转速对贯流泵装置流道水力参数影响的数值分析

为了研究贯流泵装置进出水流道水力性能受转速的影响规律,以贯流泵装置为研究对象进行全流道的数值计算,通过将能量性能数值预测结果与物理模型试验结果对比,验证了数值模拟结果的有效性。在考虑水泵与进出水流道内流相互影响条件下定量分析转速对进出水流道水力性能参数的影响规律。结果表明:(a)不同转速时进水流道水力损失比与流量系数的关系曲线变化趋势基本相同。相同转速时,随着流量系数的增大,进水流道水力效率逐渐减小,流道出口环量先减小、后增大;相同流量系数时,进水流道出口面的平均环量随转速的增加而增加。(b)不同转速时,随着流量系数的增大,出水流道进口入流涡角相对值先减小、后增大。在相同流量系数时,随着转速的增加,出水流道的静圧比逐渐增加,出水流道进口面的偏流角分布基本相同。

Numerical analysis of the effect of rotational speed on the hydraulic parameters for flow conduits of shaft extension tubular pumping system

In order to investigate the effect of rotational speed on the hydraulic performance of inlet and outlet conduits for S-shaped shaft extension tubular pumping system, three dimensional and steady turbulent flow in the pumping system was simulated by the computational fluid dynamics technology. Then, the CFD results are compared with the experiment results to validate the application of numerical analysis. The hydraulic performance parameters of inlet and outlet conduits were quantitatively analyzed considering the hydraulic interaction of conduits and impeller. Results indicated that the change trend of relationship curves between hydraulic loss ratio and flow rate coefficient is same in different rotational speed. With the increase of flow rate coefficient, the hydraulic loss ratio gradually increases, the hydraulic efficiency increases firstly then decreases gradually, and the average velocity circulation of outlet section firstly increases then decreases gradually under the same rotational speed. Meanwhile, with the increase of rotational speed, the average velocity circulation gradually increases under the same flow rate coefficient. In addition, the relative swirl angle decreases firstly, then increases with the increase of flow rate coefficient under different rotational speed. It could also be concluded that with the increase of rotational speed, the static pressure ratio of outlet conduit increases gradually and the distribution of drift angle in inlet section of outlet conduit is same. There is no linear functional relationship between square of hydraulic loss and flow rate for outlet conduit.