Acoustic Absorption Characteristics of Perforated Thin Plate with Air Jets and Cavity

作     者：Hiromitsu Hamakawa Hiroki Matsuoka Taiki Yamai Kenta Asakura Toru Otsuru Reiji Tomiku Eru Kurihara Hidechito Hayashi Eiichi Nishida 

作者机构：Department of Mechanical Engineering Oita University Oita Japan Graduate School Master’s Program of Engineering Oita University Oita Japan Torishima Pump Mfg. Co. Ltd Takatsuki-shi Osaka Japan Department of Architecture Oita University Oita Japan Department of Mechanical Engineering Nagasaki University Nagasaki Japan Department of Mechanical Systems Engineering Shonan Institute of Technology Fujisawa-shi Kanagawa Japan 

出 版 物：《Open Journal of Fluid Dynamics》 (流体动力学（英文）)

年 卷 期：2015年第5卷第1期

页      面：1-9页

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：Acoustic Absorption Coefficient Perforated Plate Cavity Micropores Air Jets Acoustic Impedance Tube 

摘      要：The present paper focuses on the effect of air jets through a perforated thin plate on the characteristics of an acoustic absorption coefficient. We measured the flow rate, internal pressure, acoustic pressure, and transfer function by using an improved acoustic impedance tube. The normal incidence absorption coefficient was calculated from the measured transfer function using transfer function methods. As a result, the frequency characteristics of the acoustic absorption coefficient against the frequency showed a maximum value at the local frequency. The peak frequency of the acoustic absorption coefficient depended on the thickness of the background air space and the thickness of the perforated plate. As the flow rate increased through the micropores, the peak level of the acoustic absorption coefficient also increased until a flow rate of 80?l /min. As the flow rate further increased, the peak level of the acoustic absorption coefficient decreased and that of the high frequency band increased.