低磁雷诺数不可压缩磁流体湍流的非线性涡黏性k-ω封闭模型

在低磁雷诺数近似下,通过逐项模化湍动能输运方程的磁流体源项,提出一个适于任意的磁场布置形式的非线性涡黏性的磁流体湍流k-ω模型.在该模型中,使用Kenjeres-Hanjalic模型和Song的非线性涡黏性模型分别模化脉动电场-速度相关量及各向异性的雷诺正应力,并采用Wilcox低雷诺数k-ω模型对层流化进行估计.通过与直接数值模拟结果和实验结果比较,表明本文模型给出的速度型误差小于5%,摩擦阻力系数误差小于10%,能够满足工程需要.

Nonlinear eddy viscosity k-ω turbulence model for incompressible low ReM magnetohydrodynamic flows

By modelling the magnetic source term in transporting equation of turbulent kinetic energy in a term by term manner,a nonlinear-eddy-viscosity k-ω model suitable for arbitratry magnetic field orientation was proposed at low magnetohydrodynamic Reynolds number assumption.In the present model,Kenjeres-Hanjalic model and Song＇s nonlinear viscosity model were employed to close the velocity-electric field correlations and the turbulent normal stresses respectively.The relaminarization process was modeled by the low Reynolds number k-ω model meanwhile.The model was then validated with DNS and experiment results.The relative error was below 5% for the velocity profile and 10% for the friction coefficient,proving the applicability of the present model for engineering applications.