轴伸贯流泵压力脉动特性及其改善方法

Pressure pulsation characteristics and improvement methods of axial extension tubular pump

为研究轴伸贯流泵压力脉动特性及其改善方法,应用计算流体动力学数值方法,采用在出水流道内增设导流板的方式进行贯流泵优化设计,并结合真机试验验证了数值计算方法的正确性.研究结果表明:在小流量工况下,原模型与优化模型泵的压力脉动时域特性和频域特性较额定工况下要差,但不同流量工况下叶轮进口处压力脉动特性均受到旋转叶轮显著影响;小流量工况下压力脉动变化强烈,原模型在叶轮出口及后导出口处的压力脉动低频成分明显,增设导流板可有效降低这2处的压力脉动变化幅值及其低频成分;在额定工况下,贯流泵压力脉动周期性规律显著,导流板则能有效降低前导进口及叶轮进口处的压力脉动变化幅值及其低频成分;在不同流量工况下,出水流道内导流板消涡效果均十分显著.

In order to study the pressure pulsation characteristics of the axial extension tubular pump and its improvement methods,the CFD numerical simulation was applied to optimize the design of tubular pump by adding a deflector in the outlet channel,and the correctness of the numerical calculation method was verified by real machine test.The results show that the pressure pulsation and frequency domain characteristics of the original model and the optimized model pump under small flow conditions are worse than those under the rated conditions,but the pressure pulsation characteristics at the impeller inlet under different flow conditions are significantly affected by the rotating impeller.The pressure pulsation changes strongly under small flow conditions.The low-frequency components of the pressure pulsation at the impeller outlet and the rear guide vane outlet of the original model are obvious.The addition of a deflector can effectively reduce the variation pressure pulsation amplitude and low-frequency components at these two places.Under rated conditions,the periodic law of pressure pulsation is significant,and the deflector can effectively reduce the pressure pulsation amplitude and low-frequency components at the front guide vane inlet and the impeller inlet.Under different flow conditions,the vortex elimination affected by the deflector in the outlet flow channel is very significant.