Study on Influence of Radian and Longitudinal Offset of Worm Tongue on Fan Noise

摘要

Flow field inside multi-blade centrifugal fan is calculated by Three-Dimensional Numerical Simulation, and the results showed that the backflow area close to front disc below the worm tongue is an important factor for influencing fan noise. Aiming at this area, changing radian and longitudinal offset of worm tongue is used to reduce the range of backflow area. And then many conditions of various radians and longitudinal offsets of worm tongue are calculated in order to analysis influence of radian and longitudinal offset of worm tongue on fan noise.