旋喷泵转子腔的结构优化及数值模拟计算

Structure optimization and flow numerical simulation in rotor cavity of roto-jet pump

通过改变旋喷泵转子腔的结构,结合CFD软件Fluent对不同结构的转子腔泵进行数值计算.计算时以XP300-3型旋喷泵为研究对象,基于雷诺时均N-S方程,采用标准k-ε湍流模型和SIMPLE算法.在已有的研究基础上,对转子腔结构进行优化设计,即在壁面增加凸棱、减小转子腔的轴向宽度以及2种结构叠加的综合优化设计,分析3种结构模型对泵性能的影响,再与原结构模型泵进行对比.结果表明:在同一工况下,相比于原模型,增加凸棱和适当减小转子腔的轴向宽度,都能有效减少流体在转子腔中的停留时间和过流面积,减小对泵体的磨损;两种转子腔结构对泵的扬程和效率都有明显的改善作用,尤其是对泵扬程的提高;在相同工况下,转子腔结构综合优化后,泵的理论扬程和效率较前面任何一种情况都有相当大的改善,表明在此旋喷泵转子腔的结构优化中,结构优化可叠加.

The flows in different structures of the rotor cavity in XP300-3 roto-jet pump are simulatedBy using the CFD software Fluent.The Reynolds-averaged Navier-Stokes equations,the standard k-ε turbulence model and SIMPLE algorithm are adopted in the simulations.According to the existing studies on rotor cavity structures,the cavity structure is optimizedBy using three configurations,namely adding a rib on the cavity outer surface,reducing the cavity axial width,integrating them together.The flows in the rotor-jet pumps with these configurations are simulated and their performances are extracted and compared with that for the original cavity structure.It is turned out that under the same working condition both added rib and reduced axial width are helpful to effectively reduce the residence time of fluid in the cavity and to shrink the cavity cross-section area as well as to relieve wear of pump casing.The configuration either with the rib or reduced width can improve pump head and efficiency significantly,especially for the head.For the configuration with both rib and reduced width,the pump is subject to remarked improvement in head and efficiency at the same operational condition.These results show that the rotor cavity structure can be optimized with a superposition approach.