A Study on the Measurement of the Local Void Fraction by the Optical Fibre Glass Probe : 1st Report, On the Method for the Measurement of the Local Void Fraction in a Liquid Metal Two-Phase Flow

Abstract

The local void fraction is one of the most essential parameters to clarify the precise structure of a two-phase flow. In the report, a new method is tried for the measurement of the local void fraction. The method is based on the principle that if there is a liquid metal at the top of the optical fibre glass probe, the signal light reflects and turns back the fibre glass. If not, the signal light scatters out. In the first report, the measurement is carried out in the case of a mercury-air two-phase flow in a vertical pipe. The present results show good agreement with those obtained by the method of pressure gradient.