines 2. 1. Performance Parameter of Jet Engines 2. 2. 1. Thrust Thrust is the way of quantifying the ability of a jet engine to effectively utilise the energy added to it in order to propel or push itself forward in the opposite direction of the exiting jet in the exhaust nozzle.In other words, it is the reactive force to the force imparted by the exiting jet in the nozzle in accordance to Isaac Newton’s third law of motion. It is the most important parameter that has to be obtained for any jet engine and it depends heavily on the ingested mass of air, exiting velocity and pressure, the area of the nozzle, the flight velocity and ambient conditions. In fact, the mathematical expression for thrust which incorporates these factors is shown below as. Thrust=meVe-m0V0+Pe-P0Ae Where, e=the exit conditions at the exhaust nozzle, 0=ambient conditions at the inlet me=m0+mfuel Momentum Thrust=meVe; This is the thrust obtained from the reaction of the hot exhaust gases high velocity.Momentum Drag= m0V0 ; This the friction or drag force caused by the high velocity ingestion of air mass at the inlet. Pressure Thrust=Pe-P0Ae; This force is generated as a result of the higher exit static pressure compared to the ambient pressure which pushes back at the engine. Gross Thrust=meVe+Pe-P0Ae; It is the maximum obtainable positive thrust a jet engine can have when the drag forces are ignored. Special Cases of Thrust Take-off Thrust It is the thrust a jet engine can generate with its o wn power at static or low power setting which means the momentum drag component of thrust is ignored and the power of the engine at this point is equivalent to zero.This can be used to explain why the thrust of an engine at take-off condition is usually higher than at cruise condition since there is no momentum drag and effects of varying ambient condition. This only applies to turbojet, turbofan, and turboprop jet engines but when it comes to ramjet and scramjet, the air flow has to be accelerated by a booster system before it can start producing a positive take-off thrust. Pressure Thrust Component This is the thrust generated as a result of the static pressures of the exiting jet and ambient environment. In ideal cases where the nozzle has perfectly expanded the jet exit pressure to that of the ambient condition, the pressure thrust component will disappear which this case is not possible in reality.However, if the nozzle is choked which indicates that the ambient pressure is low er than the exit pressure of the jet, the pressure thrust component will have a positive effect on the net thrust. Also, if the nozzle tends to over expand the jet because of low energy addition to the jet and the exit pressure is lower than the ambient pressure, the pressure thrust component will have a negative effect on net thrust. 2. 2. 2. Thermal efficiency It is simply the measure at which energy in the engine system is converted. In other words, it is the measure at which total energy supplied to the engine system as heat transfer is converted to kinetic energy.In another way, it can easily be said to be the ratio of the power generated in the engine airflow to the rate at which energy is supplied in the fuel. ?TH=Power Generated in the Engine AirflowRate of Energy Supplied in the Fuel =12? meVe2-12? m0V02mfuel? NCV 2. 2. 3. Propulsive efficiency It is a measure at which kinetic energy possessed by air as it passes through the engine is converted into power of the propulsion of the engine. In mathematical terms, it is simply known as the ratio of thrust power to the power generated in the engine airflow. ?p=Thrust PowerPower Generated in the Engine Airflow = T? V012? meVe2-12? m0V02 2. 2. 4. Overall EfficiencyAs the name overall depicts, it is the resultant efficiency of a jet engine can have which is simply the product of the thermal and propulsive efficiencies. In mathematical terms, it is represented as shown below. ?O=? TH p =12? meVe2-12? m0V02mfuel? NCV? T? V012? meVe2-12? m0V02 =T? V0mfuel? NCV 2. 2. 5. Specific Fuel Consumption Specific fuel consumption as any other performance characteristics is a ratio and surprisingly it has a major effect on the economics of the aircraft as it is used to determine the aircrafts flight ticket costs. Specific fuel consumption has different expressions depending on what type of jet engine it is. For instance, in ramjet, turbojet and turbofan jet engines, it is the measure of the fuel mass flow rate to the thrus t force generated.Also, it is sometimes called the thrust specific fuel consumption (TSFC). TSFC=mfT However, in turbopropeller jet engines, it is the ratio of the fuel mass flow rate to the power generated in the engine shaft by the turbomachinery. It is sometimes referred to as the brake-specific fuel consumption (BSFC). TFSC=mfSP 2. 2. Fuel and Propellants for Jet Engines Fuels can implicitly be defined as substances used to add heat energy to a system through combustion or other processes. Fuels are mostly hydrocarbons like kerosene, diesel, petrol, alcohol, paraffin and butane and can also be in the form of individually free reactive molecular substances like hydrogen or chemical composites like natural gas, coal, wood.The gaseous state substances used as fuels such as hydrogen, and natural gas (94% methane and 6% ethane) are usually made into a cryogenic state as in liquefied at very low temperature because of their low boiling point. It can easily be asserted by anyone that t he only purpose that fuels have in jet engines is to add energy but little do they know that the purposes grows as the speed of the aircraft increases. For instance, Kerrebrock (2002) stated that supersonic aircrafts which attains very high stagnation temperature that can create destabilization to the airframe structure, engine component and organic substances like lubricants, uses its fuel as a coolant to this parts or components.The energy added by the fuel burned per unit mass of air flow is called the heating value of the fuel and it is a very crucial parameter to be defined before any combustion process analysis is done on a jet engine since it shows how complete the combustion process is through efficiency. The heating value can either be said to be higher or lower depending on if the water product of combustion is a vapour or a liquid. Since the combustion process in jet engine produces vaporised water, the lower heating value of the fuel is used. The most frequently used fue ls for jet engines are kerosene jet A1, A2, JP10 and many more but diesel can also be used. The disadvantages of these fuels are their inevitable emission of toxic substances that contribute to greenhouse effect and their risk of depletion.Accordingly, this has been the driving force for the use of alternative fuels such as cryogenic hydrogen and natural gas which is believed will reduce toxic emissions. Besides, hydrogen is a carbon-free energy carrier and possesses almost no risk of toxic emission since most of its combustion product will be water Chiesa and Laozza (2005). Chapter 3 Turbofan Jet Engine 3. 1. Introduction Between 1936 and the next decade when turbofan engines were invented, people showed little or no interest in them as they described them to be a complicated version of a turbojet engine. However, in 1956, the benefits of turbofan engines started to be noticed as major companies like Rolls-Royce and General Electric began manufacturing them.Since then, it is been o ne of the most used jet engine for commercial purposes because of its low fuel consumption and less noise production. In fact, it has been concluded to be the most reliable jet engine ever manufactured El –Sayed (2008). The turbofan jet engine gas generator unit comprises of a fan unit, compressor section, combustion chamber and turbine unit. Fundamentally, a turbofan jet engine operates as a result of the compressors pressuring air and supplying it afterwards for further processing. The majority of the pressurised air is bypassed around the core of the engine through a duct to be mixed or exhausted whereas the rest of it flows into the main engine core where it combusts with the fuel in the combustion chamber.The hot expanded gas products from the combustion process passes through the turbine thereby rotating the turbine as it leaves the engine. Consequently, the rotating turbine spins the engine spool which in turn rotates the other turbo machinery in the engine. This cause s the front fan to pressurise more and more air into the engine for the process to start all over again in continuous state. The turbofan engine is believed to be the perfect combination of the turboprop and turbojet engine and as a result, its advantages are usually compared to that of the turboprop and turbojet. In fact, Kerrebrock (1992) said that turbofan engine provides a better way of improving the propulsive efficiency of a basic turbojet.It is asserted that at low power setting, low altitude condition and low speed, the turbofan engine is more fuel efficient and has better performance than a turbojet engine. Unlike turboprop engine where vibration occurs in the propeller blades at relative low velocities, the fan in the turbofan engine can attain high relative velocities of Mach 0. 9 before vibration occurs. Also, since the fan in turbofan engines has many blades, it is more stable than the single propeller so even if the vibration velocity is reached, the vibration will not destabilize the airflow because the vibrations are almost negligible. Since the flow into the diffuser of the turbofan is usually subsonic, there very slim chances of shock waves being developed at the entrance. 3. 2. Classification of Turbofan EnginesThere are various types of turbofan engine ranging from high and low bypass ratio, afterburning and non-afterburning, mixed and unmixed flow with multi-spool, after fan and geared or ungeared. The classification of the various types of turbofan engines is shown below in figure 1. Nonetheless, the type of turbofan engine that would be used for the purpose of this dissertation is a forward fan two spool mixed flow turbofan engine. This type of turbofan engine was chosen because it is the compromise of a simple and complex turbofan engine. This is said because it comprises of almost all the classes of a turbofan which are low bypass ratio, forward fan with mixed flow, twin spool with ungeared fan.Moreover, because of the mixed flow intro duced, it produces additional thrust in the hot nozzle compared to the high bypass and it can also permit the addition of afterburner which produces a lot of thrust while consuming a lot of fuel which makes it suitable for military application which shows little worry on fuel consumption. In essence, carrying out a study on this type of turbofan engine will be of great relevance to the military air force sector especially if new research is discovered. TURBOFAN ENGINES Low Bypass Ratio Aft Fan Forward Fan Nonafterburning Afterburning High Bypass Ratio Geared Fan Single Spool Short Duct Ungeared Fan Two Spool Mixed Fan and Core Flow Unmixed Flow Long Duct Three SpoolFigure 1 Classification of Turbofan Jet Engines (El-sayed, 2008) 3. 3. Major Components of Turbofan Engine 3. 4. 1. Diffuser or Inlet Diffuser is the first component that air encounters as it flows into the engine. Basically, the purpose of a diffuser is to suck in air smoothly into the engine, reduce the velocity of the air, increase the static pressure of the air and finally, supply the air in a uniform flow to the compressor. Given the fact that overall performance of an engine is highly dependent on the pressure supplied to the burner, it is necessary to design a diffuser that incurs the minimum amount of pressure loss.To demonstrate this, Flack (2005) stated that if the diffuser incurs a large total pressure loss, the total pressure in the burner will be reduced by the compressor total pressure ratio time this loss. In other words, a small pressure drop in the diffuser can translate into a significant drop in the total pressure supplied to the burner. Another point taken into consideration when designing a diffuser is the angle because if the angle is too big, there will be tendency of eddy flow generation due to early separation. The major causes of pressure losses in the diffuser are as follows. First, losses due to generation of shock waves outside the diffuser and it majorly occur in super sonic diffusers.Secondly, the loss due to the unfavourable or adverse pressure gradient of the diffuser geometry which makes the flow separate a lot earlier and generates eddies. This separation causes a convergent area which makes the velocity not to be reduced by much. Due to the separation, the wall shear deteriorates the static pressure even further. Further analysis done by El-Sayed (2008), describes ways of accounting for this losses like using Fanno line flow and combined area and friction. Thermodynamic Process Equation In this analysis, the loss due to heat transfer is negligible so the process can be adiabatic. The initial kinetic energy is used to raise the static pressure p0 to the total pressure ? =pt2pt0 (inlet pressure recovery) efficiency ? d=IdealReal=ht2s-h0ht2-h0 assuming the gas is ideal and the specific heat at constant pressure is constant efficiency ? d=Tt2s-T0Tt2-T0 simplifying the equation given that ht0=ht2=ht2s and Tt2=Tt0and pt2s=pt2 TtT0=1+? -12M02 and T tT0=ptp0? -1? pt2p0=1+ ? d? -12M02 -1 3. 4. 2. Fan And Compressors Compressor is a very crucial component for the operation of an engine in the sense that it prepares the air for the combustion process in the burner. The main purpose of a compressor as the first rotating component is to use its rotating blades to add kinetic energy to the air and later translate it into total pressure increase.There are basically two types of compressors which are the centrifugal and the axial compressor. Firstly, centrifugal compressor as the name implies changes the direction of an axial airflow to a radial outflow of the air. It was the early compressors adapted in jet engines. It comprises of three main parts which are the impellers, the diffusers and the compressor manifold. The purpose of the impeller is to change the direction of the flow from axial to radial and at the same time increases its static pressure. The diffuser slows down the airflow and further increase the static pressure as it is supplied axially by the compressor manifold to the combustion chamber.The centrifugal compressor is advantageous because the cost of manufacturing it is low compared to axial compressor and as a result is suitable for small engines like turboshafts and turboprops. It is also advantageous because the pressure ratios at single stage are higher than that of the axial compressor. The centrifugal compressor has the tendency of attaining low flow rates and as a result is ideally suitable for helicopters and small aircrafts which require low flow rates. On the other hand, the centrifugal compressor cannot attain high pressure ratio and so it is not suitable when high peak efficiency is required. It incurs a lot of losses due to the change in direction. Secondly, an axial compressor is the most reliable type of compressor and is usually applied when higher pressure ratios of up to 40:1 are required.An axial compressor does not change the axial flow direction of the air but increases the total pressure. Indeed, an axial compressor comprises of three major components which are the rotor with blades, stator can and the inlet guide vane. A stage is a combination of a stator and a rotor. The assembly of the full rotor blade and stator can form the number of stages in a compressor and the greater the number of stages, the higher the total pressure ratio. In this arrangement, the air flows into the inlet guide vane and then into the rotor and stator assembly where compression starts. Also, the length of the rotor and stator reduces along the whole unit which signifies a reduction in volume which induces the increase in pressure.A fan or low pressure compressor is a type of axial compressor but the only differences are that the blades are longer, the total pressure ratio is lower than the typical compressor and the number of stages is usually 1 or 2. The main purpose of creating a fan is to compress more air and to create a bypass air which can be used to generate addition thrust or used for mixing process. Fan Equation Process Given that, isentropic efficiency ? fan= Ideal CycleActual cycle=ht3s-ht2ht3-ht2 Since the specific heat is constant, the equation deduces to ? fan=Tt3s-Tt2Tt3-Tt2 Simplifying the equation whenpt3s=pt3, Tt3sTt2=pt3pt2? -1? , ? fan=pt3pt2 and ? fan=Tt3Tt2 ? fan=? fan? -1? -1? fan-1 Bypass Ratio=msma where ms is the bypass flow rate and ma is the engine core flow rate.For the high pressure compressor, the equations remain the same as that of the fan except the changes in station numbering and the bypass ratio. 3. 4. 3. Combustion Chamber/ Burner The combustion chamber as the Brayton cycle implies is the only source of heat energy addition to the system. Accordingly, the combustion chamber causes very significant increase in the temperature of the air which results in the air gaining enormous internal energy. This energy gained is extracted to be used to power the turbine while the rest is used to create highly accelerated gases from the nozzle. There are three types of combustor namely; the can combustor, the annular combustor and the cannular combustor.The main considerations when designing a combustion chamber is to ensure that the combustion process is complete with no fuel waste, the combustor should have long life materials because any failure can lead to engine explosion. The other consideration is that the air must be heated enough above the ignition fuel temperature in order to ensure stoichiometric combustion. Equations of the Combustion Chamber In the real process of the combustor, total and static pressure drops and the temperature also drop. The major causes of pressure losses are the high level of irreversibility or non-isentropic process and viscous effects in the burner. The burner pressure ratio ? =pt5pt4Burner temperature ratio ? b=Tt5Tt4 Since no work is done only heat transfer, the efficiency of the burner is analysed using the heating value NCV of the fuel used. Thus, efficiency ? b=hea t addedHeating value of fuel=ma+mfht5-maht4NCVmf Given that f=mfma, ? b= 1+fht5- ht4NCVf Equivalence Ratio of combustion It is the ratio of the actual fuel to air ratio of the combustion process to the stoichiometric fuel to air ratio. This ratio produces a means of classifying the combustion process to show whether it is a lean, rich or stoichiometric combustion. The mathematical expression for this is as shown below ? =Actual FARStiochiometric FAR 1 Rich combustion process 3. 4. 4. Turbine Turbine can simply be said to be the antonym of a compressor. In response, a turbine extracts molecular kinetic energy from the air and uses it to drive the turbo machineries which results in the pressure and temperature of the air to drop. If truth be told, Flack (2005) asserted that the turbine uses 70% to 80% of the total energy gained by the air in the combustion chamber to drive the turbo machineries while the remaining 20% to 30% is used to generate thrust in the nozzle.Since the geometry of a turbine have favourable pressure gradient unlike the compressor which is adverse, the efficiency of the turbine is usually very high. Since the turbine is the opposite of the compressor, it has exactly the same configuration of rotor and stator but the volume increase across it which induces the pressure drop. One major problem faced when design a turbine is the deterioration of the blades due to high inlet temperature from the combustion chamber. Based on this, (Song et al. 2002) demonstrated that General Electric uses about 16. 8% of the compressor air to cool the turbine blades of GE 7f engine. Turbine Equation Analysis Given that, Turbine efficiency ? T=ActualIdeal=ht6-ht5ht6s-ht5 T=Tt6-Tt5Tt6s-Tt5 Simplifying the equation given that pt6s=pt6 Tt6sTt5=pt6pt5? -1? ?T=pt6pt5 ? T=Tt6Tt5 ?T=? T-1? T? -1? -1 3. 4. 5. Exhaust Nozzle The nozzle is the final component of the jet engine that the air passes through. The main purposes of the nozzle is to add extra acceleration to the h igh velocity exiting air, reduces its total pressure to that of ambient condition and finally generate sufficient thrust. There are two conditions that occur in the exit of the nozzle depending on the ambient pressure. The first condition is termed under-expansion which occurs when the ambient pressure is less than the exit pressure of the gases.The result of this is that the exit velocity will be lower than it normally is and this makes the momentum component of thrust to be lower than ideal. On the other hand, it will create a positive thrust component for the pressure terms. The second case termed as overexpansion which occurs when the ambient pressure is greater than the exit pressure of the gases. Consequentially, the opposite of what happens in the under-expansion condition occurs where the pressure term is lower and the momentum is higher. Nozzle efficiency ? n=ActualIdeal=ht8-h9ht8-h9s=Tt8-T9Tt8-T9s for constant specific heat Using the steady state energy equation and balanc ing it out, U9=2ht8-h9 . When specific heat is constant U9=2cpTt8-T9 p9pt8=T9sTt8? -1? T9Tt8=11+? -12M92 p9pt8=11+? -12M92-1+ ? n ? n 3. 4.Thermodynamic Process and Cycle of Twin Spool Mixed Flow Turbofan Engine Before any explanation is done from Figure 2, the blue arrows represent the incoming air into the diffuser and the red represent the air flow into the core of the engine while the black arrow represent the bypass air flow through the fan. Finally, the brown arrow represents the air flow after the bypass air and the core air flow have mixed. Based on the arrangement of the turbofan engine in figure 2, it can be seen that air at ambient condition is sucked into the diffuser where the air velocity is reduced and some of its kinetic energy is used to increase the static pressure to the total pressure. The air exiting the diffuser enters the fan or low pressure compressor where it is compressed. Indeed, the molecules of the air gains kinetic and internal energy by colliding rapid ly with one another and as a result increase the enthalpy and static pressure.Also, in the fan, some of the compressed air is bypassed through a duct to be used for the mixing process later while the rest of the air enters into the high pressure compressor of the engine core. In the high pressure compressor, the air is further compressed where the enthalpy and pressure increases as it is released into the combustion chamber. Also, in the high pressure compressor, some of the air mass flow rate is bled out to be used to cool the turbine blades and for air conditioning in the aircraft. In the combustion chamber, the incoming fuel reacts with the air in an oxidation process at constant pressure where the by-product gases gain molecular kinetic energy thereby increasing the enthalpy.This high temperature gases escapes into the high pressure turbine where it is expanded and the gases lose some of their kinetic molecular energy as it enthalpy and static pressure reduces. In other words, i t can be said that the molecular kinetic energy of the gases is being converted to mechanical work which is used to power the high pressure spool. Consequently, the gases enters into the low pressure turbine where it is further expanded to a lower pressure and enthalpy as their molecular kinetic energy is converted to mechanical work to power the low pressure spool. These gases escaping from the low pressure turbine enters the mixing zone or mixer after it has lost most of its total enthalpy and mixes with the bypassed cold air from the duct to further reduce its enthalpy as that of the cold air increases.In other words, the cold air absorbs some of the heat energy from the hot gases until they both attain equilibrium enthalpy. The mixture of the cold air and hot gases both escape at the same equilibrium enthalpy and pressure through the nozzle where their velocity is increased and the pressure is reduced considerably to that of the ambient condition. Furthermore, the exhausted high velocity gases is used to produced thrust for propulsion according to Newton’s third law of motion (In every action, there is equal and opposite reaction). 2 4. 5 6 4 13 0 HPC DIFFUSER FAN/LPC HPT LPT NOZZLE COMBUSTION CHAMBER 2. 5 3 5 8 16 BYPASS DUCT HP Spool LP Spool MIXING ZONEFigure 2 Layout of a Forward Fan Twin Spool Mixed Flow Turbofan Engine P0 P3 P4. 5 P5 P8 P6 P2. 5 P2 P13 P4 ENTROPY (S)(kJ/kg) TEMPERATURE (K) Figure 3 T-S Diagrams for the Forward Fan Twin Spool Mixed Flow Turbofan Engine Chapter 4 Mathematical and Gas Turb 11 Modelling of the Engine 4. 1. Station Numbering and Assumptions Station numbering is a very crucial step that has to be taken when analysis of any thermodynamic system involving many processes is to be done. Moreover, station numbering contributes immensely to showing how the properties of one process relate to another and how the interaction between these processes derives the functional relationship of the thermodynamic system.Returning to the work in hand, the station numbering system that has been adopted for this work on a JT8D-15A turbofan engine is in accordance with the Aerospace Recommended Practice (ARP) and it is shown in figure 2. Assumptions The following assumption were made based on Mattingly (2002) and Kurzke (2007) in order to perform the modelling as listed below * The air flow through the engine is assumed to be steady and one dimensional * The fan and the low pressure Compressor are driven by the low pressure turbine * The overall engine is assumed to have no bleeds in mass flow or power off-take in turbine. * The nozzle of the engine is choked which means the exit pressure will be greater than the ambient pressure. The air is assumed to act as a half ideal gas where the specific heat and ratio is dependent on temperature only. * The areas of each station of the engine is assumed to be constant 4. 2. Design Point Cycle Analysis of the Turbofan Engine The off-design or performance cycle analysis cann ot be done without the design point cycle being defined. The design point cycle in this analysis is obtained using exactly the same data used in the actual test analysis for a JT8D-15A turbofan engine operating at sea level with maximum take-off thrust as shown in (â€Å"JT8D Typical Temperature and Pressure†) and (â€Å"ICAO†). Some of the input parameters such as the isentropic efficiencies and pressure ratios from the actual test data had to be calculated.Since not all the input parameters were given from the actual test data, some of the parameters like inlet corrected mass flow rate, diffuser pressure ratio and efficiency; mechanical spool efficiency had to be guessed in order to complete the analysis and the data are represented below in Table 1. With all the Input Parameter being specified as shown in table 1, the design point cycle simulation of the JT8D-15A turbofan Engine using the Gas Turb 11 software can then be performed. All the steps taken to model the m ixed flow turbofan engine on Gas Turb 11 is clearly represented in the algorithm shown in figure 3 below. COMPONENT| INPUT PARAMETER| | DIFFUSER| Pressure Ratio (? d)| 1| | Inlet Corrected Mass Flow Rate (mc2)| 138. 618 kg/s| FAN| Pressure Ratio (? fan)| 2. 054| | Isentropic Efficiency (? fan)| 0. 78| | Bypass Ratio (? )| 1. 08| Low Pressure Compressor (LPC)| Pressure Ratio (? LPC)| 4. 7| | Isentropic Efficiency (? LPC)| 0. 88| | Nominal Low Pressure Shaft Speed (NLP)| 8160RPM| High Pressure Compressor (HPC)| Pressure Ratio (? HPC)| 3. 77| | Isentropic Efficiency (? HPC)| 0. 864| | Nominal Low Pressure Shaft Speed (NHP)| 11420RPM| Combustion Chamber (cc)| Pressure Ratio (? CC)| 0. 934| | Isentropic Efficiency (? CC)| 0. 99| | Burner Exit Temperature (TIT)| 1277. 15K| High Pressure Turbine (HPT)| Isentropic Efficiency (? HPT)| 0. 9| | HP Spool Mechanical efficiency (? m)| 1| Low Pressure Turbine (LPT)| Isentropic Efficiency (? LPT)| 0. 91| | LP Spool Mechanical efficiency (? m)| 1| T able 1 Input Parameters for the Design Point Cycle Simulation STARTSpecify all the input data gotten from the actual test data as shown in Table 1 Run the Gasturb 11 software and select mixed flow turbofan from the drag down Tab list. Set the scope to ‘More’, set the Calculation Mode as Design and click ‘Run’ Choose the Units to either Imperial or SI and Select the type of fuel from to drop down list to Kerosene, Natural Gas or Hydrogen Estimate the inlet Corrected mc2 Mass Flow rate to the FAN/LPC Choose ‘Single Cycle’ for ‘Select a Task ‘Option and click ‘Run’ Check if the Thrust, SFC, ? HPT, ? LPT and EPR are within (0-10) % of the actual test Experiment END YES NO Figure 4 Design Point Cycle Simulation Algorithm Using Gas Turb 11 Verification of the Design Point simulation ResultsSince not all the input parameters were specified in the actual test data and some of them had to be guessed, it is without any doubt that errors are bound to generate in the simulation results using the Gas Turb 11 software. In order to ensure that the errors accumulated in the simulation were within range, the major output parameters obtained such as net thrust, fuel flow rate, Engine exit pressure ratio, etc were compared to the actual test data as shown in Table 2 and the error range was calculated to be between 0. 25% to 8. 5% which is within an acceptable range. PARAMETERS| ACTUAL TEST DATA| SIMULATED DATA USING GASTURB 11| Net Thrust| 69307. 74| 69320| Engine Exit Pressure Ratio P8P0| 2. 09| 2. 167|Burner Fuel Flow| 1. 100843| 1. 09781| HPT pressure Ratio (? HPT)| 0. 415| 0. 449| LPT Pressure Ratio (? LPT)| 0. 3294| 0. 3514| HPT temperature Ratio (? HPT)| 0. 8097| 0. 8435| LPT temperature Ratio (? LPT)| 0. 7718| 0. 793| Table 2 Comparison Table for the Actual Test Data and Simulated Data Using GasTurb 11 4. 3. Off-Design Point Cycle Simulation of the Turbofan Engine The off-design or performance cycle simulatio n takes into account the concept of module matching of each component through performance maps. This cycle analysis enables the determination of different operating point of the engine at a given design point of the engine.Considering the work in hand, the design point have been defined and verified for the JT8D-15A turbofan engine operating at sea level with maximum take-off thrust which means that different operating points of the engine can be defined with the concept of off-design module matching of the engine. Indeed, the off-design operating point that was considered for the parametric analysis in this work was 30,000ft at M0 0. 8 for the turbofan engine. The off-design modelling of the JT8D-15A engine for the operating point of 30,000ft at M0 0. 8 based on the reference design point defined earlier is clearly demonstrated as follows. The off-design performance cycle simulation may contain some errors because of the component performance maps that were used for the simulation. 4. 3. 1. Module/Component Matching This process only applies to the off-design performance cycle point of the engine.It can simply be defined as the act of synchronising each component of a jet engine to coexist as a unit in order to derive the overall performance characteristics of the jet engine. Component matching involves the process closely studying the ramifications of the actual jet engine overall performance behaviour on the components major characteristics such as pressure ratio, temperature ratio, efficiency and spool speed. This process introduces the concept of empirically determined component performance maps that establishes the relationship between the thermodynamic properties and the geometry of the jet engine itself. 4. 3. 2. Off-Design Component Modelling Diffuser The diffuser was assumed to be adiabatic and the pressure ratio ? d=1 The Isentropic Efficiency was assumed to be 1 For Sea Level,Pamb=101325pa , Tamb=288. 15K For 30,000ft and M0 0. 8, Tamb=288. 15-0. 0 065? 9144 =288. 15-59. 436 =228. 71K Pamb=101325? Tamb288. 155. 2561 =30. 09kpa Tt1=228. 71? 1+? -12M02 =228. 71? 1+1. 4-12? 0. 82 =258K pt1p0=1+ ? d? -12M02 -1 pt1=30. 09? 1+ 1? 1. 4-120. 821. 41. 4-1 pt1=45. 8674kPa pt1=pt2 Tt1=Tt2 Fan and Low Pressure Compressor The inlet corrected mass flow rate is estimated as 138. 618kg/s , As for the off design simulation using the component performance maps for the altitude of 30000ft and Mach no. 0. 8, the actual spool speeds and inlet mass flow rate are calculated based on the estimated inlet corrected mass flow rate as shown below.Low and High pressure spool mechanical efficiency is assumed to be=1 HP spool Speed=11420RPM, LP spool Speed=8160RPM m2=Pt2PSTD? mc2Tt2TSTD =45. 878101. 325? 138. 618258288. 15 Actual Mass flow rate m2=66. 3323kg/s N=Tt2TSTD? NcLP=228. 71288. 15? 8160=7722 RPM The calculated actual mass flow rate and spool speed were used to evaluation the isentropic efficiency and the pressure ratio of the LPC for that operatin g condition from the compressor performance map. Figure 5 Example of a Compressor Performance Map/Curve The diagram above in figure 4 depicts a typical compressor performance map that was used for the off-design point analysis in this work.It can be seen that the x-axis represents the inlet corrected mass flow rate mc2 into the compressor, the y-axis represents the compressor pressure, the red contour lines represents the isentropic efficiencies and the black curved lines represent the relative corrected spool speed. To add to that, the red dash line that ends the speed lines and efficiency lines represent the surge margin which is also known as the stall line that must be avoided since the flow will become unstable in that region. In this work, the inlet corrected mass flow rate and spool speed were calculated which were interpolated on the performance map to obtain the pressure ratio and the isentropic efficiency.For instance, the yellow dot on the map represents a design point tr aced for a given pressure ratio, High Pressure Compressor The inlet corrected mass flow rate into the HPC mc2. 5=mc21+? mc2. 5=138. 6182. 08=66. 64kgs m2. 5=Pt2. 5PSTD? mc2. 5Tt2. 5TSTD N=Tt2. 5TSTD? NcHP The same equation used for the LPC is used to calculate the actual mass flow rate and spool speed which is used to evaluate the isentropic efficiency and pressure ratio when it is operating at an altitude of 30000ft at M0 =0. 8. Verification of the off-design modelling for 30000ft at Mo 0. 8 In order to verify the simulation result gotten for the operational design point of 30000ft at M0 0. , the actual test data results gotten from Mattingly, Heiser and Pratt (2002) for the same operating condition was compared. Due to the difficulties in obtaining a lot of output parameters for this operating point, the result will be verified with only the net thrust generated and the specific fuel consumption. Indeed, the error accumulated was 1. 71% for the net thrust and 0. 83% for the specif ic fuel consumption. PARAMETERS| ACTUAL TEST DATA| SIMULATED DATA USING GASTURB 11| Net Thrust (lb)| 4920| 4836| Specific Fuel Consumption(lb/lbh)| 0. 779| 0. 7855| Table 3 Comparison Table for the Actual Test Data and Simulated Off-design Data Using GasTurb 11 Chapter 5Methodology, Results and Discussions Given that the design point of the JT8D-15A turbofan engine at sea level has been obtained and verified with the actual test data, the operating point of 30000ft at M0 0. 8 was simulated and obtained which now served as the design point for the analysis in this work. Moreover, the procedure taken to define this design point of 30000ft at M0 0. 8 of the JT8D-15A turbofan engine has been clearly stated earlier which gives the permission to conduct the parametric cycle study of the turbofan engine. The parametric cycle studies were done for three different cases for the operational design point of 30000ft at M0 0. of the JT8D-15A turbofan engine as explained as follows. 1. The first parametric analysis case 1 aim to create an understanding of the effects of varying major design parameters on the performance parameters of the turbofan engine when some of the design choices are kept constant. In other words, the bypass ratio and thermal limit parameter (turbine inlet temperature) were varied when the design choices such as the compressor pressure ratio, fan pressure ratio and isentropic efficiencies were kept constant in order to investigate their effects on the performance parameters such as the net thrust, specific fuel consumption, propulsive efficiency, thermal efficiency, and fuel-air-ratio.Much interest is shown nowadays in using alternative fuels like hydrogen and Natural gas in efforts to reduce the cancer known as pollution and the risk of depletion of energy resources. Based on this, conducting a research that focuses of comparing different fuels consumption rate, their risk of pollution and their contribution to the performance of the engine will be re ally valuable. Based on this, a parametric analysis had to be done on the JT8D-15A turbofan engine using three different fuels which are the design point fuel kerosene, hydrogen and natural gas. Since the original design point of the JT8D-15A turbofan was obtained using kerosene fuel, the design points of using hydrogen and natural gas was obtained using the same design choices as that of kerosene.Now that the design points of the JT8D-15A turbofan engine had been defined when using the three different fuels, it had given a go ahead to perform whatever parametric cycle studies of the turbofan engine using the three fuels. In order to compare the performance characteristics of the turbofan engine when it is using the three different fuels, different approaches had to be devised to compare them effectively on a rational basis which defines the last two parametric analysis cases as follows. 2. The second case of parametric analysis was that the fuel flow rate would be kept constant for the three fuels that would be used as the bypass ratio is varied with design choices remaining the same. 3.The third case of study was to make the energy supply into the combustion chamber of the turbofan engine the sa

Haefren-Baum Case

Name of the business: Haefren Baum GmgH Nature of the business: Haefren Baum is a retailer of high quality home furniture located in Cologne, Germany. They have also added three outlet stores in Rhineland, a nearby suburban area. Marketing Analysis: Haefren retails high quality furniture manufactured by Wiegandt has advertised aggressively in order to build and maintain a strong brand image. Haefren benefited tremendously from the successful marketing provided by Wiegandt. Wiegandt has However, because the nature of the product is high-end and durable, sales are subject to fluctuations of the business cycle.During the economic boom leading up to 1993 Haefren, as well as the industry in general, enjoyed strong sales. However, the economic bust in 1993 has slowed sales growth. Decreased consumer confidence caused industry sales growth to decrease from 42. 9% in 1992 to 9% in 1993. Haefren experienced negative sales growth during this period. Haefren has a strong competitive position; h owever, it is quickly deteriorating. The addition of 3 outlets give Haefren an opportunity to capture a wider market than it currently has. However, new competitors entering the market are all competing for stagnant demand.European retailers are also entering the German furniture market which makes it even harder for Haefren to maintain its competitive advantage. Operations Analysis: Haefren obtains its merchandise directly from the manufacturer, Weigandt. Weigandt has provided â€Å"fairly liberal† credit terms which include a discount for early payment (2% 10, net 30). However, they have jeopardized their lose credit terms because of inefficiencies with their receivables, inventories, and fixed assets. A major issue that Haefren needs to address is the delinquency of their customers accounts.From 1993 to 1995, days sales outstanding have increased to 77 days, which is dramatically higher than the 30-day monthly installment terms. This delay in collection is creating cash fl ow problems for Haefren. It is causing them to fall behind on their payments to Weigandt and miss out on significant savings from the early payment discount. The increase in its collection period was expected in 1993 due to the worsening economy. However, the economy is now improving and Haefren’s collection period is still increasing. This signals to inefficiencies within the company’s collection department.Perhaps, they should even consider increasing the down payment required to establish credit. The sluggish sales in the furniture industry can account for the increase in inventory days. Haefren inventory in 1994-1995 stayed on the floor for around 129 days before it was sold. The longer period that they are holding inventory is increasing their cost of goods sold. Not only are they holding inventory for a longer period of time, but they are also underutilizing their fixed assets. Fixed asset turnover decreased for Haefren from 1993-1994. They constructed three new outlet stores which should have helped them with sales.However, due to the sluggish demand, these new fixed assets are not returning the sales they were supposed to. Haefren needs to consider whether these outlets are worth the investments. They could potentially benefit from sending inventory from their retail store to the outlet sooner. Even if they have to sell it at a discount, if they do not lose money on it, the lower revenue would be more beneficial. It appears that Haefren might be experiencing problems with human resources as well. They carry a debt account for notes payables for employees.This account reflects loans that have been made from the employees, or their relatives, to the company. Why are they borrowing from employees? This could potentially come from accrued wages, which would be an even greater issue. Financial Analysis: Haefren’s funding has come from bank loans and utilizing credit from its vendors. Funding needs increased due to the addition of 3 new outlet stores. These outlet stores have increased Haefren’s debt over the three years in questions. Along with this new debt, two of the original partners sold their shares to the other two partners.It seems like there are too many changes going on at Haefren all at once. In regards to cash flows, Haefren is performing poorly. Cash flows from operations are unhealthy and the total cash on hand has declined over the three years in question. Total cash flow from operations is positive, however, they appear to be driven by depreciation. Their negative net income (net loss), is not driving operations cash flow in a positive direction. They are also carrying a great deal of inventory which is consuming their cash. In order for them to drive up net income they need to find a way to decrease their inventories.Accounts receivables are also impacting cash flows in a negative way. A/R have increased each year, which can be attributed to the weak economy. This drag in A/R is causing the m to receive cash-in after cash goes out. Their cash flow problems are evident when analyzing their account payable days. Wiegdant has given them competitive terms (2% 10, net 30), however, Haefren cannot meet those terms. Their account payable days have increased to 66 days. It is taking them twice as long to repay their current liabilities. All of these cash flow problems are having a negative impact on their liquidity.Their quick ratio is increasing from year to year, but it is being driven by inventories. Their Current ratio also appears to be ok; however, it is being driven by accounts receivables. Although they appear to going in the right direction, it is not a good sign for Haefren. Inventories and receivables are also driving down operating margin. The positive cash flow from investments reflects the addition of the three new outlets. Investing in long term assets is a good thing. Ideally, the addition of these assets (outlets) should have led to higher revenues for Haefren . However, they invested in those assets at the wrong time.Their sales growth (revenues) cannot support the addition of the outlets. Weak sales led to a negative return on equity and the addition of the three outlets led to a negative net profit margin. The interest being paid on the current debt in 1995 was 3. 08% of their net sales. Haefren cannot handle any more debt without first making significant changes to their operations. Summary: A weak economy has led to Haefren poor financial conditions. They expanded at the wrong time, right when the economy went sour. They also need to handle their inventories and accounts receivable in order to avoid further cash flow problems.

Clara Barton essays

Clara Barton essays Clarissa Harlowe Barton was her name, a smart, and intelligent women. Clara is what people called her. Sarah Barton gave birth to Clara on December 25, 1821 in a small hospital in North Oxford, Massachusetts. Her parents, Stephen and Sarah, thought she was a special baby because she was born on Christmas Day. Clara was the fifth child born in her family. When Clara was three her parents thought it would be a good idea for her to start schooling. Her teachers all adored her and thought she was a dedicated student and very promising. One day when Clara was eleven years old and listening to another one of her fathers stories in the living room, she learned a lot about military, battle strategies, and first aid tips. When her brother David fell from barn rafters Clara of course left school to go aid him. At the age of thirteen Clara was really interested in aiding the poor, and tutoring children. She only got better at nursing while on the job, since there was no such thing as a Nursing school. At the age of six-teen, and not knowing what she was doing, Dr. Lorenzo Fowler, a Phrenologist, told her parents it would be best for Clara if she would start teaching instead. So she started teaching in a small town school. Through out teaching in the school, Clara thought the children could use some better school supplies. She brought this to the town meeting and within a year, she was granted her request. Clara was so thrilled with this, but she thought there might be something else out there for her, her family, her future. In 1845, Clara started her own school for the mill workers; it was a free public school. She even had a building built for her, but she was denied to fulfill the position of Principal of that school because she was a woman. She late found out that they hired a male, she was so upset she left the school. By the time Clara turned twenty-five, she was unemployed. Her brother David then becam...

History of the Welfare State in the United Kingdom essays

History of the Welfare State in the United Kingdom essays The UK's welfare system has a long history and has evolved as a response to social, economic and political changes in society. The birth of the welfare state after WWII was a watershed in British history. The newly elected Labor Government "took on the task of setting up a 'welfare state' that would systematically tackle Beveridge's 'five giants'. The creation of a new, more equal society was the key task of government. Social policy was at the top of the political agenda". (Walsh et al, p.46). Elaborating more on the welfare state as far as Beveridge's report is concerned, William Beveridge's report according to Chandler (2002), was to help the citizens of Britain to combat the five giant evils; squalor, ignorance, want, idleness and disease. He goes on to explain that the report was very vital in the sense that Britain was then at war and filth, poverty, illiteracy, unemployment and diseases were common due to the daily bombardment of Britain that crippled and even destroyed most industries, people's homes etc. Before the report, Beveridge was in the liberal reforms from 1906 to 1914 which benefited just few people in Britain hence the gap between the poor and the rich became very huge and inequality became part of the British society. Furthermore, according to Harling (2001), the reforms after Beveridge's report did not take into account wage earners families in other words; this reform did not benefit people in employment regardless of their income. These wage earners did not get any entitlement for medical treatment, because of this, most care takers especially mothers put off any medical treatment for themselves in order to afford treatment for their children which was very disturbing because most people lost their lives because of this unequal system of health care in Britain (Harling 2001). Nevertheless, Chandler (2001) explains that, the Rowntree report conducted in 1936 showed that want or poverty was still a big pro...

Biography of Moses, Leader of the Abrahamic Religions

Biography of Moses, Leader of the Abrahamic Religions Moses, if he existed, likely lived in Egypt during the dynastic New Kingdom, and he was an early leader of the Hebrews and one of the most important figures in Judaism. He is a significant patriarch of all the Abrahamic religions, those who use the Torah, Christian Old Testament, or Quran as sacred texts. Fast Facts: Moses Known For: Patriarch of the Torah, Christian Old Testament, and QuranBorn: Land of Goshen, New Kingdom, EgyptParents: Yocheved and AmramDied: Mount Nebo, MoabSpouse(s): Adoniah or Tharbis, an Ethiopian princess; Tzipporah the MidianiteChildren: From Tzipporah, Gershom and Eliezer. Early Life If there was a historical man named Moses, he would most likely have been born in Egypt (the Land of Goshen) during the reign of Ramses II (ruled 1279–1213 BCE), the pharaoh of the New Kingdoms 19th dynasty. According to the Torah, Moses was the youngest of three children born to Yocheved (sometimes spelled Jochebed) and Avram. Yocheved was the daughter of Levi; she married Avram, a grandson of Levi, which means Yocheved was also Avrams aunt. Moses siblings were Aaron (the founder of the Hebraic priestly dynasty) and Miriam (an important prophetess). Pharaohs Curse Not much else is available on Avram or Yocheved in the Torah itself, but Midrashim records- ancient rabbinical commentaries on the Torah- say that Yocheved was 130 years old when Moses was born and that Avram divorced Yocheved while she was pregnant, so that their son Moses would escape the pharaohs decree. According to Exodus, the pharaoh of Egypt decreed that all Hebrew boy babies were to be drowned at birth. Yocheved hid her newborn son for 3 months and then placed her baby in a wicker basket in the Nile River reeds. The baby cried and was rescued by one of the pharaohs daughters, who kept the baby. This legend is similar to one in the Mesopotamian story of Gilgamesh, when the Sumerian king Sargon I was placed in a reed basket and floated down the Euphrates river. In the Court of the Pharaoh Moses sister, the prophetess Miriam, knew what would occur and was watching when the daughter of the pharaoh took the baby. Miriam came forward to ask the princess if she would like a Hebrew wet nurse for the infant. When the princess agreed, Miriam fetched Yocheved. Moses grew up in the palace as an adopted son of the pharaohs daughter (identified the Midrash as Queen Bithia), but he went to see his own people when he grew up, and as an adult he may have been a governor working for Ramses II. During Ramses IIs reign, Ethiopia was an Egyptian province with an Egyptian governor named Mesui, who some scholars suggest was Moses. While in Ethiopia, Moses married an Ethiopian princess named Tharbis or Adonais. When he witnessed an overseer beating a Hebrew, Moses struck the Egyptian and killed him, with the beaten Hebrew as a witness. The pharaoh learned that Moses was the murderer and ordered his execution. Moses fled to the land of Midian, where he married Tzipporah, daughter of Jethro. Their sons were Gershom and Eliezer. A Burning Bush In the land of Midian, Moses was tending a flock of sheep for his father-in-law when he saw a bush that was burning but not being consumed by the flames. He approached the bush and first an angel and then God (or more properly Yahweh) himself spoke to him, telling him that he must return to Egypt and shepherd the Israelites out to Canaan, their promised land of milk and honey. Moses was convinced when Yahweh changed his staff to a snake, then gave him a new staff with which to lead his people. Moses returned to Egypt to seek the release of the Hebrews and to bring them to Canaan, but when he approached the pharaoh, Ramses refused to release the Hebrews. In retaliation, Yahweh imposed a series of 10 plagues, the last being the killing the firstborn of every Egyptian. Only after suffering through the beginning of the tenth plague did the pharaoh relent, telling Moses he could take the Hebrews out of Egypt. However, after Moses and the Hebrews left, the pharaoh reversed his decision and had his men follow them. When they reached the Red Sea, Moses used his staff to part the waters and allow the Israelites to pass through the seabed. The Egyptian soldiers also entered the dry seabed, but once the Israelites had safely crossed Moses lifted his arms: the sea closed, and the Egyptian army was drowned. The Biblical Exodus During the 40-year journey of the Hebrews from Egypt to Canaan, Moses went to Mount Sinai to fast and commune with Yahweh for 40 days. There, he received the 10 Commandments from Yahweh. While Moses was gone, his followers including Aaron became nervous that he would not return and built a golden calf. Moses told Yahweh that his followers had begun to leave and Yahweh wanted to kill them, but Moses dissuaded him. But, when Moses saw the actual calf and altar he was so angry he hurled and shattered the two tablets holding the 10 Commandments; Moses made two more tablets and Yahweh inscribed them again. When the people complained they needed food in the desert, Yahweh fed the Israelites with manna, a substance white like coriander seed and tasted like wafers made with honey that rained down from the heavens, and quail. Death Near the end of the 40 years, Yahweh informed Moses that only the new generation of Israelites would enter Canaan, and for that reason, Moses would never see the Promised Land. Moses climbed Mt. Abarim and saw Canaan on the horizon, but that was as close as he would come. Moses chose Joshua as the successor, and, at the ripe old age of 120, Moses climbed Mt. Nebo and died. Who was Moses? Much of this tale is legendary and full of miracles, the stuff of ancient religion. But the role of Moses in the Bible, to Jews, Christians, and Moslems, is rich and complex beyond the miracles. He is seen by all three as the leader of the Israelite people who shepherded them out of Egypt. He is the embodiment of Mosaic law- the one who interceded with Yahweh on behalf of his people, and the one who acted as a judge on behalf of the sacred. He was a teacher and the founder of the cult and sanctuary of the ancient Hebraic religion. The last four books of the Torah- Exodus, Leviticus, Numbers, and Deuteronomy- are primarily dedicated to the life and activities of Moses and his people. Exodus starts with the birth of Moses and Deuteronomy ends with his death and burial by Yahweh. Early interpretations of that circumstance suggested that Moses himself wrote the books of the Torah (or received them direct from Yahweh). Modern biblical scholars mostly agree that the five books were redacted from four independently written documents written long after Moses would have died. The Ptolemaic-era Egyptian historian Manetho mentions Moses- again, long after Mosess death. There are other late historical references in the writings of the Roman historians Josephus, Philo, Apion, Strabo, Tacitus, and Porphyry. His story is told in the Bible in the book of Exodus and the ancient commentaries on the biblical text known as the midrashim. As Musa, he is also is a significant prophet in the Quran. Biblical scholar J. Van Seters, said it best, The quest for the historical Moses is a futile exercise. He now belongs only to legend. Sources Feldman, Louis H. Josephus Portrait of Moses. The Jewish Quarterly Review 82.3/4 (1992): 285–328.Josephus Portrait of Moses: Part Two. The Jewish Quarterly Review 83.1/2 (1992): 7–50.Nigosian, S. A. Moses as They Saw Him. Vetus Testamentum 43.3 (1993): 339–50.Robinson, Marilynne. Moses. Salmagundi 121/122 (1999): 23-46.RÃ ¶mer, Thomas. Moses Outside the Torah and the Construction of a Diaspora Identity. The Journal of Hebrew Scriptures 8.15 (2008): 1–12.Van Seters, John. Moses. The Encyclopedia of Religion. Ed. Eliade, Mircea. New York: Macmillan, 1987. 116.Wineman, Aryeh. Between Person and Metaphor: Moses in the Hasidic Homily-Literature. Hebrew Studies 59 (2018): 209–20.

The Artwork Soft Calendar for the Month of August, 1962. Metropolitan Assignment

The Artwork Soft Calendar for the Month of August, 1962. Metropolitan Museum of Art in New York City - Assignment Example One must wonder why the artist uses the particular medium that he does—especially since it is quite strange. â€Å"Soft Calendar for the Month of August, 1962† is basically canvas filled with shredded foam rubber; it’s painted with Liquitex and enamel. Now, Liquitex, as one understands it, is primarily a plastic paint—which we now know as acrylic gesso. Gesso is what artists usually put on their canvases in order to prime the piece of artwork with paint. So, it seems rational that Claes used Liquitex, perhaps for a first coat. Then, he most likely next applied enamel, which leaves a decorative and glassy coating. It’s a type of paint used for modeling (such as miniature toy plane replicas, etc.). One must ask why the artist uses this particular medium besides why he actually uses the types of paints—and rather, why does he feel this is the best way to represent his art? Perhaps this was the easiest way to paint shredded foam rubber. It must h ave taken some masterful skill to form the rubber just the way he wanted it, because the rubber numbers on the calendar look like dough. The advantages of working with acrylic gesso would be that the first coat would dry easily. The limitations of working with enamel include the fact that enamel takes a longer time to dry. III. Style Elements of the composition work to constitute the artist’s style, much in the way that putting a bunch of puzzle pieces together creates a whole picture. As for what movement within which Oldenburg was working, he was clearly in the realm of various possible categorizations: Modernist, Abstract Expressionism, and Pop Art. It’s possible it might have even been more than one style blended together. At any rate, â€Å"Claes Oldenburg's highly individual figurations make him one of the leading protagonists of Pop Art† (Osterwold 193). Pop art, short for popular art, was at its heyday in the ‘60s, along with the likes of Roy Licht enstein and others. Unmistakably, as one can see below, the calendar for the month of August of 1962 starts with the number â€Å"29,† as that was the day of the week from the previous month of July in that particular year. One also may note that the August calendar of 1962 ends with the number â€Å"1,† because the last day in the calendar was September 1st of 1962—according to the painting. The numbers and letters almost look like baked bread dough rising. More is forthcoming about why this painting looks like it does, in the next section regarding the context of the painting. IV. Context One should examine also, the context of the work. This was painted in the 60s by Claes Oldenburg. He was born in Sweden in 1929, but is an American citizen. It’s uncertain exactly where he painted it, nor with what other works it would be in conversation with unless one talks about this painting being a type of conversation piece in the context of Pop Art. All of the f irst days of the week on the calendar are painted red, while the other days are white. One is unsure whether the colors or this particular month held any kind of cultural or historical events or issues which the piece is addressing. To be sure, Soft Calendar for the Month of August, 1962 is definitely riveting. It makes you ask why a thousand times. Why are the first days of the week painted red, and the rest white? Why do these numbers look like rising bread dough? And so forth and so on. It is a discussion that must be had. V. Conclusion

What The Course Offers Essay Example | Topics and Well Written Essays - 250 words

What The Course Offers - Essay Example A student is first enrolled in kindergarten, the primary, secondary and finally university. In all the stages of education, a student is taught different things from various subjects. The course shows the importance of these learning activities to the growth of the whole person. As the child’s brain develops, the involvedness of learning activities also increases. It is necessary for students to undergo the various stages of learning for them to identify the truth. The university education is crucial for students as it helps them know the truth by conducting research. The course helps students to recognize the importance of research as far as the truth is concerned; it contributes to unraveling the secret behind some issues. The course sensitizes the importance of continuous learning as it helps students know the things they could not have learned. In conclusion, the course opens the mind of learners concerning the significance of learning. Learning is a continuous process, and it assists students in mental, psychological and physical development. The course offers much information regarding how to learn.

The Negligence In Term Of Law Essay Example | Topics and Well Written Essays - 1500 words

The Negligence In Term Of Law - Essay Example The above definition has been taken from the case of Ryland. According to the Civil Act 2002 Section 42, the first part of negligence is the duty of care:â€Å"the standard of care required of the defendant is that of a reasonable person in the defendant’s position who was in possession of all the information that the defendant either had or ought reasonably to have had, at the time of the incident out of which the harm arose†   After ascertaining that there was a duty of care, the plaintiff has to prove that there was a breach of such duty, which resulted in an injury to the Plaintiff. In order to establish negligence as a Cause of Action under the law of torts, a plaintiff must prove that the defendant had a duty to the plaintiff, the defendant breached that duty by failing to conform to the required standard of conduct, the defendant's negligent conduct was the cause of the harm to the plaintiff, and the plaintiff was, in fact, harmed or damaged.The defense of Marv in would be the appropriate precaution of risk, and before concluding that argument let us define and precaution of risk as covered in the Act:â€Å"A person is not negligent in failing to take precautions against a risk of harm unless— (a) The risk was foreseeable (that is, it is a risk of which the person knew or ought to have known); and (b) the risk was not insignificant; and (c) in the circumstances, a reasonable person in the person’s position would have taken those precautions.†... The defence of Marvin would be appropriate precaution of risk, and before concluding that argument let us define and precaution of risk as covered in the Act: â€Å"A person is not negligent in failing to take precautions against a risk of harm unless— (a) the risk was foreseeable (that is, it is a risk of which the person knew or ought to have known); and (b) the risk was not insignificant; and (c) in the circumstances, a reasonable person in the person’s position would have taken those precautions.†4 Marvin has the defence of saying that he took enough precaution against the risk, but the pothole was in such a place that any other person in a similar situation would not have been able to avoid the accident. Along with this fact, the bike did not get damaged and Norton faced injury due to the fact that he had already been injured at the spot where he fell, which resulted in the aggravation of such injury. The right of Marvin is to sue the University of Canberra under the common law principle for not taking enough precaution in order to avoid the pothole where the bike crashed. He can transfer the liability onto the college by arguing on the basis of negligence on the part of college through not maintaining the University campus in the right order. The liability of Marvin is the fact that his actions caused injury to Norton, and on top of that he was drunk while he was riding. He did not take enough care and precaution when he knew while being drunk he should not have ridden the bike. Moving onto Norton, let us first deal with his liability. Norton was the one who introduced Marvin for drinking to drown his sorrows. From this point it can be inferred that he was totally aware of what was

Pantheon Essay Example | Topics and Well Written Essays - 1500 words

Pantheon - Essay Example It was thought that this inscription referred to the present temple, but Agrippa's temple was destroyed and then restored several times by Domitian and Trajan. It was fully reconstructed by Hadrian around 125 A.D., but he preserved Agrippa's inscription. This new Pantheon has been attributed to the architect Apollodorus of Damascus, one of the most famous architects of the Ancient world. The Greek influences we can appreciate in the portico (very similar to the pronaos of the Greek temples) are due to the great admiration Hadrian felt for Greek culture. After the portico, we find a big circular cella or rotunda, covered with a semispherical dome with an oculus opened to the sky. The portico and the rotunda are linked by a polygonal structure. The dome rests on a cylindrical drum and it is decorated with coffers, which were designed to reduce the weight of the dome; it is the world's largest concrete dome. The walls of the temple have the same height as the radius of the dome and the total height is equal to the diameter, so a perfect imaginary sphere can be inscribed in the interior of the Pantheon. The structure of the Pantheon is very different from the conventional structure of the roman temples, which was very influenced by the preceding Etruscan and Greek models, so when it was built it represented an important innovation. Although we can find examples of domes resting in a cylindrical drum in some previous buildings, like the thermal baths of Agrippa or Caracalla, the dome of the Pantheon is the first one built with such big dimensions. The materials used in the Pantheon were also very innovative; the concrete applied to the construction of the dome and the marble, used in the floor, which was a symbol of magnificence and splendor. Agrippa's temple was smaller than the present temple and it was facing to the south (the actual Pantheon is facing to the north). It seems that the structure was very similar to the actual temple, and it was based in the architectural principles of Vitruvius. In the pronaos, now decorated with Corinthian columns, were erected the statues of Augusto and Agrippa as the promoters of the temple, so what people saw at first sight were the figures of the Emperors, as the developers of this magnificent architectural work. The geometry of the Pantheon has a deep symbolic meaning. According to the plane geometry and Vitruvius' ideas, the squared Greek portico represents the Earth and the circular rotunda the Heaven. The rotunda and the dome are linked by an octagon, by which the squaring of the circle is achieved; this will mean the indestructible union between matter and spirit. In the floor we can also find geometrical drawings of circles inscribed inside squares. Furthermore, the lower part of the drum's wall is drilled with niches, suggesting a continuity in the unlimited space. The columns that support these niches have been constructed as if they were not supporting the dome, so it seems to be floating in the air. The dome represents the vault of heaven and each of the five levels of coffers represents the five concentric spheres of the Ancient planetary system. The central oculus, which illuminates the interior of the temple, symbolizes the