布里渊散射法流体音速测量系统的改进  

Improvement of Fluid Sound Speed Measurement System Based on Brillouin Scattering Method

作　　者：张恒飞 李欣[1] 占涛涛 何茂刚[1] 张颖[1] ZHANG Hengfei;LI Xin;ZHAN Taotao;HE Maogang;ZHANG Ying(Key Laboratory of Thermal-Fluid Science and Engineering of MOE,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学热流科学与工程教育部重点实验室,西安710049

出　　处：《工程热物理学报》2024年第2期328-333,共6页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51936009)。

摘　　要：音速是流体的一项基本热物性。布里渊散射法对于高温及超临界流体的音速测量具有优势,但与声学法相比其测量精度较低。为提高测量精度,本文从布里渊散射法音速测量的基本原理入手,分析了测量不确定度的来源,并从光路设计和探测装置两方面对现有的实验系统进行了改进,将音速的测量不确定度由1.05%降低至0.22%(k=2)。测量了正十二烷的音速并与文献数据进行对比,结果显示两者的平均相对偏差为0.22%,最大偏差为0.36%,验证了改进后实验系统的准确性和可靠性。Sound speed is one of thermophysical property of fluid.In the measurement of sound speed,Brillouin scattering method is a superior technique for high-temperature and supercritical regions.However,it is less accurate compared to acoustic methods.In order to improve measuring accuracy,this paper analyzed the uncertainty sources in sound speed measurement based on the basic principle of the Brillouin scattering method,and modifications were made to the optical path design and detecting device of our existing experimental system,resulting in the uncertainty decreasing from 1.05%to 0.22%(k=2).The sound speed of n-dodecane were then measured and compared with literature data,of which the average relative deviation and maximum deviation were reduced to 0.22%and 0.36%,respectively,validating the accuracy and reliability of the improved experimental system.

关 键 词：音速 瑞利–布里渊散射 测量系统 光路设计 

分 类 号：TK121[动力工程及工程热物理—工程热物理]