RESEARCH ON THE REVERBERATION ABSORPTION COEFFICIENT OF MATERIAL MEASURED BY UNDERWATER REVERBERATION FIELD METHOD
In this article, an underwater reverberation time model of a rubber board is established. Then a theory formula of reverberation time T(rm,λm) is given according to the energy relation of sound field in the reverberation chamber, rm is the reflecting fraction and km is the absorption fraction, when sound wave is injected to a rubber board, rm and λrn can be resolved base on the wave theory and boundary condition. In addition, rm and km are related to acoustic parameters of the rubber board. T(rm,λm)computed by formula and reverberation time TO measured in underwater space without material are all taken to Eyring formula, thus reverberant absorption coefficient of measured material can be forecasted. The edge effect due to the material is avoided using this method. In the simulation results of reverberation time and sound absorption coefficient agree with fact ruler. In pool experiment, reverberation time was measured in two cases. One case is that there is only water in the experimental water area, and another case is that the sample is put in water. The measurement results of the pool show the reverberant time T (rm,λm)with rubber board is shorter than the reverberant time TO without rubber board, since absorption rubber board accelerates the speed of reverberant attenuation. The reverberant time T (rm,λm) by experiment agree with the theory result. The sample frequency characteristic of the reverberation absorption coefficient accords with theory result.
Reverberation charm Underwater reverberation field Reverberation time Coefficient of absorption
Yang Song Zhen -qi Zhao Wei Zhang Sheng-qi Yu
Science and Technology on Underwater Acoustic Laboratory, Harbin Engineering University Harbin 150001, China
国际会议
深圳
英文
130-133
2011-12-09（万方平台首次上网日期，不代表论文的发表时间）