Measurement of Circumferential Liquid Film Thickness in Horizontal Gas-Liquid Annular Flow Using Ultrasound

Circumferential liquid film thickness (CLFT) is an important characteristic parameter of gas-liquid two-phase annular flow, and its measurement technology and method has always been a research focus of two-phase flow. In this paper, a set of circumferential liquid film thickness sensor measurement system is designed based on ultrasonic technology, and the non-contact measurement of circumferential liquid film thickness of horizontal pipe is realized by using ultrasonic echo reference signal elimination (UERE) method. The experimental pipe diameter is 50 mm, the ranges of gas and liquid superficial velocity are 15-30 m/s and 0.015-0.1 m/s, respectively. The working condition is ambient temperature, and the pressure P is 0.1-0.7 MPa. Besides, the liquid film thickness at different circumferential positions is obtained and analyzed quantitatively under 53 working conditions. The experimental results are compared with the existing correlation, and considering the influence of system pressure, a new prediction correlation for CLFT is established. The relative error between the experimental results and the new correlation is within ±25^%, which verifies the applicability of the new correlation.