论文部分内容阅读
现象学燃烧模型是一种准维模型。由于进行了分区处理并考虑了较多与燃烧过程有关的因素，所以可在一定程度上预测排放。但其预测结果精度受到诸多参数的影响。本文在将它应用到有较强进气涡流的小缸径高速直喷式柴油机上时特别计及了进气涡流强度对各区之间质量传递的影响，在模型构建中，摸清了若干燃烧组织的重要参数对模型预测结果精度的影响。本文分别讨论了这些参数对输出结果的影响，并将部分计算结果与实测结果进行了对比。结果表明：各参数的影响不一，其中掺混系数β由于对传质量影响较大，从而影响各区内的温度而对氮氧化物预测精度的影响最大。因此，提高模型预测精度的关键是正确选取各参数值。
Phenomenological combustion model is a quasi-dimensional model. As a result of the zoning process and taking into account more of the factors associated with the combustion process, it is possible to predict emissions to some extent. However, the accuracy of its prediction is affected by many parameters. In this paper, when it is applied to a small bore high-speed direct-injection diesel engine with strong intake vortex, the influence of intake vortex intensity on the mass transfer between the zones is especially taken into account. In the model construction, some combustion tissues The influence of the important parameters on the accuracy of the model prediction. This paper separately discusses the influence of these parameters on the output results, and compares some of the calculated results with the measured results. The results show that the influence of each parameter is different. The blending coefficient β has the greatest influence on the prediction accuracy of nitrogen oxides due to the large influence on the mass transfer, which affects the temperature in each area. Therefore, the key to improve the accuracy of model prediction is to correctly select the value of each parameter.