Numerical investigation on the effect of inlet acceleration on inlet flow distortion in a centrifugal fan

Abstract

Abstract. Centrifugal fan is most widely used as an important component in ventilation system. The performance of centrifugal fan is sensitive to the inlet environment; therefore inlet flow distortion is one of the most attention problems. Numerical investigation has been carried out for the comparison of two kinds of inlet, one is standard straight duct and the other is a 90°curved duct. The results show that the distortion of inlet will seriously affect the impeller. Based on the theory of internal flow, a reasonable pressure gradient is added between the impeller and the curved duct, which is caused by inlet accelerator. Numerical simulation results show that acceleration can effectively suppress the inlet flow distortion; meanwhile it cannot affect the regular work of impeller.