Study on void fraction distribution of plunging jet experiment with wire mesh sensor

Abstract

The plunging jet is a phenomenon of two phase gas-liquid flow, which could be an effective method to sufficiently mix boric acid with de-ionized water, and is suitable for studying the Pressurized Thermal Shock (PTS) accident scenario of Pressurized Water Reactors(PWR). The air is entrained when the liquid jet hits the water surface, which generates bubbles during the air entrainment. This bubble entrainment has a crucial influence on the mixing process. The distribution of void fraction was studied in dependence of the jet length and flow rate. A movable three-layer Wire Mesh Sensor (WMS) is designed to measure sequences of instantaneous two-dimensional gas fractions with a high-resolution in space and time, which, from the data, derives the void fraction distributions. Comparisons of average void fraction are carried out with different jet lengths and flow rates.