叶轮口环间隙对离心泵性能及流动特性的影响  

Effect of wear-ring clearance on performance and flow characteristics of centrifugal pump

作　　者：高波[1] 王震[1] 杨丽[1] 杜文强[1] 李长军 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013 [2]中核集团中国中原对外工程有限公司,上海200233

出　　处：《排灌机械工程学报》2017年第1期13-17,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51576090);江苏高校优势学科建设工程项目

摘　　要：为了研究不同叶轮口环间隙对离心泵性能及其流动特性的影响,以一台单级单吸离心泵为研究对象,开展三维数值计算和试验.在传统口环间隙范围内选取2个不同的值(0.25 mm和0.50 mm)并选取一个大于常规范围的值(0.75 mm),通过对比各个间隙下离心泵的性能和前腔的流动特性,获得了前口环间隙对离心泵性能及流动特性的影响规律.结果表明:随着叶轮口环间隙的增大,离心泵扬程随之减小,效率也随之降低;口环间隙为0.50 mm时叶轮所受的径向力最大,其次是0.25 mm,0.75 mm时最小;随着口环间隙的增大,口环圆周截面的总压分布更加均匀,与前腔相接的部位总压下降,与叶轮进口相接的部位总压上升;受口环及叶轮前盖板所产生的离心力影响,前腔内流体的径向分速度随口环间隙的增大而增大,前腔轴截面的涡量也随之增大,流线的形状更加流畅规则.In order to explore the influence of different wear-ring sizes on the performance and flow characteristic, both numerical simulation and performance test are conducted in a centrifugal model pump. Two normal wear-ring clearances （0.25 mm and 0.50 mm） and an abnormal big gap （0.75 mm） are selected. By comparing the pump performance and flow characteristics at every clearance, the influence of wear-ring size on the performance and flow is obtained. It is shown that with increasing clearance both the pump head and the efficiency decrease. The radial thrust on the impeller reaches the largest at 0.50 mm gap, decreases at 0.25 mm, and eventually arrives at the smallest thrust at 0. 75 mm. The total pressure is distributed more evenly in the axial cross-section of the wear-ring at a larger clearance. The total pressure near the side chamber decreases, but that near the impeller eye increases. Because of being affected by the centrifugal force on the shroud, the radial velocity magnitmte and vorticity of the fluid in the chamber between the shroud and the casing increase gradually with increasing clearance, causing an even more smooth streamline pattern there.

关 键 词：离心泵 口环间隙 泵外特性 流动特性 

分 类 号：S277.9[农业科学—农业水土工程] TH311[农业科学—农业工程]