1. Free Religious Automotive I C Engines
P M V Subbarao
Professor
Mechanical Engineering Department
I I T Delhi
Controlled Combustion in CI & SI engines…..

2. CI Religion in I.C. Engines
Diesel Engines
 High CR
 No throttling , quality governed,
High fuel economy at part load
Best suited for low SIT fuels
Very good faster reacting fuels
Low HC emissions
Low specific power
Heterogeneous combustion
High NOx and PM (Smoke)

3. SI Religion in I.C. Engines
MPFI Engines
High Specific Power
Homogeneous combustion
Very Low PM & low Nox
Best suited for High SIT Fuels
Very good for slow reacting fuels
High HC emissions
Poor performance at part load

4. The Free Religious Engine
BEST Qualities of Two Religions in I.C. Engines
The Free Religious Engine
High power at full load  High CR, high vol.
High Fuel economy  Distinctly stratified charge,
Quality governing
Lower HC, PM & NOx.

5. Next generation Engines
GDI

6. Need for Next Generation CI Engines
Strict emission regulations
Efficient utilization of energy resources
The conventional diffusion combustion can not meet upcoming stringent emission norms (Higher Smoke and NOx emissions )
Banning of Diesel engines across various Cities world wide regardless of their high efficiency and power out put (e.g. Delhi, Chandigarh)
Emerging topic worldwide to keep the High efficiency diesel fuelled vehicles rolling on the roads

7. Eco-friendly Equivalence Ratio for CI Combustion

8. The Holistic Combustion Method
Fuel & Air Charge Undergoes Compression
Spontaneous Reaction Throughout Cylinder
Low Temperature and Fast Reaction Gives Low NOx

9. Mildly Knocking Eco-firendly Engine

10. Homogeneous Charged Combustion
To achieve the kind of combustion depicted in previous discussion;
Three major aspects should be addressed:
1. How to create a homogeneous mixture in a CI engine?
2. How to achieve self ignition of this mixture?
3. How to control combustion so that engine is safe and performance is better?

11. Effect of mixing time on Early (pilot) injection on combustion process

12. Advanced CI Engine for Next Decade
HCCI-DI Engine.
Divide the fuel into Primary (main) and Pilot (Early) Fuel.
Pilot fuel is responsible for homogenization.
Primary fuel is responsible for Compression Ignition.
Identify the conditions for avoidance of Self Ignition due to Pilot fuel Injection.
How to develop a dual injection system????

13. Developed HCCI-DI fuel injection system
External pump (Pilot)
2 pumps
Belt drive from extended
cam shaft
Fuel injector
HP pipe 1, 2 and 3
T-junction
Split ratio control lever
Inj. timing control cam
Developed System
Multi injection using single Injector without any geometry modification

14. Schematic Diagram of HCCI-DI Engine test setup
Engine specifications

15. Dual Injection HCCI Engines

16. Temporal Evolution of Spatial Distribution of Equivalence Ratio during Pilot Injection0.
rcylinder

17. Temporal Evolution of Spatial Distribution of Equivalence Ratio during main injection
2.4
2.0
1.6
1.2
0.8
0.4
0.0
rcylinder

18. Eco-friendly Equivalence Ratio for CI Combustion

19. Diagnostic Testing of HCCI-DI Engine

20. Rate of Combustion (Heat Release rate) in a Diesel Engine

21. In-cylinder Processes in a Mild HCCI Engine

22. Pace of Combustion in a Mild HCCI-DI Engine