在通风空调系统中 ,风机为整个系统运行提供动力。本文首先论述了风机在通风空调系统中的重要作用 ,同时从风机整体运行的角度出发 ,介绍了通风空调系统设计中风机选择时如何确定风机的出口安装角、性能曲线、比转数及应注意的问题 ,为工程设计提供了有益的建议 In ventilation and air conditioning systems, fans provide power for the entire system operation. This paper first discusses the important role of fans in ventilation and air conditioning system. At the same time, from the perspective of overall operation of fans, how to determine the outlet installation angle, performance curve, specific speed and attention should be paid when choosing the fan in the ventilation and air conditioning system design The problem provides useful suggestions for engineering design