Calibration of a Fast Neutron Scattering Technique for Measurement of Void Fraction in Rod Bundles

Abstract

A technique based on scattering and transmission of fast neutron beams has been developed for measuring void fraction in two-phase flow through rod bundles. Experiments indicate that the scattered neutron flux varies linearly with void fraction and is largely independent of phase distribution. Measurements of the transmitted neutron flux have been used to determine phase distribution (or flow regime). The technique gives good sensitivity and count rates and appears suitable for void fraction and phase distribution measurements in transient flow boiling.