Theoretical Prediction of Pressure Fluctuations in a Diffuser Pump based on Rotor-Stator Interaction Analysis

采用标准k-e湍流模型，求解了扩散泵全级内二维和三维非定常reynolds -average navier-Stokes （RANS）方程，研究了叶轮与扩散叶片相互作用引起的压力波动。在不近似叶轮与扩压器叶片数比的情况下，采用任意滑动网格完全解决了部件间相互作用引起的瞬态流动问题。此外，将二维涡量法应用于扩散泵全级。将非定常数值计算结果与奇异法计算结果及实验数据进行了比较。本文的研究结果表明，结合k-e模型和涡量法的Navier-Stokes代码能够预测扩散器内的压力波动。此外，广泛的数值研究确定了导致扩散器压力波动的来源，并有助于理解扩散泵中叶轮-扩散器相互作用的机制。

Two-dimensional and three-dimensional, unsteady Reynolds-averaged navier-Stokes (RANS) equations with standard k-e turbulence models were solved within a whole stage of a diffuser pump to investigate pressure fluctuations due to interaction between impeller and diffuser vanes. The arbitrary sliding mesh was employed for the full solution of transient flow due to the interaction between components without approximating the blade count ratio of impeller to diffuser. In addition, two-dimensional vorticity method was applied to the whole stage of diffuser pump. The unsteady numerical results were compared with ones calculated by singularity method and experimental data. As a result of the present study, the Navier-Stokes code with the k-e model as well as vorticity method is found to be capable of predicting pressure fluctuations in the diffuser. Further, extensive numerical studies identified sources contributing to the pressure fluctuations in the diffuser, and help understand the mechanism of impeller-diffuser interactions in the diffuser pump.