考虑化学反应的标量耗散率及其在PDF小尺度混合模型中的应用

Study of Scalar Dissipation Rate with Reaction and Its Application in Molecular Mixing Model in PDF Equation

在 Sanders和 Borghi工作的基础上 ,推导出考虑化学反应的标量耗散率和标量时间尺度 ,在标量的联合概率密度函数方程的小尺度混合模型中采用考虑化学反应的标量的时间尺度 ,结合求解流场的 k- ε模型对甲烷轴对称射流扩散火焰进行了计算 ,最后分析了标量时间尺度对小尺度混合模型 (IEM模型 )和计算结果的影响。

Based on the study of Sanders and Borghi,two simple models of scalar dissipation rate and scalar time scale which take account of the influence of chemical reaction were obtained.Then,the joint scalar probability density function (PDF) approach was employed together with k ε model to compute turbulent diffusion flames using the time scale with reaction in IEM mixing model.It was suggested that the influence of chemical reaction on scalar time scale cant be neglected,and the mixing model can be improved by using the time scale in which the effect of reaction is taken into account.