基于小关联时间两相湍流色噪声的近似模型及数值模拟

Small Correlation Time Colored Noise Method for Two-phase Turbulent Flows and Simulation of Wall-jet-flow

从一般高斯型色噪声模型出发,通过泛函导数,应用小关联时间,近似计算多维色噪声,得到有效Fokker-Planck方程.将其应用到两相湍流中得到颗粒相的概率密度函数输运方程,从而得到颗粒相的二阶矩模型.将颗粒应力方程简化成代数方程,建立代数应力模型.将对流扩散方程的有限分析法运用到求解两相流模型中,对壁面两相射流进行数值模拟,并将求解结果与实验结果进行对比分析.

Based on a colored noise model with general Gaussian process, by functional derivation and small correlation time expansion, high-dimensional colored noises are calculated approximately and an effective Fokker-Planck equation（FPE） is derived. The effective FPE is applied to obtain probability density function transport equations of particles in two-phase flows and a second order moment model of two-phase flows. It is simplified into an algebra stress model（ASM）. The finite analytic numerical method used in convective diffusion equation is applied to the second-order moment model. A wall-jet-flow loaded with solid particles is calculated with ASM and finite analytic numerical method. Numerical results are compared with experimental results.