Study on Analytical Prediction of Forced Convective CHF in the Wide Range of Quality

For the purpose of predicting CHF for a wide range in quality, we developed the analytical CHF prediction method. Two-phase flow analysis code based on multi-fluid model was developed and, by using typical dryout model and DNB model, CHF predictions for a wide range in quality were carried out, firstly. The dryout model and DNB model gave good predictions for high quality conditions and low quality conditions respectively. The boundary between high quality and low quality seemed to be about 0.1 to 0.2, which corresponds to the annular mist flow transition criterion. Based on this result, secondly, we carried out CHF predictions by using dryout model or DNB model selectively depending on the flow regime and got agreement to some extent with CHF data for a wide range in quality.