[1F15-18] Molten Debris Behavior 2

[1F18] Accuracy improvement of natural circulation flow rate prediction by void fraction correlation modification

*Shusuke Yoshimura¹, Shinichi Morooka¹ (1. Waseda University, Cooperating Major in Nuclear Energy)

Keywords:Natural circulation, Void fraction

Natural circulation phenomena are applied in various instruments of nuclear power plants. The void fraction of the two-phase flow is the most important parameter in flow rate prediction. Since the flow characteristics change by flow regime, it is necessary to accurately discriminate the flow regime to predict the natural circulation flow rate. So, this study`s aim is to improve the natural circulation flow rate prediction accuracy by making the void fraction correlation formula for each flow regime. For that purpose, first, I measured the void fraction for a wide range of test conditions and confirmed the feedback to the natural circulation flow rate prediction accuracy.