离心风机的内部流场数值模拟及噪声预估

建立后向板型叶片离心风机的流场模型，运用非结构化网格对流场模型进行网格划分，流场模拟的湍流模型采用标准k-ε模型，风机旋转区与非旋转区的耦合采用移动参考坐标系模型MRF，利用Fluent流体分析软件对离心风机的三维流场进行模拟仿真，得出叶轮、蜗壳的速度、压力等分布云图，在此基础上，运用数值计算方法对所研究的离心风机进行噪声预算，结果表明：考虑蜗壳与叶轮之间的区域计算所得流场更加符合实际工况；叶轮对气流做功，叶片根部气体的速度最小，叶片边缘处速度最大；蜗壳内侧的静压与全压均偏低；蜗壳的静压与动压在蜗舌区域均发生突变。研究结果有助于了解风机内部流场的运动规律，为风机结构优化及噪声优化研究提供参考。

Numerical simulation of inside flow field and noise forecast for the centrifugal fan

The flow model of centrifugal fan with backward plate-shaped leaves is established,the flow model is meshed with unstructured grid,the standard k-εmodel is used for the flow field simulation,the moving refer-ence coordinate system MRF model is used for the coupling of rotating and non-rotating zone area,the fluid anal-ysis software Fluent is used to make the three-dimensional flow field simulation for the centrifugal fan,and the speed and pressure contours of impeller and volute are obtained.On this basis,numerical methods are used to make the noise budget for the centrifugal fan.The results show that the calculated flow field is in line with the actual working conditions considering the area between the volute and impeller.The impeller does work on the airflow,the velocity of the air at the root of blade reaches the minimum,and the velocity of the flow at leaf edge is the maximum.The static and total pressures of the inside of the volute are low,and the static and dynamic pressure in the tongue region has a abrupt change.The results of the simulation analysis are helpful to understand the movement laws of the flow field inside the fan,and provide references for the optimization of structure and noise.