Void fraction correlation for rod bundle void fraction correlation based on void data of BWR fuel assembly measured by X-ray CT scanner

The purpose of this study is to develop a void fraction correlation based on the void data measured by an X-ray CT scanner. The tests were carried out in an out-of-pile test facility that can simulate the high pressure and high temperature conditions of BWRs. An electrically heated test assembly simulated a BWR fuel assembly on a full scale. The new void fraction correlation has been developed based on the drift flux model, and the prediction accuracy of the void fraction data for this study was (Δα)-bar(the average of the difference between measurement and calculation)=0.3% and σ(standard deviation of Δα)=1.9%. The agreement with other published void fraction data was fairly good. (author)