运用三维动网格技术模拟计算旋喷泵的非定常流动

运用三维动网格技术，对旋喷泵非定常流场进行数值模拟。使用Fluent流动软件的Profile文件定义旋转计算域边界面的转向和转速，将所有计算域设在同一个参考系中。采用弹簧光滑法、动态分层法及局部网格重构法三种方式实现计算域网格变形。非定常计算得到了旋喷泵的流速、压力、出口流量及转子径向力等随时间的变化结果。计算显示：在经历了一段转子启动时间后，旋喷泵出口流量趋于平稳并随时间作规则的周期脉动，脉动频率与转子的叶片数相对应；转子所受的径向力方向是由轴心指向集流管的背流一侧。旋喷泵转子所受径向力的脉动幅度较大，转子腔内液流与集流管的动静干扰现象不容忽视。本研究表明采用动网格技术可实现旋喷泵的三维非定常流场数值模拟并具有广阔的应用前景。

Numerical simulation of 3D unsteady flow in roto-jet pump by dynamic mesh technique

By using 3D Dynamic Mesh technique, the numerical simulation of the unsteady flow field in a roto-jet pump was performed in this work. The surface motion of the impeller computational domain was defined by the Profile file in Fluent commercial code, in which the rotational direction and speed of the impeller were specified. In the simulation by means of Dynamic Mesh technique, all the computational domains, as stationary, were set in an inertial reference frame. Three methods (Spring-based Smoothing, Dynamic Layering and Local Remeshing) were used to achieve mesh deformation. The time-dependent relations of velocity field, pressure, the outlet flow rate and the radial force were obtained by this unsteady simulation. After a startup stage the flow starts to exhibit time-periodic behavior corresponding to blade passing frequency of impeller. Radial force direction from the axis points to the back of the pick-up pipe. This work shows that Dynamic Mesh technique could achieve numerical simulation of three-dimensional unsteady flow field in roto-jet pump and have a strong versatility and broad application prospects.