外磁场调控下弹性波的反射和透射  

Reflection and Transmission of Elastic Waves Regulated by External Magnetic Field

作　　者：岳田田 李月秋[1] 王长达 YUE Tiantian;LI Yueqiu;WANG Changda(School of Science,Qiqihar University,Qiqihar 161006,Heilongjiang,China;Key Laboratory of Building Collapse Mechanism and Disaster Prevention,Institute of Disaster Prevention,China Earthquake Administration,Beijing 101601,China)

机构地区：[1]齐齐哈尔大学理学院,黑龙江齐齐哈尔161006 [2]防灾科技学院中国地震局建筑物破坏机理与防御重点实验室,北京101601

出　　处：《力学季刊》2023年第4期1012-1023,共12页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金(12072022);黑龙江省基本业务费(135509123);中央高校基本业务费(ZY20210211);廊坊市科学技术研究与发展计划(2021011037)。

摘　　要：本文应用麦克斯韦电磁学理论研究了在外磁场调控下弹性波的反射和透射问题.首先根据麦克斯韦方程组推导出洛伦兹力,其次根据运动方程推导出P波、SV波和SH波的色散关系,然后根据连续的界面条件推导出反射波和透射波相对于入射波的振幅比以及能流比.通过数值计算结果,详细分析了洛伦兹力对弹性波反射和透射的影响,结果发现,洛伦兹力不改变波动模式和色散性质,只改变弹性波的传播速度大小.最后,通过法向能量守恒验证了数值计算结果的可靠性.The reflection and transmission of elastic waves regulated by external magnetic field are studied using Maxwell's theory of electromagnetism in this paper.Firstly,the Lorentz force is derived according to Maxwell's equations,and the dispersion relation of P wave,SV wave and SH wave are derived based on the equations of motion.Then,the amplitude ratios of the reflected and transmitted waves with regards to the incident wave are calculated using the interface continuous conditions.The influence of Lorentz force on the reflection and transmission of elastic wave is discussed in details based on the numerically calculated results.It is found that the Lorentz force does not change the wave modes and dispersion properties,but only changes the propagation speed of elastic waves.Finally,the reliability of the numerical results is verified by the conservation of the normal energy flux.

关 键 词：洛伦兹力 弹性波 反射 透射 振幅比 能流比 

分 类 号：O441[理学—电磁学] O343.1[理学—物理]