一段时间以来，空气输送行业已经知道，安装在风机入口或出口附近的管道配件会对风机的性能产生不利影响。这些不利影响的程度通常通过实验室测试确定，与风机类型、管道和入口配置以及管道配件的可能组合数量相比，知识体系相对较少。本研究项目的目的是确定有限数量的各种进气装置和产品配置对典型前弯离心风机空气性能和声音的影响。

It has been known to the air moving industry for some time that duct fittings installed close to a fan’s inlet or outlet have adverse effects on the fan’s performance. The magnitude of these adverse effects is generally determined through laboratory testing, and the body of knowledge is relatively small compared to the possible number of combinations of fan types, duct and inlet configurations, and duct fittings.The purpose of this research project was to determine the effect of a limited number of various inlet installations and product configurations on the air performance and sound of a typical forward curved centrifugal fan.