Study on the methods of determining main geometric parameters of centrifugal fan impeller

Because of the complexity of internal flow characteristics of centrifugal fan, a set of wholly mature design methods of impeller theory do not exist at the present time. The paper tries to investigate and analyze the internal relations between a large number of existing aerodynamic sketches and performance parameters of centrifugal fans by means of statistical method and finds regularity. The counted and researched results show that the correspongding relations exist not only between specific speed and specific diameter but also between exit width of blade and specific speed. Based on the analysis on the selecting methods and rules of impeller´s main geometric parameters of high performance centrifugal fans, the paper improved the traditional design theory of fan and proposed some new methods, which are used to determine the main geometric parameters of centrifugal fan´s impeller.