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可能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相比，知识体系相对较小。本文所述研究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向发动机空气性能和声音的影响- 弧形离心风机。前弯风扇在供暖、通风和空调系统中很常见。引文:ASHRAE Transactions，第117卷，第2部分，魁北克省蒙特利尔

It has been known to the air moving industry for some time that duct fittings installed close to a fan's inlet or outlet can 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 combinations of fan types, duct and inlet configurations, and duct fittings. The purpose of the research described in this paper 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. Forward-curved fans are common in heating, ventilating, and air-conditioning systems.