离心泵叶轮内部清水湍流的动态大涡模拟

提出旋转坐标下的单相液体湍流的二阶双系数动态亚格子应力大涡模拟模型并加以验证。考虑亚格子应力的对称性和量纲一致性 ,在基于应变率张量和旋转率张量的不可约量及 Smagorinsky模型和亥姆霍兹定理的基础上 ,提出亚格子应力应表示为可解的应变率张量和旋转率张量的函数。在贴体坐标系下 ,利用交错网格系统和有限体积法离散湍流控制方程 ,采用 SIMPL EC方法求解方程。水泵叶轮中湍流的流速分布规律和压力分布等计算结果都与试验结果基本吻合 ,从而证明了此模型的可行性 ,以及计算方法和程序的可靠性

Dynamic large eddy simulations of liquid turbulent flows through a centrifugal impeller

A large eddy simulation model was developed based on the Smagorinsky model. The model includes the symmetry of the subgrid scale stresses, dimensional consistency, invariants of the strain-rate tensor, and the rotation-rate tensor. The sub-grid-scale stress was modeled as a function of both the resolved strain-rate tensor and the rotation-rate tensor. The finite volume method (FVM) was used to discretize the turbulence equations on a staggered grid system. The SIMPLEC algorithm was used to solve the discretized turbulence equations. Body-fitted coordinates were used to simulate flows over complex geometry fields. The pressure and velocity distributions for the turbulent flow in the centrifugal impeller agreed well with experimental results, indicating that the model and the calculated results are reliable.