自由边界矩形薄板弯曲振动辐射声场指向性研究  

Study on directivity pattern of acoustic field radiated by rectangular plate with flexural vibration under free boundary conditions

作　　者：张勇[1] 贺西平[1] 李伟[1] 许龙[1] 

机构地区：[1]陕西师范大学应用声学研究所,陕西西安710062

出　　处：《陕西师范大学学报（自然科学版）》2010年第4期36-39,45,共5页Journal of Shaanxi Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(10874107);陕西省自然科学基金资助项目(2007A07)

摘　　要：应用有限元法,求出了声源表面振动位移.对瑞利积分公式进行离散,推导出了矩形薄板指向性的数值表达式,并以自由边界弯曲振动矩形薄板为例,计算了其二维及三维指向性.结果表明:对于自由边界弯曲振动矩形板的不同振动阶次,其在中心轴线上无指向性.随着矩形板振动阶次的增加,指向性趋向尖锐.The surface vibration displacement of the sound source is obtained by the finite element method.The directivity pattern of a rectangular thin plate with flexural vibration under the free boundary condition is derived through dispersing the Rayleigh′s integral formula.Based on the above,the directivity patterns in both 2-dimension and 3-dimension are calculated.The results showed that when the vibrational order of the rectangular thin plate in flexural is increased,the distribution of the directivity pattern becomes more acute,but there is no directivity pattern in the axis.

关 键 词：指向性 弯曲振动 辐射声场 有限元方法 

分 类 号：O426.1[理学—声学] TB532[理学—物理]