基于光致瞬态光栅测量液体内的声速  

Measuring the sound speed in liquid materials by using the laser induced transient grating

作　　者：刘伟龙[1] 黄丽[1] 杨庆鑫 杨延强[1] 赵海发[1] LIU Wei-long;HUANG Li;YANG Qing-xin;YANG Yan-qiang;ZHAO Hai-fa(Department of Physics,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]哈尔滨工业大学物理系,黑龙江哈尔滨150001

出　　处：《物理实验》2018年第11期20-23,共4页Physics Experimentation

摘　　要：光束通过瞬态布拉格光栅,其衍射光的强度发生周期性变化,变化频率即为介质密度振荡的频率,由此可以测量介质中的声速.利用光致瞬态光栅测量了常温、常压条件下硝基苯和乙醇中的声速,分别为1 455m/s和1 136m/s,与文献报道结果相符.光学非接触式的声速测量方法,便于与其他装置联合使用,可用于观测高温、高压等极端条件下液体中的声速.When detecting light passed through transient Bragg grating,the intensity of the diffracted light changed periodically,and the frequency was the same as that of the medium density oscillation,thus the sound speed in the medium could be measured.The method to measure the sound speed in nitrobenzene and ethanol at room temperature and normal pressure by using the laser induced transient grating was introduced.The results were 1 455 m/s and 1 136 m/s,respectively,which were in accordance with the reported values.This optical non-contact method was convenient to be combined with other instruments,and could be used to measure the sound speed in liquid materials under high temperature and pressure.

关 键 词：光致瞬态光栅 声速 非接触式测量 液体 

分 类 号：O422.1[理学—声学] O438[理学—物理]