【作者】

Ioannis Vlaskos

【摘要】

该论文已在赫尔辛基举行的第28届CIMAC大会上发表，论文的版权归CIMAC所有。ABSTRACT Increasingly demanding efficiency requirements on new high BMEP gas engines are driving the trend of the development of modern high and medium speed engines toward natural gas [NG] lean burn combustion systems which are characterized by a very efficient combustion and long operating intervals while keeping the NOx emissions at a very low level. A design process and design criteria for an efficient combustion based on Ricardo experience and guidelines applied in the design and evaluation of gas engines with pre-chambers will be described in this paper, focusing on prechamber features like nozzle design, spark plug position or interaction between the cylinder and pre-chamber flow. Following the design process, this article will illustrate the necessary analytical steps required for an efficient gas combustion system design in terms of both pre-chamber and main chamber and will provide information of typical misconceptions that could appear in the design of such systems. Additionally to the pre-chamber combustion performance, the paper will show the influence of the pre-chamber combustion on its structure and durability using thermo-structural simulations, also utilizing the outputs of CFD combustion analysis. For prediction of thermo-structurally driven pre-chamber surface degradation (like cases where significant amount of porosity throughout the thickness is spotted), carrying out a transient thermal analysis followed with a structural stressfatigue analysis using transient results is investigated to address the issues. Transient thermo-structural analysis of the pre-chambers is proposed using full-cycle CFD data from in-cylinder CFD analysis as boundary condition. This approach is intended as a supplement to the existing standard steady-state thermo-structural analysis in order to address the above mentioned issues.

【会议名称】

第28届CIMAC会议

【会议地点】

芬兰 赫尔辛基

【下载次数】

4

返回