洗扫车专用风机数值模拟与内流特性分析

针对洗扫车专用风机内流场强旋转和强曲率特点，提出了适宜于分析强旋转和强曲率效应的湍流新模型，并继而建立了针对洗扫车专用风机的CFD数值模拟策略。研究结果表明：专用风机内流呈现复杂的强旋转效应，该效应下叶轮间隙流易造成严重的能量损失，叶轮间隙尺寸是专用风机气动设计的关键要素；专用风机叶轮在强曲率、强旋转效应的作用下，小流量工况时更易出现大面积流动分离甚至回流；不同流量下，回转面静压和总压均呈现出非对称性。随着流量的增加，静压、总压分布的非对称性会逐渐减弱。分析结果对于提高专用风机的性能，改进其气动特性提供了理论支持，更好地为生产实践提供指导。

Numerical Simulation and Analysis of Internal Flow Characteristics for Centrifugal Fan of Sweepers

For the strong rotation and curvature effects of flow field of the sweeper centrifugal fan, a new turbulencemodel and CFD numerical strategy for the analysis of the sweeper centrifugal fan was put forward. The results show thatstrong rotation effect was observed in the internal flow of the sweeper centrifugal fan. Under this effect. the clearanceflow of the centrifugal impeller led to heavy energy loss. Therefore. the clearance size between the impeller and the inletcollector is the key point for the aerodynamic design of the sweeper centrifugal fan. When the operating point was locatedon the range of the low flowrate. separated flow. even circumfluence, appears more easily than that of the otheroperating points because of strong rotation and curvature effects. Under the different operating flowrates. the distributionof static and total pressure on the revolution plane is unsymmetrical. With the increase of the flowrate. the asymmetricaldistribution of static and total pressure becomes weak gradually. The analysis results strongly provids a theoreticalsupport to improve the aerodynamic performance of the sweeper centrifugal fan. as well as a guidance to productionpractice .