In company that designs road cars and heavy trucks, it important to make the proper selection of the engines. Your part as a system energy engineer is to make a proper selection between an engine operates on Otto cycle/gasoline engine or Diesel cycle/diesel engine. Your head of department asked you to provide a detailed technical report that shows your selection for engine to be used with heavy truck vehicle. This is best achieved by performing the following tasks: Section.1: 1. Which engine does operate at lower rpm and has higher air-fuel mass ratio? 2. Which engine does burn fuel more completely? 3. Which engine has lower fuel cost? 4. Explain what compression ratio for Otto and Diesel cycles means 5. Explain what cut-off ratio for Diesel cycles means 1:06 pm 6. Explain the limitations of SI engines in terms of their ability to operate at much higher compression ratios. What is this limitation called? 7. Provide general plot(s) for thermal efficiency, 7 vs compression ratio, r for air with k = 1.4 and show the typical compressions ratios for gasoline and diesel engines. Compare your plots in terms of the typical compression ratio values. 8. Using your plot of the thermal efficiency, n vs compression ratio, r for air with k = 1.4 for a diesel engine, show how will the thermal efficiency, 7 would change with the cut-off ratio values. 9. Explain mathematically how the thermal efficiency, n of Otto cycle is always higher than diesel cycle if-and-only-if both engines are operated at same compression ratio, r. 10. Based on Part.6, 7, indicate which engines has more tendency to work at higher compression ratio values. 11. Based on Part.1, 2, 3, 10, explain why diesel engine would have higher overall efficiency than gasoline engine and explain how this would not violate your results in Part.9. 12. Assume you have Otto cycle operates at compression ratio of 9 and Diesel cycle operates at ratio of 23, which engine will have better overall efficiency? 13. Which engine has heat transfer addition at constant pressure and constant volume, how does this affect the overall efficiency? 14. Compare the compression process of both engines in terms of the working fluid (air-fuel mixture or air only) 15. Compare both engines in terms of the way that the combustion is initiated. Based on what you have explained and explored previously, make your recommendations to select an engine for heavy truck in which the following design requirement must be met: Operates at lower rpms with less fuel consumption. Lower operational cost. Higher overall efficiency. Also, give an example of a well-known design of the engine you have selected, showing its overall efficiency value, number of cylinders, power output, operating rpm, date of manufacturing, estimated total engine cost, country of manufacture and brand, availability of spare parts in local market, warranty period, and supplier name. Section.2: In case you select the diesel engine, evaluate the performance a four-cylinder two stroke 2.4 L diesel engine that operates on ideal Diesel cycle has a compression ratio of 23 and cut off ratio of 1.75. Air is at 75°C and 105 kPa at the beginning of the compression process. This is best achieved by: Determine the required power the engine will deliver at 3500 rpm. In case the diesel engine is four stroke what required power, it will deliver, compare this value with two stroke diesel engines. 1:06 pm Figure 2: Two – stroke diesel engine (Left) Four - stroke diesel engine (Right) B ll 96% É 5:03 Hijjawi 7 photos Student Name/ID Number/Section 10101173: Fundamentals of Thermodynamics and Heat Engines HTU Course Number and Title Assignment Brief and Guidance Part 1: Take-home, In-lab and viva activity related to topics covered in LO3 &LO4. You work as an energy engineer in a company that provides design services for different types of energy and power systems. Your manager assigned you to work on specific tasks for different running projects. Project 1: Reciprocating/internal combustion engines are widely used as a portable electrical generator in many commercial and industrial applications. You are required to describe the operation sequence of different types of available engines and explain their mechanical efficiency. Figure 1: A four-cylinder four-stroke engine You have been asked to deliver a detailed technical report and show your approach in solving and discussing the following: 1. By constructing simple sketch, show the properties and characteristics of reciprocating/internal combustion engine of both spark ignition (SI) and compression ignition (CI). You must indicate the following, in case they are existed: 1:05 pm Piston-cylinder parts, Top dead centre TDC, Bottom dead centre BDC, and Clarence volume. a. b. Intake vale, Exhaust Valve, Spark plug, Stroke displacement, Bore dimeter. c. Show the complete cycle of ideal Otto and Diesel cycles by means of P-V and T-S diagrams, showing on them the input and output heat and net output work, process type (isentropic, isobaric or isothermal). 2. Describe the operational sequence of four stroke spark ignition (SI) and four stroke compression ignition (CI) engines, plot the P-V and T-S diagrams for each process during the cycle with the aid of sketches to show the mechanical operation of the piston-cylinder at each process as follows: a. The thermodynamics cycle must indicate the input and output heat and net output work, process type (isentropic, isobaric or isothermal). b. The piston-cylinder mechanical sketches must indicate the input and output heat. c. The piston-cylinder mechanical sketches must indicate the movement of piston (upward/downward). d. The piston-cylinder mechanical sketches must indicate the expansion and compression. e. The piston-cylinder mechanical sketches must indicate the air-fuel mixture intake and exhaust gasses. f. The piston-cylinder mechanical sketches must indicate when the spark plug is in its active mode. 3. What parameter would you use to measure the mechanical efficiency of two and four stroke engines and what parameter would you fix to compare between both types. Show your explanatic appropriate relation, compare the mechanical efficiency of both two and four stroke engines in terms of their power-to-weight and power-to-volume ratios and provide a list showing the advantages and disadvantages of four-stroke (4S) and two stroke (2S) engines. using the
In company that designs road cars and heavy trucks, it important to make the proper selection of the engines. Your part as a system energy engineer is to make a proper selection between an engine operates on Otto cycle/gasoline engine or Diesel cycle/diesel engine. Your head of department asked you to provide a detailed technical report that shows your selection for engine to be used with heavy truck vehicle. This is best achieved by performing the following tasks: Section.1: 1. Which engine does operate at lower rpm and has higher air-fuel mass ratio? 2. Which engine does burn fuel more completely? 3. Which engine has lower fuel cost? 4. Explain what compression ratio for Otto and Diesel cycles means 5. Explain what cut-off ratio for Diesel cycles means 1:06 pm 6. Explain the limitations of SI engines in terms of their ability to operate at much higher compression ratios. What is this limitation called? 7. Provide general plot(s) for thermal efficiency, 7 vs compression ratio, r for air with k = 1.4 and show the typical compressions ratios for gasoline and diesel engines. Compare your plots in terms of the typical compression ratio values. 8. Using your plot of the thermal efficiency, n vs compression ratio, r for air with k = 1.4 for a diesel engine, show how will the thermal efficiency, 7 would change with the cut-off ratio values. 9. Explain mathematically how the thermal efficiency, n of Otto cycle is always higher than diesel cycle if-and-only-if both engines are operated at same compression ratio, r. 10. Based on Part.6, 7, indicate which engines has more tendency to work at higher compression ratio values. 11. Based on Part.1, 2, 3, 10, explain why diesel engine would have higher overall efficiency than gasoline engine and explain how this would not violate your results in Part.9. 12. Assume you have Otto cycle operates at compression ratio of 9 and Diesel cycle operates at ratio of 23, which engine will have better overall efficiency? 13. Which engine has heat transfer addition at constant pressure and constant volume, how does this affect the overall efficiency? 14. Compare the compression process of both engines in terms of the working fluid (air-fuel mixture or air only) 15. Compare both engines in terms of the way that the combustion is initiated. Based on what you have explained and explored previously, make your recommendations to select an engine for heavy truck in which the following design requirement must be met: Operates at lower rpms with less fuel consumption. Lower operational cost. Higher overall efficiency. Also, give an example of a well-known design of the engine you have selected, showing its overall efficiency value, number of cylinders, power output, operating rpm, date of manufacturing, estimated total engine cost, country of manufacture and brand, availability of spare parts in local market, warranty period, and supplier name. Section.2: In case you select the diesel engine, evaluate the performance a four-cylinder two stroke 2.4 L diesel engine that operates on ideal Diesel cycle has a compression ratio of 23 and cut off ratio of 1.75. Air is at 75°C and 105 kPa at the beginning of the compression process. This is best achieved by: Determine the required power the engine will deliver at 3500 rpm. In case the diesel engine is four stroke what required power, it will deliver, compare this value with two stroke diesel engines. 1:06 pm Figure 2: Two – stroke diesel engine (Left) Four - stroke diesel engine (Right) B ll 96% É 5:03 Hijjawi 7 photos Student Name/ID Number/Section 10101173: Fundamentals of Thermodynamics and Heat Engines HTU Course Number and Title Assignment Brief and Guidance Part 1: Take-home, In-lab and viva activity related to topics covered in LO3 &LO4. You work as an energy engineer in a company that provides design services for different types of energy and power systems. Your manager assigned you to work on specific tasks for different running projects. Project 1: Reciprocating/internal combustion engines are widely used as a portable electrical generator in many commercial and industrial applications. You are required to describe the operation sequence of different types of available engines and explain their mechanical efficiency. Figure 1: A four-cylinder four-stroke engine You have been asked to deliver a detailed technical report and show your approach in solving and discussing the following: 1. By constructing simple sketch, show the properties and characteristics of reciprocating/internal combustion engine of both spark ignition (SI) and compression ignition (CI). You must indicate the following, in case they are existed: 1:05 pm Piston-cylinder parts, Top dead centre TDC, Bottom dead centre BDC, and Clarence volume. a. b. Intake vale, Exhaust Valve, Spark plug, Stroke displacement, Bore dimeter. c. Show the complete cycle of ideal Otto and Diesel cycles by means of P-V and T-S diagrams, showing on them the input and output heat and net output work, process type (isentropic, isobaric or isothermal). 2. Describe the operational sequence of four stroke spark ignition (SI) and four stroke compression ignition (CI) engines, plot the P-V and T-S diagrams for each process during the cycle with the aid of sketches to show the mechanical operation of the piston-cylinder at each process as follows: a. The thermodynamics cycle must indicate the input and output heat and net output work, process type (isentropic, isobaric or isothermal). b. The piston-cylinder mechanical sketches must indicate the input and output heat. c. The piston-cylinder mechanical sketches must indicate the movement of piston (upward/downward). d. The piston-cylinder mechanical sketches must indicate the expansion and compression. e. The piston-cylinder mechanical sketches must indicate the air-fuel mixture intake and exhaust gasses. f. The piston-cylinder mechanical sketches must indicate when the spark plug is in its active mode. 3. What parameter would you use to measure the mechanical efficiency of two and four stroke engines and what parameter would you fix to compare between both types. Show your explanatic appropriate relation, compare the mechanical efficiency of both two and four stroke engines in terms of their power-to-weight and power-to-volume ratios and provide a list showing the advantages and disadvantages of four-stroke (4S) and two stroke (2S) engines. using the
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Kreith, Frank; Manglik, Raj M.
Chapter1: Basic Modes Of Heat Transfer
Section: Chapter Questions
Problem 1.3DP
Related questions
Question
Transcribed Image Text:In company that designs road cars and heavy trucks, it important to make the proper selection of the engines.
Your part as a system energy engineer is to make a proper selection between an engine operates on Otto
cycle/gasoline engine or Diesel cycle/diesel engine. Your head of department asked you to provide a detailed
technical report that shows your selection for engine to be used with heavy truck vehicle. This is best
achieved by performing the following tasks:
Section.1:
1. Which engine does operate at lower rpm and has higher air-fuel mass ratio?
2. Which engine does burn fuel more completely?
3. Which engine has lower fuel cost?
4. Explain what compression ratio for Otto and Diesel cycles means
5. Explain what cut-off ratio for Diesel cycles means
1:06 pm
6. Explain the limitations of SI engines in terms of their ability to operate at much higher compression
ratios. What is this limitation called?
7. Provide general plot(s) for thermal efficiency, 7 vs compression ratio, r for air with k = 1.4 and show
the typical compressions ratios for gasoline and diesel engines. Compare your plots in terms of the typical
compression ratio values.
8. Using your plot of the thermal efficiency, n vs compression ratio, r for air with k = 1.4 for a diesel
engine, show how will the thermal efficiency, 7 would change with the cut-off ratio values.
9. Explain mathematically how the thermal efficiency, n of Otto cycle is always higher than diesel cycle
if-and-only-if both engines are operated at same compression ratio, r.
10. Based on Part.6, 7, indicate which engines has more tendency to work at higher compression ratio
values.
11. Based on Part.1, 2, 3, 10, explain why diesel engine would have higher overall efficiency than gasoline
engine and explain how this would not violate your results in Part.9.
12. Assume you have Otto cycle operates at compression ratio of 9 and Diesel cycle operates at ratio of 23,
which engine will have better overall efficiency?
13. Which engine has heat transfer addition at constant pressure and constant volume, how does this affect
the overall efficiency?
14. Compare the compression process of both engines in terms of the working fluid (air-fuel mixture or air
only)
15. Compare both engines in terms of the way that the combustion is initiated.
Based on what you have explained and explored previously, make your recommendations to select an engine for
heavy truck in which the following design requirement must be met:
Operates at lower rpms with less fuel consumption.
Lower operational cost.
Higher overall efficiency.
Also, give an example of a well-known design of the engine you have selected, showing its overall efficiency
value, number of cylinders, power output, operating rpm, date of manufacturing, estimated total engine cost,
country of manufacture and brand, availability of spare parts in local market, warranty period, and supplier name.
Section.2:
In case you select the diesel engine, evaluate the performance a four-cylinder two stroke 2.4 L diesel engine
that operates on ideal Diesel cycle has a compression ratio of 23 and cut off ratio of 1.75. Air is at 75°C and 105
kPa at the beginning of the compression process. This is best achieved by:
Determine the required power the engine will deliver at 3500 rpm.
In case the diesel engine is four stroke what required power, it will deliver, compare this value
with two stroke diesel engines.
1:06 pm
Figure 2: Two – stroke diesel engine (Left) Four - stroke diesel engine (Right)
Transcribed Image Text:B ll 96% É
5:03
Hijjawi
7 photos
Student Name/ID
Number/Section
10101173: Fundamentals of Thermodynamics and Heat Engines
HTU Course Number and Title
Assignment Brief and Guidance
Part 1: Take-home, In-lab and viva activity related to topics covered in LO3 &LO4.
You work as an energy engineer in a company that provides design services for different types of
energy and power systems. Your manager assigned you to work on specific tasks for different
running projects.
Project 1:
Reciprocating/internal combustion engines are widely used as a portable electrical generator in many
commercial and industrial applications. You are required to describe the operation sequence of different
types of available engines and explain their mechanical efficiency.
Figure 1: A four-cylinder four-stroke engine
You have been asked to deliver a detailed technical report and show your approach in solving and
discussing the following:
1. By constructing simple sketch, show the properties and characteristics of reciprocating/internal
combustion engine of both spark ignition (SI) and compression ignition (CI). You must indicate
the following, in case they are existed:
1:05 pm
Piston-cylinder parts, Top dead centre TDC, Bottom dead centre BDC, and Clarence
volume.
a.
b. Intake vale, Exhaust Valve, Spark plug, Stroke displacement, Bore dimeter.
c. Show the complete cycle of ideal Otto and Diesel cycles by means of P-V and T-S diagrams,
showing on them the input and output heat and net output work, process type (isentropic,
isobaric or isothermal).
2.
Describe the operational sequence of four stroke spark ignition (SI) and four stroke compression
ignition (CI) engines, plot the P-V and T-S diagrams for each process during the cycle with the
aid of sketches to show the mechanical operation of the piston-cylinder at each process as
follows:
a. The thermodynamics cycle must indicate the input and output heat and net output work,
process type (isentropic, isobaric or isothermal).
b. The piston-cylinder mechanical sketches must indicate the input and output heat.
c. The piston-cylinder mechanical sketches must indicate the movement of piston
(upward/downward).
d. The piston-cylinder mechanical sketches must indicate the expansion and compression.
e. The piston-cylinder mechanical sketches must indicate the air-fuel mixture intake and
exhaust gasses.
f. The piston-cylinder mechanical sketches must indicate when the spark plug is in its active
mode.
3.
What parameter would you use to measure the mechanical efficiency of two and four stroke engines and
what parameter would you fix to compare between both types. Show your explanatic
appropriate relation, compare the mechanical efficiency of both two and four stroke engines in terms of
their power-to-weight and power-to-volume ratios and provide a list showing the advantages and
disadvantages of four-stroke (4S) and two stroke (2S) engines.
using the
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 3 steps
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi…
Mechanical Engineering
ISBN:
9781305387102
Author:
Kreith, Frank; Manglik, Raj M.
Publisher:
Cengage Learning
Principles of Heat Transfer (Activate Learning wi…
Mechanical Engineering
ISBN:
9781305387102
Author:
Kreith, Frank; Manglik, Raj M.
Publisher:
Cengage Learning