定常解析を用いた液化ガス用遠心ポンプにおけるディフューザ旋回失速発生流量の簡易予測手法

抄録

The diffuser rotating stall is one of the biggest problems in pumps because unstable flow and pressure fluctuations are induced and the pump operating range is severely limited. However, it is difficult to quickly predict the flow rate at the onset of diffuser rotating stall. Unsteady-state analysis is generally used to investigate the internal flow of the pump in detail for rotating stall, but the computational cost is huge and the design process is inefficient. In this study, we investigated a simple prediction method using steady-state analysis by CFD. We focused on the deviation of the mass flow rate between diffuser passages near the onset flow rate because the precursor to the onset of rotating stall is non-axisymmetric flow. The validity of the method was verified by comparing the analysis results using the simplified prediction method with the experimental results.