非线性代数应力模型在内燃机缸内湍流计算中应用

Application of nonlinear algebraic stress model to in-cylinder turbulent flows in ICE

利用张量不变性原理建立一个非线性代数应力模型 ,它包含了平均流变形率张量和旋转张量三阶项的影响 .模型中压力应变项是基于 Lee由快速畸变理论导出的解析解 ,通过引入参考总应变而包含了平均流变化的历史效应 .湍能及其耗散率的求解采用 RNG k-ε模型 .用此模型对几种内燃机缸内的流场进行计算 ,结果表明此模型在定量和定性上较之 k-ε模型和基于

A nonlinear algebraic stress model has been set up by applying the tensor invariance theory, in which the effects of the cubic terms of the strain rate tensor and the rotation tensor of the mean flow on the Reynolds stress are incorporated. The pressure strain correlation is simulated based on the analytic solution from the rapid distortion theory by Lee. The effects of the mean flow distortion history are included in the model by introducing a parameter of the reference total strain. The turbulent kinetic energy and its dissipation rate are solved by using the RNG k ε model. Numerical results for in cylinder flows of several engines show that the new model may give better prediction than the k ε model and the ASM based on LRR model.