基于轴承简化模型后口环间隙对泵性能的影响

摘要

As for the complex rear wear-ring return-flow system,a method is proposed to simplify bearing model.The method was applied and based on the simplified model,the flowing of three-dimensional turbulent in a high-speed pump (38500r/min) was computed by using the time-averaged Navier-Stokes equation and the SIMPLEC algorithm.The result shows that this method is feasible in engineering practice.On this basic,the models with different rear wear-ring clearance were simulated.The external characteristic and the fluid flow of the pump under all circumstances were analyzed.Research shows that the rear wear-ring influences the external characteristic of the pump obviously.The leakage of rear wear-ring is great influenced by the size of wear-ring,and is roughly linear relationship with the clearance size.The increase of clearance of rear wear-ring can improve the flow state in rear cavity and decrease the vortex region,and smooth the flow.%针对本文模型复杂的后口环回流系统,提出一种轴承模型简化方法.基于SIMPLEC算法,采用雷诺时均Navier-Stokes方程和RNG k-ε湍流模型,对采用轴承简化模型的一台高速泵(38 500 r/min)进行全流场三维湍流数值模拟,对比试验数据,证明该方法在工程实际中具有可行性.在上述基础上,对不同后口环间隙的模型进行模拟,分析各种情况下泵的外特性及内部流动变化,结果表明后口环间隙变化对泵的外特性影响明显,后口环泄漏量受口环间隙尺寸的影响较大,与口环间隙尺寸大致呈线性变化.研究还发现后口环间隙的增大对后泵腔内的流动状况有着改善作用,使后泵腔内的漩涡区减小,流动更为顺畅.