1. EFFECT OF COMBUSTION CHAMBER GEOMETRY
ON THE PERFORMANCE OF A CI ENGINE
NAME USN
NISHANT SARASWAT 1DS11ME060
ROHAN BANERJEE 1DS11ME084
SUMANT RANJAN 1DS11ME110
SUPRIYO SARKAR 1DS11ME111
DEPARTMENT OF MECHANICAL ENGINEERING
DAYANANDA SAGAR COLLEGE OF ENGINEERING
BATCH B9
UNDER THE GUIDANCE OF
M.R. KAMESH
ASSOCIATE PROFESSOR

2. OBJECTIVE
• DEVELOPMENT OF PISTONS- DIFFERENT
COMBUSTION CHAMBER GEOMETRY
• TESTING THE ENGINE WITH THE DIFFERENT
PISTONS
• COMPARING THE RESULTSOBTAINED WITH
THE CONVENTIONAL PISTON

3. LITERATURE SURVEY
• A comparative study of open (HCC, SCC and TCC) and re-entrant combustion
chamber geometries (SRCC and TRCC) on the performance and emission
characteristics of a diesel engine is investigated[1]
• It reduces the emissions of NOx and HCs this leads to more efficient
combustion thus controlling pollution. [2]
• Initially the isothermal performance of swirl combustors is considered, and it
is demonstrated that, the flow is often not axisymmetric but three-
dimensional time-dependent. Sufficient information is also available to
indicate that staged fuel or air entry may be used to minimize noise,
hydrocarbon, and NOx emissions from swirl combustors.[3]

4. METHODOLOGY
EVENT
1.DETAILED LITERATURE SURVEY
2.MARKET SURVEY OF READILY AVAILABLE PISTONS
3.DESIGNING OF THE PISTONS
4.FABRICATION
5.TESTING
6.RESULTS AND DISCUSSIONS

5. SPECIFICATIONS OF THE KIRLOSKAR
AV1 ENGINE
ITEM SPECIFICATIONS
ENGINE POWER 3.7 KW
CYLINDER BORE 80mm
STROKE LENGTH 110mm
ENGINE SPEED 1500 RPM
COMPRESSION RATIO 16.5:1
SWEPT VOLUME 553 cc
STROKES 4
INJECTION PRESSURE 175 bar

6. TIMELINE
OBJECTIVES DATE OF INITIATION DATE OF COMPLETION
LITERATURE SURVEY MID JANUARY 10-02-2015
MARKET SURVEY 10-02-2015 20-02-2015
DESIGN 20-02-2015 06-03-2015
FABRICATION 07-03-2015 26-03-2015
TESTING 27-03-2015 06-04-2015
MODIFICATION(IF
REQUIRED)
6-04-2015 09-04-2015
RESULTS AND DISCUSSION 10-04-2015 13-04-2015

7. MARKET SURVEY(COSTS INVOLVED)
SERIAL
NUMBER
PARTICULARS UNITS COST(INR)
1 PISTON SET 4 5200
2 FILLING 4 4000
3 FABRICATION 4 4000
4 TESTING - 2000
5 TOTAL COST - 15200

8. SWIRL AND SQUISH[4]
• Swirl : Swirl is usually defined as organized rotation of the charge about
the cylinder axis.
Swirl is created by bringing the intake flow into the cylinder with an initial
angular momentum.
• Squish : Squish is the name given to the radially inward or transverse gas
motion that occurs towards the end of the compression stroke when a
portion of the piston face and cylinder head approach each other closely.

9. NEED FOR SWIRL AND SQUISH
• UNIFORM INTAKE DUE TO INITIAL ANGULAR
MOMENTUM
• RAPID MIXING OF THE AIR MIXTURE AND INJECTED
FUEL
• SPEEDS UP THE COMBUSTION PROCESS
• IMPROVES SCAVENGING

11. MODIFICATIONS
We modify the combustion chamber of the basic AV1 piston into the
following types.
For all the combustion chamber configurations bowl volume is kept constant.

12. EXPERIMENTAL PROOF OF CONSTANT BOWL VOLUME
• The bowl volume is kept constant to approximately 21cc.
• As a visual proof to this, the hemispherical piston is filled with blue ink.
• The same amount of ink is transferred to all the other pistons with varying
combustion chamber geometries using a syringe.
• It is found out that the volume of all pistons is constant.

13. BASIC COMBUSTION CHAMBER GEOMETRY
The basic shape of the combustion chamber is
hemispherical in a Kirloskar AV1 piston
Combustion chamber
Compression rings
Oil ring

14. EXPERIMENTAL SETUP

16. EXPERIMENTAL CONDITIONS
• INJECTION PRESSURE : 175 bar
• EGR : OFF
• AIR PREHEATER : OFF
• ENGINE COOLING WATER : 2lpm
• CALORIMETER COOLING WATER : 2.5lpm

17. DESIGN OF SHALLOW COMBUSTION CHAMBER
INITIAL GEOMETRY (HCC) FINAL GEOMETRY (SCC)
(SECTIONAL FRONT VIEW)

18. THE PISTON(SCC) BEFORE TESTING

19. THE PISTON (SCC) AFTER TESTING
Image : Injection spots
after combustion.

20. DESIGN OF TOROIDAL COMBUSTION CHAMBER
INITIAL GEOMETRY (HCC) FINAL GEOMETRY (TCC)
(SECTIONAL FRONT VIEW)

21. THE PISTON (TCC) BEFORE TESTING

22. THE PISTON (TCC) AFTER TESTING
Image : Injection spots
after combustion.

23. AIR FLOW IN RE-ENTRANT TYPE
COMBUSTION CHAMBERS
• A re-entrant bowl is used to promote more rapid air fuel
mixing in the bowl.
• Conventional bowl : Swirling air enters the bowl and flows
down to the base of the bowl then inward and upward in
toroidal motion
• Re-entrant bowl : Swirling air enters the bowl and spreads
downwards and outwards into the undercut region and
divides into a stream rising up the bowl sides and a stream
flowing along the bowl base.

24. DESIGN OF TOROIDAL RE-ENTRANT TYPE COMBUSTION CHAMBER
INITIAL GEOMETRY (HCC) FINAL GEOMETRY(TRCC)
(SECTIONAL FRONT VIEW)

25. THE PISTON (TRCC) BEFORE TESTING

26. THE PISTON (TRCC) AFTER TESTING

27. DESIGN OF SHALLOW RE-ENTRANT TYPE COMBUSTION CHAMBER
(IEW)
INITIAL GEOMETRY (HCC)
FINAL GEOMETRY(SRCC)
(SECTIONAL FRONT VIEW)

28. THE PISTON (SRCC) BEFORE TESTING

29. THE PISTON (SRCC) AFTER TESTING

30. FRICTIONAL POWER TCC PISTON

31. FRICTIONAL POWER TRCC PISTON

32. FRICTIONAL POWER SCC PISTON

33. FRICTIONAL POWER SRCC

34. COMPARISON OF FRICTIONAL POWER
TYPE OF PISTON FRICTIONAL POWER (KW)
TCC 3.5
TRCC 3.6
SCC 4.6
SRCC 3.2

35. COMPARISON OF LOAD vs MECHANICAL EFFICIENCY
(%)

37. COMPARISON OF BRAKE THERMAL
EFFICIENCY(%) WITH LOAD

38. COMPARISON OF SFC WITH LOAD

40. FUTURE SCOPE
THE EXPERIMENT CAN BE FURTHER ON BE EXTENDED TO THE
FOLLOWING CONDITIONS.
• VARYING INJECTION PRESSURE.
• WITH THE PRESENCE OF EGR.
• WITH PREHEATED INTAKE AIR.
• VARYING COMPRESSION RATIOS.

41. CONCLUSION
• CONSIDERABLE IMPROVEMENT IS SEEN IN
THE MECHANICAL EFFICIENCIES OF THREE
PISTONS OVER THE STOCK PISTON
• SFC IS OBSERVED TO BE HIGH AT LOWER
LOADS BUT AT HIGHER LOADS, IT IS ALMOST
THE SAME AS THE STOCK PISTON(HAVING
MORE MECHANICAL EFFICIENCY )

42. BIBLIOGRAPHY
[1]S.Jaichandar, K.Annamalai and P.Arikaran."Comparative evaluation of pongamia
biodiesel with open and re-entrant combustion chambers in a DI diesel engine",
International journal of automotive engineering and technology, Volume 3 issue 2
pp66-73 2014.
[2] Rehman H. , Phadatare A.G., "Diesel engine emissions and performance fropm
blends of Karanja Methyl Ester and Diesel", Biomass and Bioenergy 29:393-397,
2004
[3]B.V.V.S.U.Prasad,C.S.Sharma,T.N.C.Anand, R.V.Ravikrishna."High swirl inducing
piston bowls in small diesel engine for emission reduction." Applied energy, Elsvier
88 2355-2367 2011.
[4]John B. Heywood . "International combustion engine fundamentals." New York; Mc
Graw Hill Book Company 1988.

43. [5] Jayashankara B, Ganesan V, "Effect of fuel injection timing and initial intake
pressure on a performance of DI diesel engine". Energy converse manage 2010;
51(10); 1835-48.
[6]Zhengbai L, Xinqun G. "Investigation of effect of piston bowl and fuel injector
offsets on combustion and offset DI diesel engines." SAE paper 2002-01-1748.
[7]Philip WS, Ruthland CJ, "modeling the effect of flow characteristics on diesel engine
combustion." SAE paper 950282.