叶片扩压器内三维流场数值计算与实验研究

本文采用加罚有限元方法对离心压缩机叶片扩压器内流场进行了数值分析。在数值求解过程中,为了避免流动对流占优所引起的压力场波动,控制方程离散时借鉴有限差分法的技巧,进行权函数修正,通过迎风参数来控制沿流动方向上所施加的流线迎风量,保证数值求解的稳定性。叶片扩压器内紊流流动的数值计算结果表明:在其他项的假扩散被降至最小时,压力项的震荡亦被消弱。紊流场的计算采用k-ε紊流模型。同时本文对叶片扩压器内流场进行了实验测量,通过数值计算结果与实验测量值的比较分析,结果是令人满意的。最后就提高叶片扩压器的静压效率和压缩机整机性能提出了有益的建议。 

FEM CALCULATION AND EXPERIMENTAL STUDY OF THE 3-D FLOW IN VANE DIFFUSER

The viscous incompressible turbulent flow in a vane diffuser was analyzed numerically by using penalty finite element method,based on Galerkin variational finite-element method.During discreting the controlled equations in arbitrary curvilinear coordinates,the consistent formulation of penalty pressure matrix was chosen,and conjected with the streamline upwind Petrov-Galerkin weighed residual formulation to modify the weight function.In reference to the experience of the finite difference method,the streamline upwind term only along the flow direction was controlled by the upwinding parameters.This approach ensured the stability the solution of the pressure.Numerical results of the turbulent flow in the vane diffuser were satisfactorily consistent with the experimental measurements and indicated that the spurious pressure was eliminated while the false diffusion of other terms was simultaneously minimized.