Fans and Blowers

Abstract

Gas movers with low fractional rise of pressure are discussed. These devices are fans (subsuming the term blower) and are of two types, centrifugal and axial. For both types, the principles are presented including the derivation and application of the important rules of affinity. The relation is shown between vendor specification and fan performance. The variety of fan geometries is surveyed and the interaction is examined between a fan and other process components upstream and downstream. Also reviewed are essential auxiliaries, namely fan drives, flow conditioners, noise and vibration controls, and drive seals.