离心泵泵腔液体压力分布理论计算及验证

Theoretical Computation and Verification for Fluid Static Pressure in Centrifugal Pump Side Chamber

准确描述泵腔液体压力分布是研究叶轮盖板力的核心研究问题,也是泵研究领域中的难题。建立泵腔液体流动模型并提出基本假设,将泵腔液体流动视为轴对称二维黏性层流运动,采用数量级比较法,对泵腔液体运动的Navier-Stokes方程简化,并进行积分求得Navier-Stokes方程的近似解析解,推导出设计工况下泵腔液体压力数学模型。在该数学模型计算中,引入势扬程修正系数,解决了泵腔入口液体压力的计算问题,并给出具体确定方法。以IS80-50-315型离心泵为研究对象,在不同叶轮平衡孔直径下,对设计工况下前后泵腔液体压力进行测试和理论计算,对比分析结果表明,两者结果较为一致。还采用2个典型的泵腔液体压力测试实例,进一步验证了设计工况下泵腔液体压力数学模型的可靠性。该研究成果是对经典泵腔液体压力计算公式的补充与完善。

The accurate description of fluid pressure distribution in pump side chamber is the core research problem for the study of impeller shroud force and also is a problem in the research field of pump.The fluid flow model of pump side chamber is built and some assumptions are made.Based on which,the fluid flow can be regarded as a two-dimension axial-symmetric viscous laminar flow.By comparing orders of magnitude,the Navier-Stokes equations for fluid flow in pump side chamber are simplified.Then they are integrated to obtain the analytical solutions.Therefore,the mathematical model of fluid pressure is obtained on the design condition.The correction coefficient of potential head is introduced to the model,which solves the problem of the calculation for liquid pressure in pump side chamber inlet.And the determination method of which is also provided.The IS80-50-315 type centrifugal pump is taken as the research object.The fluid pressure in pump side chambers is tested and theoretical calculated with different balance-hole radius.The analysis result shows that the theoretical curves agree well with the experimental ones.In addition,the reliability of the mathematical model of fluid pressure is also further verified by two typical test cases.The research is the supplement and perfection for the classical calculation method of fluid pressure in pump side chamber.