多级冲压泵三维流场的瞬态数值模拟

Transient Numerical Simulation for Three-Dimension Flow Field in a Multistage Stamping Pump

运用CFX流动软件的滑移网格和标准的k-ε湍流模型对工业中常用的DL型多级冲压离心泵整级进行了全三维瞬态流场的数值模拟,分析泵内叶轮与导叶间的动静干扰问题。滑移网格分别设置在多级离心泵叶轮出口、固定导叶入口与泵内流体之间的交互界面,对每个时间步求解流动方程。在任一个叶轮旋转周期内,分析叶轮入口和出口的总压值出现脉动信号频率与叶轮叶片数的关系。分析了叶轮入口和出口处总压波动的幅度。该三维非稳态模拟结果为多级冲压离心泵的水力优化设计提供了依据。

By means of sliding mesh technique and standard k-εturbulent model in CFX software,numerical simulation of three-dimension transient flow field is carried out within an entire stage of a multistage stamping centrifugal pump in this work.The pressure fluctuation due to the interaction between impeller and diffuser vanes is analyzed.One of the sliding grid interfaces is set with a ring zone between impeller outlet and fluid in pump,and another is set between diffuser vane inlet and fluid in pump.Sliding mesh calculation is performed as the impeller zones slide（.i e.,rotate） relative to diffuser zone along the grid interfaces in discrete time steps.In any spatial-periodic,the total pressure on impeller inlet and impeller outlet are analyzed to obtain the relation between signal frequency and the number of impeller.The range of fluctuant total pressure on impeller inlet and outlet is analyzed.The result of simulation and analysis is to understand dynamic variation of the interior flow field and interference and finally to aim at optimal design.