用于痕量H_(2)S检测的音叉设计及性能分析  

Design and performance analysis of tuning fork for trace H_(2)S detection

作　　者：李冰心 刘硕 李瑶 赵赛丽 LI Bingxin;LIU Shuo;LI Yao;ZHAO Saili(School of Electronics and Information Engineering,Hebei University of Technology,Tianjin 300401,China;School of Electrical and Information Engineering,Zhengzhou University,Zhengzhou,Henan 450001,China)

机构地区：[1]河北工业大学电子信息工程学院,天津300401 [2]郑州大学电气与信息工程学院,河南郑州450001

出　　处：《河北工业大学学报》2024年第5期47-58,共12页Journal of Hebei University of Technology

基　　金：河北省教育厅科学研究项目(CXY2024032);国家自然科学基金资助项目(62475067);河北省自然科学基金(津京冀合作专项)资助项目(F2024202116)。

摘　　要：针对商用标准石英音叉在石英增强光声光谱(Quartz-Enhanced Photoacoustic Spectroscopy,QEPAS)应用的局限性,对声波探测器石英音叉的前6阶振动模态进行了仿真研究,通过优化石英音叉参数,分析各参数对共振频率的影响,设计了一种低共振频率且高品质因数的新型石英音叉。经过测试,该音叉共振频率为12.21 kHz,品质因数高达12068,叉指间隙为0.40 mm,与商用30.72 kHz的标准石英音叉相比,共振频率降低60.25%,叉指间隙提高2倍,能量积累时间提高1.95倍。通过优化耦合共振管长度及光源的激励位置,提高了系统的探测性能。利用波长调制和二次谐波解调技术,得到系统的二次谐波信号与H_(2)S浓度存在良好的线性关系,基于QEPAS技术探测的检测限低至186×10^(-9),实现了H_(2)S的高灵敏度探测。In response to the limitations of commercial standard quartz tuning forks in the application of Quartz Enhanced Photoacoustic Spectroscopy(QEPAS),a simulation study was conducted on the first six vibration modes of quartz tuning forks which was an acoustic detector.By optimizing the parameters of quartz tuning forks,the influence of each parameter on resonance frequency was analyzed,and a new type of quartz tuning fork with low resonance frequency and high quality factor was designed.After testing,the resonance frequency of the tuning fork is 12.21 kHz,with a quality factor of up to 12068,and a fork clearance of 0.40 mm.Compared with the commercial standard quartz tuning fork of 30.72 kHz,the resonance frequency is reduced by 60.25%,the fork clearance is increased by a factor of 2 times,and the energy accumulation time is increased by a factor of 1.95 times.By optimizing the length of the coupled resonant tube and the excitation position of the light source,the detection performance of the system has been improved.By using wavelength modulation and second harmonic demodulation techniques,a good linear relationship between the second harmonic signal of the system and H_(2)S concentration was obtained.Based on QEPAS technology,the detection limit was as low as 186×10^(-9),achieving high sensitivity detection of H_(2)S.

关 键 词：石英音叉 石英增强光声光谱 H_(2)S检测 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] X831[自动化与计算机技术—控制科学与工程]