为了找到引起管道泵振动的原因，该文研究了一比转速为59的管道泵叶轮-蜗壳的动静干涉所引起的压力脉动现象，及其对泵振动特性的影响。该文通过对比数值计算方法与试验方法获得的能量特性曲线，验证了计算模型的有效性；在此基础上分析管道泵蜗壳内的脉动压力场，通过数值计算有效研究了蜗壳周向不同位置处43个监测点在不同流量下的压力脉动幅值，特别在叶片通过频率下，蜗壳内的压力脉动特征与流量及蜗壳内监测点位置的关系。同时，通过振动试验，获取泵4个监测区域内25个监测点在不同流量下的振动幅值，通过快速傅里叶变换对振动信号进行频谱分析。计算和试验结果共同表明，隔舌区域的压力脉动幅值最大，叶片通过频率210 Hz是压力脉动的主导频率；压力脉动及泵振动均在叶片通过频率下达到最大峰值，进一步论证了叶片通过频率是管道泵产生振动的主要频率值，由该频率引起的压力脉动冲力是管道泵产生振动的主要作用力；泵的压力脉动幅值和振动幅值均高于设计工况；4个监测区域内的振动幅值从大到小依次为：管道支撑，电机，泵体，底座。研究结果可为管道泵低振动的设计提供参考。%In order to find the root causes for vibration of an in-line circulator pump, the unsteady pressure pulsation phenomenon of an in-line circulator pump with a specific speed of 59, which generated by impeller-volute RSI(Rotor-stator interaction), and its influence on pump vibration characteristics, were studied. For this study, a numerical simulation (CFD) tool was applied to get pump performance data, the CFD results were contrasted with experimental results. Once validated, the CFD model was used for simulating the unsteady pressure field existing in the volute of an in-line circulator pump. To understand more, pressure pulsation magnitudes of 43 measuring points inside the volute are obtained by means of numerical calculation, which are a function of flow rate, for several flow rates ranging from 10% to 130% of nominal flow rate. Particularly, at the blade passing frequency, the relationship among the pressure pulsation characteristics of volute, flow rates, and locations of measuring points inside the volute were successfully investigated by CFD. In addition, the vibration test was conducted to capture the vibration amplitudes as a function of flow rate, of pump by using 25 acceleration sensors which distributed inside four detecting areas. The Fast Fourier Transform (FFT) was applied for analyzing the vibration signals. The simulation and experimental results indicated that the amplitude of pressure pulsation reaches the maximum value near the tongue and blade passing frequency 210Hz which is the domain frequency contributed for pressure pulsation. Both amplitudes of pressure pulsation and pump vibration reach the peak value at the blade passing frequency. We concluded that the blade passing frequency is the domain frequency for the pump vibration, and the force of pressure pulsation, which is caused by blade passing frequency, is the main acting force for pump vibration. Simultaneously, under the off-design conditions, the magnitudes of pressure pulsation and pump vibration are higher than the design point. The sequence is 0.1Qd>1.3Qd>1.0Qd. Furthermore, the sequence of vibration amplitudes of four detecting areas is Pipe Support > Motor > Pump housing > Base. The study can be a reference for the design of low vibration in-line circulator pumps.
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