ルーバー型制気口の流体音低減に関する実験および数値解析

抄録

The purpose of this study is to reduce the flow noise of a louver-type diffuser and to obtain knowledge for noise reduction design. The sound source and acoustic characteristics of the noise generated from a Louver-type diffuser were investigated by experiment and numerical analysis (CFD). The experiment was performed using an anechoic chamber capable of low-noise air supply. As a result, it was confirmed that noise such as a whistle sound was generated from the diffuser, and the peak frequency shifted to a high frequency depending on the wind velocity. Moreover, it was clarified that the cause of the whistle noise was the butting-joint and cavity of the blade. In addition, it was found by CFD analysis that closing the cavity reduces the physical quantity related to the flow disturbance such as pressure fluctuation.