用非线性k-ε-k_p两相湍流模型模拟旋流两相流动

Simulation of swirling gas-particle flows using a non-linear k-ε-k_p two-phase turbulence model

建立了两相湍流的代数应力模型 ,并由此出发 ,导出非线性k ε kp 两相湍流模型 ,目的是合理地模拟各向异性较强的旋流两相流动 ,保持二阶矩模型的优点 ,同时比二阶矩模型简单 .文中得到了气相、颗粒相的雷诺应力和两相脉动速度关联的非线性应力应变关系式。这些代数式和两相各自的湍动能k ,kp,以及两相脉动关联湍动能kpg的方程联立 ,就构成非线性k ε kp 模型 .将该模型用于模拟旋流两相流动 ,给出两相时均速度场及雷诺应力各分量 ,并且将模拟结果和实验数据以及二阶矩模型的模拟结果对照 .研究结果表明 ,该模型预报旋流两相流动的能力和二阶矩模型的能力相差不多 。

A nonlinear k ε k p two phase turbulence model is proposed for simulating anisotropic turbulent two phase flows, such as swirling flows. Non linear relationships of two phase stresses and two phase fluctuation velocity correlations with the strain rates are derived based on the two phase algebraic Reynolds stress expressions. The nonlinear k ε k p model is applied to simulate axisymmetric swirling two phase flows and the results are compared with those using the second order moment model and PDPA measurement data. The results show that the nonlinear k ε k p model is almost as good as the second order moment model but needs much less computation time.