Design and Optimization of H-Type Resonant Photoacoustic Cell for
Composite Buffer Cavity
JIN Hua-wei1, 2, 3, TANG Yu-hao2, SHI Jia-sheng2, FANG Lei2, LIU Wen-jian3
1. The First Affiliated Hospital of Anhui University of Science and Technology (Huainan First People's Hospital), Huainan 232001, China
2. School of Mechanical and Electrical Engineering, Anhui University of Science and Technology, Huainan 232001, China
3. Faculty of Data Science, City University of Macau, Macau 999078, China
Abstract：In photoacoustic spectroscopy detection technology, the photoacoustic cell is where the “light-heat-sound” coupling occurs. The performance of the photoacoustic cell directly affects the accuracy and sensitivity of the detection system. To improve the performance of the photoacoustic cell, a H-type resonant photoacoustic cell is simulated and analyzed based on the traditional cylindrical photoacoustic cell, and a novel H-type resonant photoacoustic cell is proposed.Through the interface of the thermal, viscous, and acoustic physical fields in COMSOL software, this paper simulated and analyzed the influence law of the height and radius of the bottom circle on the sound field in the photoacoustic cell. The results show that the sound pressure of the photoacoustic signal increases initially and then decreases with the increase in height of the platform, when other parameters remain unchanged. At the same time, the resonance frequency of the photoacoustic chamber changes significantly when the platform height is altered, and the resonance frequency initially decreases before increasing with the platform height. Similarly, when the other parameters remain unchanged, the sound pressure value of the photoacoustic signal decreases with the increase in the radius of the circle at the bottom of the circle. The resonant frequency of the photoacoustic cell changes with the variation in the radius of the bottom circle, and the resonant frequency increases with the increase in the radius of the bottom circle. The quality factors of the photoacoustic cell, before and after optimization, were 58.84 and 43.87, respectively, representing a 34.12% increase. The optimized photoacoustic signal increased by 43.15% compared to the signal before optimization. It can be seen that optimizing a single cylindrical buffer cavity into a composite buffer cavity, which combines a cylinder and a circular table, can effectively improve the quality factor of the photoacoustic cell and the photoacoustic signal. At the same time, the optimized photoacoustic cell volume is further reduced, which facilitates the miniaturization of the photoacoustic cell. This research presents a novel approach to the optimal design of traditional cylindrical photoacoustic cells.
