去耦覆盖层降噪性能评价指标的理论探讨  

Theoretical discussion on evaluation indicators of noise reduction performance of flexible coating

作　　者：何世平[1] 何元安[2] 张文群[1] 刘桂峰[3] 闫孝伟[2] 

机构地区：[1]海军工程大学动力工程学院,武汉430033 [2]中国船舶工业集团系统工程研究院,北京100036 [3]海军工程大学训练部,武汉430033

出　　处：《声学学报》2014年第2期177-184,共8页Acta Acustica

基　　金：国家自然科学基金(11374369)资助

摘　　要：去耦覆盖层是降低水下结构声辐射的一个重要措施。为了给工程上去耦覆盖层降噪性能评价指标的选择提供理论参考,建立了点激励力作用下敷设去耦覆盖层的四端简支撑矩形板水下振动和声辐射理论模型,定义了可能表征去耦覆盖层降噪性能的五项评价指标。研究结果表明:只有振动传递损失相对独立于基板的长度、宽度和点激励力位置,而且能较好地描述去耦覆盖层隔离基板振动向水层传递的性能;而湿面均方振速插入损失较振动传递损失则能更好地反映辐射声功率插入损失,尤其在低频。作为评价指标,振动传递损失和湿面均方振速插入损失分别有各自的优点和缺点。Noise reduction by means of applying flexible coating on underwater structures is commonly used in the marine field. In order to provide theoretical references for the selection of evaluation indicators of noise reduction performance of flexible coating, a vibration and acoustics model of a simply supported underwater rectangular plate covered by flexible coating, excited by a point force, is established, and the five potential evaluation indicators are defined. Only one indicator, vibration transmission loss, is independent on the length, width of the plate and the location of point excitation force, and vibration transmission loss can describe well the performance of flexible coating to isolate the fluid from the vibration of the base plate. Another indicator, wet surface quadratic velocity insertion loss, compares better with sound radiation power insertion loss than vibration transmission loss, especially at low frequency. Thus, as evaluation indicators, vibration transmission loss and wet surface quadratic velocity insertion loss have respectively their own advantages and disadvantages.

关 键 词：性能评价指标 降噪性能 覆盖层 去耦 传递损失 插入损失 结构声辐射 板振动 

分 类 号：U666.7[交通运输工程—船舶及航道工程]