Finished Research Project
Project title: Direct Injection Hydrogen Assisted Stratified
Charge Engine. The project started in may 2004 and ended in 2009 with the presentation of the Ph.D. thesis: "HCCI combustion using charge stratification and spark-assistance"(download (pdf - 305 pages)). The project wais financially supported by
STEM, the Swedish Energy Agency.
Project participants: Professor Ingemar Denbratt (supervisor),
Associate Professor Valeri Golovitchev (co-supervisor) and Andreas Berntsson.
I am involved in a project that has the goal of creating internal
combustion engines with better fuel efficiency and lower emissions.
The project aims for increased control of HCCI combustion, since
HCCI combustion displays positive features such as low NOx emissions
and low fuel consumption. This control is achieved by creating
a hybrid combustion concept, combining HCCI combustion with
SI combustion of a stratified charge. The SI stratified charge
acts as a control device over the HCCI combustion, the early
flame propagation adds heat during the compression and this
heat is used to control the HCCI combustion. Since the combustion
initially consists of SI combustion and subsequently of HCCI
combustion, very lean mixtures can be used for the stratified
charge due to that if any fuel escapes the initial SI combustion
it will be combusted in the HCCI combustion. Thus the SI combustions
contribution in NOx emissions have been low. The role of fuel
stratification in it self have also been studied.
To initiate HCCI combustion in engines using SI engine geometry
and petrol-like fuel NVO have be used for the latest studies.
Detailed optical studies have been performed on the reaction
occuring during the NVO when pilot injections prior to the NVO
was used. Furthermore have the combination of the control methods
developed in the first two papers and NVO been investigated.
The image displays the project idea: initial SI combustion
and subsequently HCCI combustion.
Berntsson, A., Denbratt, I., "Spark Assisted HCCI Combustion
Using a Stratified Hydrogen Charge", SAE Technical Paper
Series, SAE Paper 2005-24-039.
Berntsson, A., Denbratt, I., "HCCI Combustion Using a
Spark Ignited Stratified Charge", Proceedings. JSAE Annual
Congress JSAE Technical Paper Series, 20065424.
Berntsson, W., A., Denbratt, I., "HCCI Combustion Using
Charge Stratification for Combustion Control", SAE Technical
Paper Series, SAE Paper 2007-01-0210.
Berntsson, W., A., "An Experimental Study of a Spark-assisted
Stratified Charge HCCI Engine", Licentiate Thesis, ISSN
Berntsson, W., A., Denbratt, I., "Optical Study of HCCI
Combustion Using NVO and an SI Stratified Charge", SAE
Technical Paper Series, SAE Paper 2007-24-0012.
Berntsson, W., A., Andersson, M., Dahl, D., Denbratt, I., "LIF
for OH imaging in the Negative Valve Overlap of a HCCI Combustion
Engine", The Spark Ignition Engine of the Future Conference,
SIA Technical Paper.
Berntsson, W., A., Andersson, M., Dahl, D., Denbratt, I., "A
LIF-study of OH in the Negative Valve Overlap of a Spark-assisted
HCCI Combustion Engine", SAE Technical Paper Series, SAE
Dahl, D., Andersson, M., Berntsson, W.,A., Denbratt, I., Koopmans, L., "Reducing Pressure Fluctuations at High Loads by Means of Charge Stratification in HCCI Combustion with Negative Valve Overlap", SAE Technical Paper Series, SAE
Berntsson, W., A., Andersson, M., Dahl, D., Denbratt, I., "Characterization of an HCCI Engine Using Charge
Stratification and Spark-Assist by Simultaneous PIV, Multi-Species
LIF and High Speed Video Analysis" submitted for publication.
most of the work can be found by searching at google-scholar with "HCCI Berntsson"
As institutional duty I have been the project leader of Chalmers
Formula Student for the team 2005 and 2006. Chalmers Formula
Student is a 10 p course at Chalmers, with the goal of creating
a formula car prototype that meets the regulations for a formula
SAE car. During my period the team has perticipated in the UK
competition Formula Student 2005 and 2006, in the US competition
FSAEW 2006 and the Baltic Open in Finland 2006.
Best results: Total 2nd place in the Baltic open 2006, where
we beat the world champions in acceleration with a world record
time of 3.75 s from 0 to 75 m (the world record time was 3.8
The black car is the car that was built by the 2006 team (picture
taken at the Baltic Open in Finland) and the blue car is the
car that was built by the 2005 team (picture taken at California
Speedway in the USA). Chalmers have also perticipated in the
2005 and 2006 event in the UK with the cars seen above.
The good results in Finland for the black car prepared the
way for further races and below the car can be seen on the California
Speedway track in Los Angeles. I am the one wearing a cap and
holding the flag.