Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D....
Transcript of Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D....
![Page 1: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/1.jpg)
1
Internal Combustion Engines
Lecture-28
Ujjwal K Saha, Ph.D.Department of Mechanical Engineering
Indian Institute of Technology Guwahati
Prepared underQIP-CD Cell Project
![Page 2: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/2.jpg)
2
• Shortage of liquid fuel and gaseous fuels being cheaper than liquid fuels gave birth to dual fuel engines.• From recent air and water pollution concern it became necessary to utilize sewage gas.• Gaseous fuels have high self-ignition temperature and burn efficiently.
Introduction
![Page 3: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/3.jpg)
3
Duel-fuel operation combines the possibility of operating a diesel engine on liquid fuels such as diesel oil or gas oil and on gaseous fuels such as natural gas, sewage gas and cook oven gas.
![Page 4: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/4.jpg)
4
Working Principle
• Works on diesel cycle.• Gaseous fuel (primary fuel) is added to air
inducted into the engine or supplied by supercharger.
• The mixture of air and gaseous fuel gets compressed in the cylinder.
• Liquid fuel called pilot fuel injected near the TDC acts as a source of ignition.
• Gas-air mixture ignites establishing a number of flame-fronts.
• In a dual-fuel engine combustion starts similar to CI engine, but it is propagated by flame-fronts as in SI engine.
![Page 5: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/5.jpg)
5
Working Principle
![Page 6: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/6.jpg)
6
Gas mode• High efficiency and low
emissions• Automatic and instant
transfer to diesel operation in alarm situations
• Transfer to diesel operation at any load
Diesel mode• As an ordinary diesel engine• Transfer to gas operation preferably at part
load• Pilot fuel injection in operation
![Page 7: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/7.jpg)
7
Performance of Dual-Fuel engines
• Produce equal power when operating on liquid fuels as with gaseous fuel.
• Dual fuel engines are slightly more efficient to conventional diesel at full load.
• However, the maximum output is about the same.
• Efficiency of dual in part load is slightly poor.
• Typical diesel efficiency is 41%, and dual efficiency is 38.5.
![Page 8: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/8.jpg)
8
Advantages of Dual Fuel Engines
• Efficient utilization of cheap gas available from various sources.
• Gas burns without leaving any residue (no pollution).
• Clean combustion results in reduced wear of engine parts and reduced consumption of lubricating oil.
![Page 9: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/9.jpg)
9
Advantages of Dual Fuel Engines
• Increased utility of the power plant as the versatility of change-over from gas to diesel and vice-versa.
• Only a small amount of liquid fuel needed to run engine.
• Suitable for total energy installation (sewage gas)
![Page 10: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/10.jpg)
10
Advantages of Dual Fuel Engines
• Can be used to produce synthetic gas, which is a mixture of CO and H2.
• Ideal for LPG tankers as they can utilize the gas which evaporates.
![Page 11: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/11.jpg)
11
Factors affecting combustion in a dual fuel engine
• Pilot fuel quantity
![Page 12: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/12.jpg)
12
![Page 13: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/13.jpg)
13
• Injection timing
![Page 14: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/14.jpg)
14
• Effect of Cetane number• Effect of inlet temperature
![Page 15: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/15.jpg)
15
![Page 16: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/16.jpg)
16
• Effect of type of gaseous fuels
![Page 17: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/17.jpg)
17
• Effect of throttling• Effect of mixture strength
![Page 18: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/18.jpg)
18
Main type of gaseous fuel & their requirement
• Natural gas • Sewage gas• LPG• Town gas• Hydrogen gas
• Clean• Dry• Minimum calorific value
gas 4500 kcl/cm3
light fuel oil 10,200 kcl/kg
![Page 19: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/19.jpg)
19
Knock control in dual engine
• Excess supply of air• Use of cold combustion air• Increased cooling of piston• Use of additives• Reducing the pressure of the
gaseous fuel
![Page 20: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/20.jpg)
20
Multi-fuel Engines
• A multi-fuel engine is one which would operate satisfactorily with substantially unchanged performance and efficiency, on a wide verity of fuels ranging from diesel oil, crude oil to lighter fuels like gasoline and even normal lubrication oil.
• Mainly developed for military requirements.
• Has good idling and part load efficiency and low exhaust smoke.
![Page 21: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/21.jpg)
21
• Should have high compression ratios as gasoline have low cetane numbers.
• Must be capable of starting at subzero temperatures.
• Large stroke/bore ratio gives a compact combustion chamber so that it remains hot in all conditions of speed.
• An open combustion chamber is suited as in a pre-combustion chamber, additional heat losses due to throat occur (e.g., spherical or M-combustion chamber).
![Page 22: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/22.jpg)
22
Difficulties• Tendency of vapor lock while using
lighter fuels.• Tendency of increased wear due to
lower lubricity of gasoline.• Requirements for injecting different
volumes of fuel depending on their heating values and compressibility.
![Page 23: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/23.jpg)
23
1.1. Crouse WH, and Anglin DLCrouse WH, and Anglin DL, (1985), Automotive Engines, Tata McGraw Hill.2.2. FergusanFergusan CR, and Kirkpatrick ATCR, and Kirkpatrick AT,, (2001), Internal Combustion Engines,
John Wiley & Sons.3.3. Gill PW, Smith JH, and Ziurys EJGill PW, Smith JH, and Ziurys EJ,, (1959), Fundamentals of I. C. Engines,
Oxford and IBH Pub Ltd. 4.4. Heisler H,Heisler H, (1999), Vehicle and Engine Technology, Arnold Publishers.5.5. Heywood JB,Heywood JB, (1989), Internal Combustion Engine Fundamentals, McGraw Hill.6.6. Heywood JB, and Sher E,Heywood JB, and Sher E, (1999), The Two-Stroke Cycle Engine, Taylor &
Francis.7.7. MathurMathur ML, and Sharma RP,ML, and Sharma RP, (1994), A Course in Internal Combustion
Engines, Dhanpat Rai & Sons, New Delhi.8.8. Pulkrabek WW,Pulkrabek WW, (1997), Engineering Fundamentals of the I. C. Engine, Prentice
Hall.9.9. Rogers GFC, and Mayhew YRRogers GFC, and Mayhew YR, (1992), Engineering Thermodynamics, Addison
Wisley. 10.10. Stone R,Stone R, (1992), Internal Combustion Engines, The Macmillan Press Limited,
London.11.11. Taylor CF,Taylor CF, (1985), The Internal-Combustion Engine in Theory and Practice, Vol. 1
& 2, The MIT Press, Cambridge, Massachusetts.
References
![Page 24: Internal Combustion · PDF file1 Internal Combustion Engines Lecture-28 Ujjwal K Saha, Ph.D. Department of Mechanical Engineering Indian Institute of Technology Guwahati Prepared under](https://reader037.fdocuments.us/reader037/viewer/2022102522/5a70289a7f8b9ab1538bb49f/html5/thumbnails/24.jpg)
24
1. http://www.mne.psu.edu/simpson/courses2. http://me.queensu.ca/courses 3. http://www.eng.fsu.edu4. http://www.personal.utulsa.edu5. http://www.glenroseffa.org/6. http://www.howstuffworks.com7. http://www.me.psu.edu 8. http://www.uic.edu/classes/me/ me429/lecture-air-cyc-web%5B1%5D.ppt9. http://www.osti.gov/fcvt/HETE2004/Stable.pdf10. http://www.rmi.org/sitepages/pid457.php11. http://www.tpub.com/content/engine/14081/css12. http://webpages.csus.edu13. http://www.nebo.edu/misc/learning_resources/ ppt/6-1214. http://netlogo.modelingcomplexity.org/Small_engines.ppt15. http://www.ku.edu/~kunrotc/academics/180/Lesson%2008%20Diesel.ppt16. http://navsci.berkeley.edu/NS10/PPT/ 17. http://www.career-center.org/ secondary/powerpoint/sge-parts.ppt18. http://mcdetflw.tecom.usmc.mil19. http://ferl.becta.org.uk/display.cfm20. http://www.eng.fsu.edu/ME_senior_design/2002/folder14/ccd/Combustion21. http://www.me.udel.edu22. http://online.physics.uiuc.edu/courses/phys14023. http://widget.ecn.purdue.edu/~yanchen/ME200/ME200-8.ppt -
Web Resources