Name : [in Japanese]
Date : July 07, 2022 - July 08, 2022
A perforated metal plate has many small holes. High-speed air flow across the perforated metal plate generates noises caused by aerodynamic vibration or plate vibration. This study deals with mechanism of generation noises from the high-speed air flow through the perforated metal plate. Expansion type perforated metal plate with 7 holes generated large noise with a prominent peak. In the experiment, to consider the mechanism of prominent peak noise generation, flow visualization and measuring velocity fluctuation of jet flow are performed. The noise source was recognized by measuring COP values of velocity fluctuation of jets. Jet flow interference was found by flow visualization method. Jet flow interference is important for the prominent peak noise generation.
