低比转速离心泵加大系数的计算方法探讨

依据离心泵叶轮出口宽度、比转速的计算式推导得出了计算低比转速离心泵流量、扬程及比转速放大系数的计算公式，提出了建立在离心泵性能预测基础上的理论计算低比转速离心泵最佳流量、扬程及比转速放大系数的方法，解决了泵行业一直依据经验统计值确定其放大系数不能使低比转速离心泵在设计点效率最高的问题．经实例验证表明：本文提出的方法能够提高低比转速离心泵在设计工况点的效率，充实了低比转速离心泵的设计理论。

Coefficient-enlargement method for design of low specific-speed centrifugal pump

On the basis of traditional formula for the outlet width of impeller and specific-speed,the formula with enlarged coefficients of the flow-rate,head and specific-speed was derived,which incarnates the relation of enlarged coefficients to the hydraulic parameters of the pump.The calculation method with enlarged coefficients for centrifugal pump based on performance prediction of centrifugal pump was proposed.The problem of pump design being unable to make sure that its efficiency is the highest when they decide the enlarged coefficients only according to experience statistics was solved.The example indicated that the method proposed here is practicable,which can enhance the efficiency of low-specific speed pump at design condition.The design theory of low specific-speed centrifugal pump was further enriched.