螺旋混流泵内部流动数值计算与试验预测

Numerical Calculation and Experimental Prediction of Internal Flow in Screw Mixed-flow Pump

为研究喷水推进泵在不同叶轮叶片数下的压力脉动规律,基于RNG k-ε湍流模型、SIMPLEC算法和滑移网格技术,根据叶轮动静干涉作用而引起压力脉动理论,对不同叶片数的喷水推进泵模型进行非定常数值模拟。在叶轮和导叶进出口及其内部流道设置监测点,得到压力脉动曲线。基于时域图和频域图,通过数值计算与试验验证表明:当导叶数不变时,改变叶轮叶片数对喷水推进泵内部流动产生影响进而使压力脉动幅值发生变化。在流域内,压力脉动同样受叶轮周期性旋转影响,随着叶片数的增加,压力脉动幅值反而降低;其中当叶片数为3时,导叶内部压力脉动幅值小、流动平稳。

Based on RNG k-e turbulence model,SIMPLEC algorithm and sliding mesh technology,the unsteady numerical simulation of water jet propulsion pump model with different number of blades was carried out according to the theory of pressure fluctuation caused by impeller dynamic and static interference.The pressure fluctuation curve is obtained by setting monitoring points at the inlet and outlet of impeller and guide vane and its internal flow passage.Based on time-domain and frequency-domain diagrams,numerical calculation and experimental verification show that when the number of guide vanes is unchanged,changing the number of impeller blades will affect the internal flow of water-jet propulsion pump and change the amplitude of pressure fluctuation.In the basin,the pressure fluctuation is also affected by the impeller's periodic rotation.With the increase of the number of blades,the pressure fluctuation amplitude decreases.When the number of blades is 3,the pressure fluctuation amplitude in the guide vane is small and the flow is stable.