涂层厚度对双吸离心泵性能及内流的影响

Effect of Coating Thickness on Performance and Internal Flow of Double Suction Centrifugal Pump

为研究涂层厚度对离心泵性能和内部流场的影响,以扬黄泵站用双吸离心泵为例,分别对叶轮和蜗壳进行涂层处理,并对不同工况下叶轮和蜗壳不同涂层厚度的组合方案进行固液两相数值计算,同时对无涂层泵进行外特性试验。研究表明,同时对叶轮、蜗壳流道进行涂层处理比仅对蜗壳流道进行涂层处理对泵的性能影响要大;对叶轮和蜗壳同时进行涂层处理后叶轮背面进口边低压区最小,不仅有利于提高泵的空化性能,还有利于减小固相颗粒对叶轮流道和蜗壳出口边的磨损,但随着涂层厚度的增加,蜗壳出口处会出现回流现象。因此,综合考虑同时对叶轮、蜗壳表面进行涂层处理且厚度为2mm为宜。研究结果为应用涂层技术提高扬黄泵站用双吸泵的抗磨蚀性能提供了依据。

To investigate the effect of coating thickness on the performance and internal flow in centrifugal pump,the present work employed a double suction centrifugal pump used in Yanghuang pumping station as the study object.The impeller and volute were coated with different thicknesses.Solid-liquid two phase flow numerical simulation was adopted to study the model pump's performance under various operating conditions.Experiment without coating was conducted to validate the simulation approach.The results show that coating both impeller and volute has more impact on the pump's performance than just coating the volute.Furthermore,it reduces the pressure on the leading edge of the blade on the suction side,contributing to improve the pump cavitation performance and decrease the eroded damage by solid particles in the impeller passage and volute outlet.However,the reverse flow would occur at the volte outlet with increasing coating thickness.Hence,it is suggested that the double suction pump would have the best performance with 2 mm thickness coating on both impeller and volute.The study underlies the ability of the coating approach to resist corrosion for double suction centrifugal pump.