弱散射材料中激光超声单散射理论模型  

Theoretical Model of Singly-Scattered Laser-Induced Ultrasound in Weak-Scattering Materials

作　　者：许伯强[1] 杨小平[2] 徐桂东[1] 徐晨光[1] 陈安麒[1] 刘洪凯[2] 

机构地区：[1]江苏大学理学院,江苏镇江212013 [2]江苏大学机械工程学院,江苏镇江212013

出　　处：《中国激光》2012年第3期63-67,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金面上项目(11172114);国家863计划(2009AA03Z107);江苏省高校自然科学研究重大项目(10KJA140006)资助课题

摘　　要：基于扩散波传输理论,针对弱散射介质中的激光超声散射,提出单散射假设,建立包含信号源、超声散射和接收信号的理论模型。理论分析结果表明横波和纵波的散射机理相同,得到了横波和纵波的单散射强度在时间域的分布规律。进而分析统计平均深度和衰减系数对单散射强度的影响。为材料的无损检测、材料微观结构的分析及性能评价提供理论依据。Based on the diffuse wave transfer theory,a theoretical model of singly-scattered laser-induced ultrasound in time domain which contains signal source,scattering and received field is developed under the assumption of singe-scattering.Theoretical results indicate that transversal and longitudinal wave have the common scattering mechanism and the singly-scattered intensity distribution of transversal and longitudinal wave in time regime are got.Furthermore,statistical average depth and attenuation coefficient are discussed for their influence on intensity distribution.The model has given theoretical description for non-destructive evaluation and micro-structural analysis of materials.

关 键 词：散射 理论模型 强度分布 统计平均深度 衰减系数 

分 类 号：TN249[电子电信—物理电子学] O426.2[理学—声学]