基于流声耦合的调节阀空化噪声数值预测

针对工程应用中调节阀普遍出现的空化以及由其产生的噪声问题，提出基于流声场耦合法的调节阀空化噪声数值预测方法，首先选择大涡模拟和空化模型对调节阀进行瞬态流场计算，然后联合声学边界元法利用流场信息计算噪声场特征，分别数值计算一种轴流式调节阀在空化和无空化工况时的噪声。结果表明:监测点处的声压级频率响应曲线整体趋势基本一致，计算结果符合实际规律；空化工况时的声压级频率响应曲线具有较多的峰值点，而无空化则较为平稳，可作为判断调节阀是否产生空化的依据；数值计算得到的监测点处总声压级与理论预测计算的相对误差低于7.1%，证明了数值计算的准确可行性。

Numerical Prediction and Analysis on Cavitation Noise of Control Valve Based on Fluid-Acoustic Coupling Method

As for the cavitation problem could commonly occuring in the control valve in engineering application and the noise caused by it, a method of numerical predicting the cavitation noise value in the control valve based on the fluid-acoustic coupling methodis proposed.And this method was used to numerically calculate the noise of an axial flow control valve in cavitation and no cavitation conditions, respectively.The large eddy simulation and cavitation model were selected by the fluid-acoustic coupling method to calculate the transient flow field of the control valve at first.Then the acoustic boundary element method was used to calculate the noise field characteristics by using the flow field information.The results indicate thatthe overall trend of the frequency response curve at the sound pressure level of the monitoring point is approximately the same.The sound pressure level frequency response curve in cavitation condition has more peak points. However, no cavitation is more stable, which can be used as the basis for judging whether to generate cavitation in the control valve.The relative error between the total sound pressure level at the monitoring point obtained by the numerical calculation and the theoretical prediction is less than 7.1%, it could prove the accuracy and feasibility of numerical calculations.