用PDF方法求解平均温度梯度为常数的均匀剪切湍流

THE CALCULATION OF HOMOGENEOUS 'TURBULENT SHE-AR FLOW WITHIN UNIFORM MEAN TEMPERATURE GRADIENT USING PDF METHOD

本文旨在用求解速度、温度和耗散率联合几率密度函数输运方程的方法研究平均温度梯度为常数的均匀剪切湍流的性质,假定耗散率满足对数正态分布,分别用扩散过程、Langevin模型和混合模型模拟脉动压力和分子输运对耗散率、速度和温度变化的影响。用Monte Carlo求解方法得到了与实验数据基本一致的结果。

The purpose of this work is to study the homogeneous turbulent shear flow with an uniform mean temperature gradient using PDF method. It is assumed that the dissipation of turbulent energy possess the logarithmic normal distribution. The effects of pressure fluctuation and molecular transport on the evolution of the dissipation, velocity and temperature are modelled by diffusive process, Langevin model and mixing model separately. The PDF equation is solved using Monte Carlo arithmetic. The results are reasonable in agreement with the experimental data.