关键词: 高比转速, 离心泵, 叶片包角, 水力性能, 数值模拟

Abstract: High specific speed centrifugal pump has large flow channel. Its blade's wrap angle directly affects its hydraulic performance. Based on N-S equation and the RNG k-ε turbulence model, five pump models of different blade's wrap angle were numerically simulated under multiple conditions to study the variation trend of external characteristics, the variation laws of three-dimensional flow line and turbulent kinetic energy inside the impeller. The results showed: (1) With the increase of the angle, the highest efficiency point of centrifugal pump firstly increase and then decrease; lifting height decrease with the increase of flow rate and decrease most obviously when the angle reaches a limit value; (2) For the same flow rate, with the increase of the angle, the blade streamline become smoother, more close to the blade line type, and the total pressure of the impeller decrease; (3) in the designed condition, low-speed area mainly concentrated in flowing face of blade at impeller inlet, with the increase of the angle, turbulent kinetic energy decrease gradually; (4) Pump's hydraulic performance reaches the highest when the wrap angle is around 110 °. The research results can provide reference for the future research of high specific speed centrifugal pump.

Key words: high specific speed, centrifugal pump, blade wrap angle, hydraulic performance, numerical simulation