Measurement of void fraction distribution

Kureta, Masatoshi   

The Japan Society of Mechanical Engineers publishes a revised version of the technical document summarizing fluid measurement techniques. This article is part of the application section, and the main content is an introduction of application examples using advanced thermal-fluid measurement technology that is progressing remarkably. In the chapter "Void Fraction Distribution Measurement", the technology for visualizing and measuring the void fraction distribution with neutron beams for the two-phase flow of gas-liquid flowing inside the instrument is summarized. In the first half, the definition of void fraction, measurement by neutron transmission method, and basic principles of CT imaging technology were explained. In the second half, visualization and measurement results were shown in the order of two-dimensional and two-dimensional time changes of various multiphase flows, and three-dimensional and three-dimensional time changes.