离心风机性能相似换算误差修正算法研究

Research on the Error Correction for Similarity Design of Centrifugal Fans

相似设计在离心风机的设计和产品系列化等方面得到广泛应用。但在实际应用过程中,若模化比较大或较小时,理论计算得到的风机性能数据与产品机器的实验数据相差较大。本文对离心风机相似模化设计方法的误差产生原因进行了分析,认为气体的压缩性、雷诺数、流道表面相对粗糙度、叶轮进口密封间隙和叶片厚度等是引起误差的主要因素。针对这些影响因素,在风机内部气体流动近似相似的假设下,提出离心风机相似模化设计的修正算法。

The similarity design is widely used in the designing and serialization of centrifugal fans.In the actual application,however,it is found discrepancies in performance prediction,especially when the modeling scale is bigger or smaller.This paper analyzes the reason of causing error by similarity design of centrifugal fan.It is considered the main factors of causing error are the gas compression,Reynolds,relative roughness of flow surface,seal clearance of impeller inlet,thickness of blades and so on.Aiming at these influencing factors,a method for amending the fan modeling based on the loss mechanism under the assumption of approximate similarity of the flow between the model and designed fan is proposed.