초음파 수위계의 최소 탐지거리 단축을 위한 파동유도관

Abstract

This paper describes a method to shorten the minimum detectable distance of an ultrasonic sensor in a liquid-level meter. The minimum detectable distance, which is limited by the number of ultrasonic transmission pulses and the ringing of the vibration plates in the sensor, needs to be shortened by an appropriate method. The purpose of this research is to improve the proximal measurement capability by combining the ultrasonic sensor for a liquid-level meter with a waveguide. Flat- and wedged-wall-type waveguides were designed and finite-element analysis was performed for ultrasound transmission and reception. Experiments were conducted for the distance and water level measurements by using the ultrasonic sensor combined with a waveguide. The results of the finite-element analysis and experiments showed that the wedged-wall-type waveguide produced reasonable measurements of the distance in the proximal range. We confirmed the improvement of the proximal-measurement capability of an ultrasonic level meter, thus shortening the minimum detectable distance by combination with a waveguide.