一种改进的漂移系数模型及其应用研究

A modified drift coefficient model and its application

对轴对称突扩通道内气粒两相湍流进行了数值模拟研究 ,其中对气相场采用常用的二阶矩模型 ,对颗粒相采用了PDF模型 ,在此基础上给出了一种改进的漂移系数模型 ,用所给出的封闭模型进行了数值计算 ,并与实验结果以及未采用改进模型的PDF模拟结果进行了对比 ,结果表明改进模型能够更准确地预报颗粒脉动 。

A numerical simulation of gas-particle two-phase tu rb ulent flows in an axial symmetry suddenly expanded channel was studied. An ordin ary second order moment model was used in gas phase, a PDF model in particle pha se. A modified drift coefficient model was presented and a numerical computation was made. The result was compared with that of the experiments from an old PDF model. It is seen that the modified model can predict the particles′ fluctuatio n more correctly than the old one, and it can embody the anisotropism of particl es′motion.