抄録
Characteristics of aerodynamics and noise in the centrifugal fan with inducer was investigated with respect to the two parameters: outlet angle and skew angle of the impeller. It is shown that the outlet angle considerably effects on the turbulent noise but the skew angle of the blade effects barely on that. From the view points of aerodynamics and specific noise level, the optimum value of the outlet angle is about 48 degree and that of the skew angle is about 10 degree. Moreover, we proposed a new method to calculate the width of wake which is an important parameter to controll the turbulent noise. We predicted the sound pressure level of the turbulent noise with the help of predicted width of wake and inlet relative velocity. The experimental values of the overall turbulent noise with L-weighting and A-weighting functions agreed well with predicted values.
