为研究瞬态工况下离心泵叶轮出口处的压力脉动情况,为离心泵泄漏流道流动提供边界条件,建立了包含叶轮和导叶流道的离心泵模型,基于CFD方法计算得到了其在不同工况下的性能参数,利用测试数据对结果进行了验证。分析了瞬态工况下叶轮出口处压力的变化趋势,比较了不同工况对叶轮出口压力脉动的影响,发现叶轮出口压力随叶轮旋转呈周期性变化,压力脉动频率与转速及叶轮数量有关;偏工况时叶轮出口压力脉动趋势与额定工况基本一致,但脉动频率及脉动幅值有较大区别;随离心泵转速增加,叶轮出口处压力脉动的最大值和最小值均呈减小趋势,但幅值随转速增加而增加,且增幅明显。
To study the pressure fluctuation at impeller outlet during transient process and provide boundary conditions for discharge flow in multistage pump,a three dimensional model including impeller,vane and seals was modeled.Performance parameters at various working conditions were calculated based on CFD method and compared with experiment results.Change trends of pressure fluctuation during transient process and the influence of different working conditions on the trends were analyzed.Frequencies of pressure fluctuation were found to have a close relationship with rotating speed and impeller numbers.No obvious difference was found between pressure fluctuations of different working conditions.The maximum and minimum value of pressure fluctuation at impeller outlet were both decrease with the increase of rotating speed,while the amplitude of pressure fluctuation increased with the increase of rotating speed.