Acoustic resonant hydrogen leak detection for hydrogen production by water electrolysis

Abstract

A non-invasive hydrogen leak sensor based on acoustic resonant frequency measurement using the fast Fourier transform is developed. The sensitivity of the resonant frequency to hydrogen concentration variation of the acoustic resonator is utilized. The acoustic resonator has been optimized through finite element method analysis to meet the requirements of the measurement application. Under the premise of fully considering the frequency response, detection time, and related metrological characteristics, the excitation and detection circuit based on a STM32 microprocessor was designed. To reduce the influence of temperature on measurement results, a double resonator structure is adopted. The overall sensor design is made up of low-cost, simplicity, and commercially available components. The experimental results show that the sensitivity limit is 33.6 ppm and an upper dynamic range of 100%. The presence of hydrogen can be quickly detected within 5 s. It can fulfill the requirements for detecting high concentration hydrogen leakage and provide monitoring data for the safe operation of the hydrogen production system.