Methodology to Characterise the Mixture Preparation and Ignitability in the Combustion Chamber of 2-Stroke GDI Engines

Activity: Talk or presentationTalk at conference or symposiumScience to public


Four stroke engines using GDI mixture preparation systems have been standard in passenger cars for many years. In the field of high performance two-stroke engines, this development is still in its beginnings, although the use of internal mixture preparation, even for high-speed sport engines, can be advantageous.
The complexity of internal mixture preparation with its additional injection parameters requires the use of CFD-simulation tools. A characterisation of combustion robustness especially for stratified mixture preparation is not possible using global parameters and standard visualization techniques. To overcome this deficiency of the standard CFD evaluation method, a methodology to evaluate the ignitability and robustness of the combustion process was developed by introducing a sphere assessment technique.
In this presentation the two-stroke GDI combustion concept is explained in the introduction together with its boundary conditions. In the main part, the CFD simulation methodology is described and the novel evaluation methodology is explained in detail using the example of a high performance two-stroke GDI engine with variation in injection parameters. In the summary, the results of the CFD investigations are compared to dynamometer test results.
Period13 Sep 2022
Event titleDIRECT INJECTION 2-STROKE ENGINES INTERNATIONAL CONFERENCE: On the way to zero emissions & carbon neutral operation!
Event typeConference
Conference number2022
LocationValencia, SpainShow on map
Degree of RecognitionInternational


  • 2-Stroke Engines
  • GDI
  • Gasoline direct injection
  • high-speed sport engines
  • CFD simulation