1. Performance Analysis of HCCI-DI I.C. Engines for Automobiles
P M V Subbarao
Professor
Mechanical Engineering Department
I I T Delhi
Means to Achieve Low Emission with High Fuel Economy…..

2. Engine specifications
Schematic test setup
Engine specifications

3. Combustion Analysis thru Pressure-Crank Angle Diagram
Identification of Different Combustion Parameters

4. In-cylinder Processes in a Diesel Engine

5. Modeling of Combustion Process
In above Eq., the rate of the heat loss Qloss/dθ is expressed as:
The convective heat transfer coefficient is given by the Woschni model as
For combustion and expansion processes: C1=

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

8. In-cylinder Processes in a Mild HCCI-DI Engine

9. In-cylinder Processes in a Moderate HCCI-DI Engine
SAE paper

10. In-cylinder Processes in a Harsh HCCI-DI Engine

11. Control of Particulates thru HCCI

12. Selection of safe Split Ratio

13. Evolution of CI Engine from Polite to Aggressive Attitude

14. Belligerent Nature of HCCI Engine

15. Evolution of Onset of Combustion

16. Selection of Pilot Injection Timing

17. Selection of PIT : For Safe Combustion

18. Selection of PIT : For Safe Combustion

19. Eco-friendly Nature of HCCI-DI : 80% Split Ratio

20. Eco-friendly Nature of HCCI-DI : 80% Split Ratio

21. Degree of Homogenization

22. Need for Exhaust Gas recirculation

23. Need for Fuel Heating

24. High Speed Operation of HCCI-DI Engine

25. HCCI-DI Engine is a Consciously Knocking Engine
The slope of RI for pure HCCI (100% premixed) combustion will be much steeper than 80% and 95% split ratio.

26. HCCI-DI is a Consciously Knocking Engine
Corresponding RI was 2.94 W/m2 and 13.5 W/m2.
Only 0.7 bar IMEP increase leads to 4 times increase in RI !!!
This RI (13.5 W/m2) is about 8 times higher to the baseline combustion at similar load condition.
The slope of RI for pure HCCI combustion will be much steeper than 80% and 95% split ratio.

27. Final Recommendations
LNV of IMEP is used to address the issue of misfire as suggested by Industry.
It is defined as the ratio of minimum value to the average value of the parameter of interest.
COV of IMEP beyond 4 bar IMEP condition is found within 5%.
COV for baseline combustion remains around 3% irrespective of load.

28. Our HCCI-DI Publications
Journals/ Articles
1. Pranab Das, Mayur V. Selokar, PMV Subbarao, JP Subrahmanyam. Effect of Injection Timing, Premixed Equivalence Ratio and EGR on Combustion Characteristics of an HCCI-DI Combustion Engine using In-cylinder Dual Injection strategy. SAE Technical Paper , doi: /
2. Pranab Das, PMV Subbarao, JP Subrahmanyam , “Control of Combustion Process in an HCCI-DI combustion Engine Using Dual Injection Strategy with EGR” . Fuel 159 (2015) 580–589, doi /j.fuel
3. Pranab Das, PMV Subbarao, JP Subrahmanyam “Effect of Main Injection Timing for controlling the combustion phasing of a Homogeneous Charge compression ignition engine using a new dual injection strategy”. Energy Conversion and Management 95 (2015) 248–258, 2015.
4. Pranab Das, PMV Subbarao, JP Subrahmanyam, “Effect of Cetane Number and Fuel Properties on Combustion and Emission Characteristics of an HCCI-DI Combustion Engine Using a Novel Dual Injection Strategy”. SAE Technical Paper , 2015, Doi: /
5. Pranab Das, PMV Subbarao, JP Subrahmanyam, “Study of Combustion Behavior and Combustion Stability of HCCI-DI Combustion for a Wide Operating Range Using a Low Cost Novel Experimental Technique” SAE Technical Paper , 2014, doi: /
Conferences
1. Pranab Das, A new experimental approach to achieve controlled HCCI-DI combustion by in-cylinder multi injection strategy. Symposium on International Automotive Technology 2015 (SIAT 2015), Poster paper No AE-4, 2015.
2. Pranab Das, Mayur V Selokar, Anand Kumar, PMV Subbarao, JP Subrahmanyam, “Experimental Studies on Combustion Behavior of Different Premixed Fuel using Dual Injection Strategy”, 23rd National Conference on I. C. Engines and Combustion, Paper no 2013NCICEC0105, 2013.
3. Pranab Das, PMV Subbarao, JP Subrahmanyam, “Effect of Premixed Ratio on Combustion and Emission Characteristics of HCCI-DI Engine using Multi Injection Strategy”, International Conference on Recent Trends in Mechanical Engineering (RTME-2013), pp , 2013.
4. J.P.Subrahmanyam, Pranab Das, P.M.V. Subbarao, “Recent Trends in Homogeneous Charge Compression Ignition Engines”, National conference on Emerging Trends in Mechanical Engineering (ETME-2012), pp , 2012.
Awards/ Recognitions
1. Received best paper award at Symposium on International Automotive Technology (SIAT) 2015 during January, 2015 organized by ARAI, Pune in association with SAE International.
2. Received a one week full sponsored research training award at Cummins, Darlington Engine Plant fully sponsored by Cummins India Ltd.
Journal/ Articles under review/communicated
1. Pranab Das, PMV Subbarao, JP Subrahmanyam. Investigation of Various Injection Strategies to Understand Combustion, Performance and Emission Behavior of CIDI, HCCI-DI and LTC combustion engine. SAE Technical Paper

29. Conclusions HCCI Engine Technology is an obvious future choice.
Extensive CAD is essential for the development of HCCI Engines.
CAD combined with experimental study will develop a better engine with faster development cycle.
More avenues for future research and development.