【作者】

郑尊清,王梦玉,王浒,尧命发

【摘要】

中文摘要: 基于三维计算流体动力学（CFD）软件CONVERGE,耦合甲苯掺比燃料（toluene reference fuel, TRF）简化动力学机理及多步现象学碳烟模型,建立汽油压燃（GCI）的数值模拟模型。通过改变气道喷射比例、主喷时刻和预主喷间隔研究了高负荷条件下气道喷射结合缸内直喷的喷油策略对GCI燃烧及碳烟生成过程的影响。研究结果表明,增加气道喷射比例、提前主喷时刻和增大预主喷间隔都能够缩短燃烧持续期,使放热更为集中,从而降低碳烟排放；改变气道喷射比例对碳烟成核及表面生长有较大的影响,主喷时刻提前能够提高氧化速率。当气道喷射比例为40%，主喷时刻为-8°，预主喷间隔为15°时,碳烟排放为 0.0151g/(kW·h),相比试验基准工况降低了33.8%,而最大压升率也控制在可接受的范围内。 英文摘要: Based on the three-dimensional computational fluid dynamics(CFD) software CONVERGE, a computational model of gasoline compression ignition(GCI) was established by coupling reduced toluene reference fuel(TRF) chemical kinetic mechanism with a phenomenological soot model. With various port fuel injection(PFI) ratios, main injection timings and pilot-main injection intervals of direct injection(DI), the effects of the injection strategy combining PFI with DI on the combustion and soot formation processes of GCI at high load conditions were studied. The results show that higher PFI ratio, earlier main injection timing and greater pilot-main injection interval can shorten the combustion duration and increase the concentrated combustion, resulting in less soot. Besides, the PFI ratio has a great influence on soot nucleation and surface growth, and earlier main injection timing can increase the oxidation rate. With the PFI ratio of 40%, main injection timing at 8° in crank angle before the top dead center and pilot main injection interval of 15°, the soot is 0.0151 g/(kW·h), which is 33.8% lower than the baseline experimental condition, and the maximum pressure rise rate is also controlled within an acceptable range.

【论文集名称】

2020年

【会议名称】

《内燃机工程》

【下载次数】

0

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