计算小尺度封闭空间内混响时间的方法研究  

A New Method for Calculating Reverberation Time in Small Enclosures

作　　者：宁方立[1] 韦娟[2] 陈克安[3] 孙进才[3] 

机构地区：[1]西北工业大学机电学院,陕西西安710072 [2]西安交通大学系统工程研究所,陕西西安710049 [3]西北工业大学航海工程学院,陕西西安710072

出　　处：《西北工业大学学报》2004年第4期487-491,共5页Journal of Northwestern Polytechnical University

基　　金：国家自然科学基金 (1 9870 40 5);西北工业大学青年科技创新基金资助

摘　　要：混响时间是描述封闭声场内声音衰减快慢程度的物理量,也是音质设计中的一个重要客观评价参数。文中基于封闭空间内声有限元模型,提出了一种计算小尺度封闭空间内任意位置混响时间的方法。该方法弥补了赛宾公式不能准确求解非扩散声场内混响时间的缺陷。另外,对于尚处在设计阶段的小尺度封闭空间,由于无法通过测量获得混响时间,文中也为封闭空间内进行虚拟音质设计提供了计算混响时间的方法。给出了描述小尺度封闭空间内声场的有限元模型;在该模型的基础上推导了计算小尺度封闭空间内混响时间的方法,并编制了相应的计算机程序;在算例部分,计算了一矩形封闭空间内的混响时间,通过与实验结果进行比较,验证了这一方法的正确性。Reverberation time is a physical quantity for describing the degree of sound attenuation in enclosures, and it is also an important objective estimate parameter in sound quality design. In this paper, based on acoustical finite element method (FEM) model, a new method for calculating reverberation time in small enclosures is presented. The new method differs from Sabine′s equation in that it does not require that the small enclosures must be a diffuse sound field as Sabine′s equation does. Firstly, we review the acoustic FEM model which is established by the authors in Ref.4. Then, based on the acoustic FEM model, sound potential energy and sound kinetic energy in small enclosures are calculated. After that, the important equation for calculating reverberation time is given based on the definition of reverberation time and least squares method. Finally, we use our new method to calculate reverberation time in a rectangular enclosure; we also compare our results with those given by experiment and Sabine′s equation. The comparison shows that the new method is more effective and accurate than Sabine′s equation in calculating reverberation time of small enclosures.

关 键 词：小尺度封闭空间 混响时间 有限元法 

分 类 号：TU112[建筑科学—建筑理论]