ターボ形遠心送風機の小風量域における騒音低減に関する研究

（数値解析による流れ場の調査）

抄録

The noise reduction of the centrifugal blower is important problem for the working and the living enviromment. In this study, to investigate the noise in the small airflow region, we focused on the Blade-passing frequency(BPF) noise and carried out the experiment and the unsteady simulation of the flow in the blower. To clarify the cause that BPF noise occurs, we investigated the pressure fluctuation at the trailing edge of the blade and the generation mechanism. We also compared characteristics of the pressure fluctuation with those of the other airflow region. It was found that the pressure fluctuations obtained by the numerical simulation became large in the case of small and large airflow regions as well as the experimental results and the noise measurement, however the generation mechanisms of the pressure flactuation are different between the airflow regions.