直导叶几何参数对双向泵内流场及水力性能的影响

摘要

Due to convenient manufacture,straight guide vane has been widely used in axial-flow impeller machinery.With the purpose of study on the flow characteristics of the straight guide vane and its design method,a high specific speed bidirectional axial flow pump was chosen as the research object.Based on all structured grid,the SST k-ω turbulence model was used to analyze the mechanism of flow loss and the influence of straight guide vane's geometric parameters on external characteristic and internal flow field.Then design method of straight guide vane was summarized.The results show that the flow separation region expands and a large-scale backflow appears when the chord length and vane number of straight guide vane increase,the reduction of axial spacing between the guide vane and blade will increase incidence angle of vane inlet,and then increase the separation strength.Therefore,the chord length and vane number should be decreased as far as possible,and the axial spacing should be increased appropriately under the condition of allowed structure strength.The results can provide some reference for the design of straight guide vane used in the machine with axial-flow blades.%直导叶因其易于加工而广泛应用于轴流式叶片机械.为研究直导叶内的流动特性及其设计方法,以高比转速双向泵为研究对象,基于全结构化网格,采用SST k-ω湍流模型分析了加直导叶时泵内流动损失机理及直导叶几何参数对泵外特性和内流场的影响,总结了直导叶的设计方法.结果表明:直导叶弦长和叶片数增加会扩大发生流动分离的区域,形成大尺度回流;减小导叶-叶片轴向间距会增大直导叶进口冲角,加大分离强度,因此应在结构强度允许的情况下尽可能减小弦长及叶片数并适当增加轴向间距.研究结果可为轴流式叶片机械的直导叶设计提供一定参考.