ABSTRACT
Throughout industry, the need to move large quantities of air or convey products is ever present. To meet the air- and product-handling requirements, a variety of fans and blowers is most often employed. It is rare not to find one or more fans or blowers in each department of an industrial or manufacturing complex. In many ways fans and blower noise is one of the easiest and most straightforward acoustical problems to solve. This chapter develops a systematic approach to controlling fan and blower noise. Fans will be considered first, followed by blowers. In this text, blowers will refer to the high-pressure rotary positive displacement type which can better be described as compressors. There are two basic types of centrifugal fans, backward or forward curved and radial. There are numerous types designed for a wide variety of applications; however, they usually can be considered variations and/or combinations of these basic types.
