A non-equilibrium mechanistic heat transfer model for post-dryout dispersed flow regime

Based on detailed analyses of heat exchange processes arising among the droplet, the vapor phase and the heated wall, a nonequilibrium mechanistic heat transfer model for post-dryout dispersed flow regime was developed, in which six heat transfer paths were taken into account. The model has its format that is easily applied in two-fluid analysis codes. Comparisons of the present model predictions with experimental results indicated that the present model was able to accurately reproduce the wall temperature and the vapor superheat. It is also found in the study that at lower pressure and lower mass velocity conditions, the heat to be transferred by direct droplets contact to the wall and by radiation from the wall to the vapor has an important contribution to the total heat transfer and, therefore, cannot be neglected. (C) 2002 Elsevier Science Inc. All rights reserved.