无过载超低比转速离心泵水力设计

Hydraulic Design of Non-Overload,Super-Low Specific Speed Centrifugal Pump

在比转速n_s<30时通常不再设计成离心泵,因为泵效率较低,轴功率曲线太陡极易产生过载现象,笔者首次较详细地研究超低比转速离心泵的无过载设计方法,针对n_s=23微型离心泵,给出叶轮主要几何参数D_2、b_2、β_2、Z、φ的选取原则和叶片平面流道的绘型。文中还给出测试结果和性能曲线。研究表明;只要设计合理,n_s<30时完全可以设计成效率较高的无过载离心泵。

For specific speed ns<30, the pump is generally not designed in centrifugal type due to low pump efficiency and steep brake power curve which results in overload easily. For the first time in the field, the authors study the non-overload design method for super-low specific speed centrifugal pump. With ns = 23 miniature pump as an example, the selection principles of main impeller geometrical parameters such as impeller diameter D2 , exit width b2, discharge angle β2, vane number Z and vane rapping angle ψ are discussed. The drawing method of plane flow passage is also given. The test results and performance characteristics are introduced. The study shows that with reasonable design, the pump with ns<30 can be developed with higher efficiency and non-overload characteristics.