Influence of the Karman Vortex Street on the Broadband Noise Generated from a Multiblade Fan  

作　　者：Souichi SASAKI Yoshio KODAMA Hidechito HAYASHI Makoto HATAKEYAMA 

机构地区：[1]Mechanical systems engineering, Nagasaki University, 1-14 Bunkyo-machi Nagasaki City, 852-8521, Japan Doctor of Engineering,Mechanical systems engineering, Nagasaki University, 1-14 Bunkyo-machi Nagasaki City, 852-8521, Japan,Mechanical systems engineering, Nagasaki University, 1-14 Bunkyo-machi Nagasaki City, 852-8521, Japan,Products R&D Laboratory, TOTO Ltd., 2-8-1 Honson Chigasaki City, 253-8577, Japan

出　　处：《Journal of Thermal Science》2005年第3期198-205,共8页热科学学报（英文版）

摘　　要：In the prediction theory for the broadband noise generated from a multiblade fan, the vortices in the Karman vortex street was divided into n pieces. The frequency distribution of the noise was estimated so that the Strouhal number could become constant even if the wake is spread by the diffusion. From the results of the measurement of the internal flow of the fan, it was found that the noise was related to the wake characteristics of the specific location in the scroll casing where the relative flow velocity was high. The noise operating in the vicinity of the maximum efficiency point of the fan was distributed over the domain from 500 Hz to 1250 Hz. It was experimentally proved that the influence of the Karman vortex street on the noise in the domains of high and low frequencies did not exist when the distribution of the estimated sound pressure level corresponded to the measured broadband noise.

关 键 词：aerodynamic acoustic Karman vortex street turbo machinery BLADE internal flow 

分 类 号：TN911[电子电信—通信与信息系统]