Improvement of combustion and exhaust gas emissions in a passenger car diesel engine by modification of combustion chamber design

Takashi Kaminaga, Jin Kusaka

Research output: Contribution to journalConference article

5 Citations (Scopus)


Three types of combustion chamber configurations (Types A, B, and C) with compression ratio lower than that of the baseline were tested for improved performance and exhaust gas emissions from an inline-four-cylinder 1.7-liter common-rail diesel engine manufactured for use with passenger cars. First, three combustion chambers were examined numerically using CFD code. Second, engine tests were conducted by using Type B combustion chamber, which is expected to have the best performance and exhaust gas emissions of all. As a result, 80% of NOx emissions at both low and medium loads at 1500 rpm, the engine speed used frequently in the actual city driving, improved with nearly no degradation in smoke emissions and brake thermal efficiency. It was shown that a large amount of cooled EGR enables NOx-free combustion with long ignition delay. In addition, the low compression ratio piston led to 22% improvement on maximum torque at the same engine speed without increasing maximum cylinder pressure.

Original languageEnglish
JournalSAE Technical Papers
Publication statusPublished - 2006 Jan 1
EventPowertrain and Fluid Systems Conference and Exhibition - Toronto, ON, Canada
Duration: 2006 Oct 162006 Oct 19


ASJC Scopus subject areas

  • Automotive Engineering
  • Safety, Risk, Reliability and Quality
  • Pollution
  • Industrial and Manufacturing Engineering

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