광섬유 다중 반사 간섭을 이용한 액체의 증발 속도 센서

Abstract

In this study, an evaporation rate measurement method based on multiple reflection interference using a simple fiber optic configuration is proposed. The evaporation rate is a major factor in accident prevention and is used in various industrial, chemical, biotechnological, and biological fields. In this study, the refractive index of a liquid under an evaporation test is critical to measuring the evaporation rate. In this study, the index was measured using the Fresnel equation for reflected light. The evaporation rate sensor measures the interference signal during the evaporation of a liquid. The main frequency of an interferogram that is linearly proportional to the evaporation rate can be obtained by fast Fourier transformation of the interferogram. In our study, the evaporation rates of deionized (DI) water and ethanol were tested. Ethanol evaporated at a rate approximately four times faster than that of DI water. In addition, Hilbert transformation was used to retrieve the phase information of the interferogram over time. Our proposed method is powerful tool to monitor the evaporation of a liquid in real time. The sensor requires a tiny amount of liquid as a test sample to determine the rate of evaporation and offers high reliability and repeatability at a low cost.