直喷式柴油机气缸内各向异性紊流模拟和试验研究

Modeling and Experimental Investigation on Nonisotropic Turbulence in the Cylinder of a Direet Injection Diesel Engine

本文发展了一种模拟在喷式柴油机气缸内各向异性紊流的方法。在建立雷诺应力表达式中，没有采用标准的Ｋ－ε紊流模型所做的各向同性假设，从紊流的随机性质出发导出适合于各向异性紊流的雷诺应力表达式。对一个轴对称缩口形燃烧室在压缩过程中的流动情况进行了模拟和实际测量。计算与实测结果的对比表明，预测模型及方法有较好的精度。文中还对缸内紊流分布的特点进行了讨论。

A method of modeling nonisotropic turbulence in the cylinder of a D.I.diesel engine is developed.Based on the stochastic theroy of turbulence,the eddy viscocity in K-ε model is modified and the turbulent kinetic energy-dissipation-random model of Renolds stress which can solve nonisotropic turbulence is given.The calculated data were compared to the experimental data obtained on a axisymmetric reentrant bowl chamber of a D.I.diesel engine.The calculated results of the model established were compared with the experimental data and showed a good agreement.