氢冷器回路调节阀开闭过程流场及噪声特性

为研究某核电站常规岛氢冷器回路调节阀在关闭和开启过程中的流场特性及引发的水力噪声特性，使用计算流体力学方法捕捉流场中的流动细节。通过六面体和四面体混合网格对管道和调节阀流体域进行离散，采用压力基求解器结合半隐格式求解连续性方程和动量守恒方程（N-S方程）得到压力和速度场，使用标准k-ε湍流模型对N-S方程进行封闭。阀门开闭过程由并行化用户自定义函数和动网格方法进行控制，噪声特性通过声学类比模型获得。结果表明，在调节阀的运动过程中，其内部流场具有周期性，调节阀流场水力噪声类型为典型的宽频噪声，且内部噪声水平高于调节阀下游区域约8%；调节阀整体噪声水平随开度的降低逐渐升高，且阀门内外的噪声水平差距逐渐增大。

Flow Field and Noise Characteristics of Hydrogen Cooler Circuit Regulating Valve During Opening and Closing Process

In order to study the flow and hydraulic noise characteristics of the regulating valve installed in a conventional island hydrogen cooler circuit during opening and closing process, computational fluid dynamics method is used to capture the flow details in the flow field. The hexahedral and tetrahedral mixed grids are used to discrete the flow field of pipeline and regulating valve. The pressure and velocity quantities are obtained by solving the continuity and N-S equations, the pressure-based solver and SIMPLE scheme are adopted. The standard k-ε turbulence model is applied to close the N-S equation. The opening and closing of valve is realized by parallel user defined function and dynamic mesh technology. The noise characteristics are acquired by an acoustic analog model. The results show, the internal flow field has credible periodicity. The kind of flow indicated noise of regulating valve is typical broadband noise, and the internal noise level is about 8% higher than the downstream area of the regulating valve during the dynamic process. In addition, the overall noise level of the regulating valve elevates with the decrease of the opening, meanwhile, the difference of noise intensity between inside and outside regulating valve increases gradually.