摘要
应用高雷诺数ｋ－ε湍流模型进行了混流式风机叶轮内三维流动的计算研究．使用ＳＩＭＰＬＥ型算法求解了全三维雷诺平均质量加权Ｎ－Ｓ方程．对流项采用了高阶精度的上流加权近似和ＴＶＤ类型的ＭＵＳＣＬ差分格式．采用非正交贴体坐标和同位网格系，速度的协变物理分量被选作为独立求解变量．为了消除非物理的压力和速度振荡，对界面上的逆变速度分量采用Ｒｈｉｅ、Ｃｈｏｗ动量插值方法．离散方程以能够使用三对角矩阵算法的形式书写，并用ＡＤＩ方法求解．求解中考虑了周期边界条件和运动壁面边界条件．文中给出了２个混流叶轮的计算结果．１号叶轮采用常规的设计方法进行设计．２号叶轮采用新型的弯扭组合三元叶轮设计方法进行设计，以消除和抑制叶轮叶道内和叶轮后无叶间隙处的气流分离和旋涡．计算结果表明，全三维湍流计算能有效地预测混流叶轮叶道内及无叶间隙处的分离，以便改进气动设计、几何设计，提高混流式风机的性能．
The complex three dimensional flow field in an mixed flow impeller incorporating high Reynolds number k ε turbulence model is studied. The fully three dimensional Reynolds averaged Navier Stokes equations are solved. A computational procedure has been developed for prediction three dimensional incompressible separated turbulent flows in the impeller. The SIMPLE like algorithm is used. Convective terms are approximated with higher order upstream weighed approximations and a TVD type MUSCL scheme. Physical covariant velocity components are selected as dependent variables. The non orthogonal boundary fitted coordinates system and collocated grid arrangement are also employed. Rhie and Chows momentum interpolation method is adopted to eliminate the non physical pressure and velocity oscillations. Periodic boundary condition and moving wall boundary condition are considered to simulate truthfully the turbulent flow field in impeller. Two mixed flow impellers are computed. The first one is designed by conventional method and the other is a improved design which have been considered with eliminating flow separation and viscous vortex in the first design. The computed results show that fully three dimensional turbulent flows computation can efficiently predict three dimensional separated flows and viscous vortex in mixed flow impeller and vaneless clearance.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
1996年第10期55-63,共9页
Journal of Xi'an Jiaotong University
关键词
混流式
鼓风机
湍流
三维流动
mixed fan three dimensional turbulent flow SIMPLE like algorithm
