CFD Simulations of Pre-Chamber Jets' Mixing Characteristics in a Heavy Duty Natural Gas Engine

Summary, in English

The effect of pre-chamber volume and nozzle diameter on performance of pre-chamber ignition device in a heavy duty natural gas engine has previously been studied by the authors. From the analysis of recorded pre- and main chamber pressure traces, it was observed that a pre-chamber with a larger volume reduced flame development angle and combustion duration while at a given pre-chamber volume, smaller nozzle diameters provided better ignition in the main chamber. The structure of pre-chamber jet and its mixing characteristics with the main chamber charge are believed to play a vital role, and hence CFD simulations are performed to study the fluid dynamic aspects of interaction between the pre-chamber jet and main chamber charge during the period of flame development angle, i.e. before main chamber ignition. It has been observed that jets from a larger pre-chamber penetrates through the main chamber faster due to higher momentum and generates turbulence in the main chamber earlier. At a given pre-chamber volume, smaller nozzle diameter causes higher velocity jet also causing high turbulence built up and better distribution of active species from the pre-chamber into the main chamber.

• Author: Ashish Shah; Per Tunestål; Bengt Johansson
• Department/s: Combustion Engines
• Publishing year: 2015
• Language: English
• Publication/Series: [Host publication title missing]
• Links: http://dx.doi.org/10.4271/2015-01-1890
• Document type: Conference paper
• Publisher: Society of Automotive Engineers
• Topic: Mechanical Engineering
• Keywords: Internal combustion engines; ignition system; pre-chamber ignition; CFD simulation
• Conference name: JSAE/SAE Powertrain, Fuels and Lubricants International Meeting, 2015
• Conference date: 2015-09-01 - 2015-09-04
• Conference place: Kyoto, Japan
• Status: Published
• Project: Competence Centre for Combustion Processes
• Research group: KCFP