共轴式谐振管对QEPAS增益性能影响  

Influence of Coaxial Resonance Tube on Gain Performance of QEPAS

作　　者：何林峰 刘炜壕 黄逸飞 段李福 叶玮琳 郑传涛[2] He Linfeng;Liu Weihao;Huang Yifei;Duan Lifu;Ye Weilin;Zheng Chuantao(Key Laboratory of Intelligent Manufacturing Technology,Ministry of Education,College of Engineering,Shantou University,Shantou 515063,Guangdong,China;State Key Laboratory of Integrated Optoelectronics,College of Electronic Science&Engineering,Jilin University,Changchun 130012,Jilin,China)

机构地区：[1]汕头大学工学院智能制造技术教育部重点实验室,广东汕头515063 [2]吉林大学电子科学与工程学院集成光电子学国家重点联合实验室,吉林长春130012

出　　处：《光学学报》2024年第12期404-411,共8页Acta Optica Sinica

摘　　要：为提高探测性能,可通过在石英音叉周围设计声学谐振管以增强光声信号。然而,不同形状、尺寸和结构的谐振管会对音叉谐振信号产生不同程度的增强效果。旨在探究谐振管参数对石英增强光声光谱(QEPAS)探测性能的影响,通过理论建模和COMSOL Multiphysics软件仿真,研究不同参数下共轴对称和非对称结构谐振管对系统的增益性能,并进行多组对照实验。仿真及实验结果均表明,在共轴对称结构谐振管系统中,随着谐振管内径的减小,对应的最佳长度增加,相对于裸音叉系统可获得更显著的增益效果。在相同内径的谐振管条件下,相较于非对称结构,对称结构显示出更优的增益性能。仿真及实验获得的谐振管最优参数:内径为0.5 mm、长度为5.04 mm,将该谐振管作用于QEPAS探测系统,相较于裸音叉系统,该系统增益性能提高了15倍。采用该系统对体积分数为5×10^(-3)的甲烷标准气体进行长时间测量,结果显示当积分时间为72 s时,系统的探测下限为2.07×10^(-6)。Objective Trace gas detection is related to various fields in today’s world,including industrial and agricultural production,environmental monitoring,medical research,and safety protection.With the rapid development of laser technology,laser absorption spectroscopy has been widely employed in trace gas detection.Quartz-enhanced photoacoustic spectroscopy(QEPAS)based on quartz tuning fork(QTF)for detection is known for its simplicity,robust interference resistance,low cost,and quality factor.Meanwhile,resonance tubes are often coupled on both sides of the tuning to form standing sonic waves and improve the sound pressure in the QTF,which can thus enhance the tuning fork resonant for increasing the QEPAS detection performance.Although theoretical models for one-dimensional acoustic resonant tubes in co-axial QEPAS have been proposed,there remains a need for advancements in modeling,simulation techniques,and also comparative experiments to further refine the gain performance of the resonant tube in co-axial QEPAS technology.Methods A commercial QTF operating at 32 kHz(Fig.1)is utilized,and the theoretical model of QTF cantilever beam vibration is built,with the resonant coupling model between the QTF and resonant tubes proposed.Meanwhile,finite element analysis is employed to conduct a series of simulated studies to assess the gain performance of co-axial and asymmetric resonant tubes.The influence of the resonant tube parameters on gain performance is investigated,including the internal diameter,the length,and the gap between the tube and the tuning fork.To verify the simulations,we establish a QEPAS gas detection system.Initially,five resonant tubes with different parameters along with bare tuning forks are selected for experimental testing.By comparing the experimental results of these five resonant tube systems with the bare tuning fork system,the gain performance of the resonant tubes is confirmed.Subsequently,the optimized resonant tube system undergoes long-term measurement of standard methane gas with a vo

关 键 词：光谱学 光声光谱技术 石英增强光声光谱 谐振增强 优化设计 

分 类 号：TH83[机械工程—仪器科学与技术]