摘要
由于空间结构限制,离心风机进口导管通常呈现复杂的弯曲几何构型,导致风机进口流场为显著畸变状态。为研究进口流场畸变对于风机性能的影响,针对某环卫车辆清扫系统的离心风机开展不同进口导管构型的性能与流动机理研究。首先,建立了风机数值仿真模型并采用现有机型实测性能对该模型进行验证;其次,采用ANSYS-CFX三维流场仿真软件对该风机性能进行预测,并进行详细流场分析。结果表明,进口导管构型对于风机叶轮性能具有显著影响:弯管构型导致进口相对气流角增大,风机最高效率点向小流量偏移。同时,流场分析显示,弯管进口构型在叶轮进口形成显著的周向流场畸变,使得弯管内侧流道出现大范围回流现象,进而导致叶轮效率降低。该研究为非直进口构型的风机优化设计提供了理论基础。
The inlet ducts of centrifugal fans are usually arranged in complex configurations due to space constraints, which often causes strong inlet distortions. To study the influence of an inlet distortion on the performance of centrifugal fans, a comparative study is performed for a centrifugal fan in a sanitation vehicle with different inlet duct configurations. First, the numerical simulation model of the fan is developed and validated by actual performance measurements of existing fans. Then, the ANSYS-CFX software is used to predict the flow field and the performance of the fan. Subsequently, the flow field is analyzed in detail. The results show that the configuration of the inlet duct has a significant influence on the fan performance, the elbow configuration increases the relative flow angle and the maximum efficiency point shifts to smaller flow rates. The flow field analysis also shows that the elbow inlet duct causes a flow distortion in circumferential direction at the impeller inlet and that a reverse flow is generated in flow passages of the elbow duct that cause the impeller efficiency to be decreased. This study provides a theoretical basis for an optimized design of centrifugal fans under uniform inlet conditions.
出处
《风机技术》
2017年第6期9-14,共6页
Chinese Journal of Turbomachinery
基金
上海市自然科学基金(项目号:16ZR1416900)
关键词
离心风机
进口导管
流场畸变
数值仿真
centrifugal fan, inlet duct, flow distortion, numerical simulation
