Abstract: The flow and heat transfer characteristics in the vicinity of the quench front where quenching takes place are very complex.It is of great importance to predict the heat release in this region because that the vapor generation will influence the water distribution in the core.For the reflooding in a tight lattice,experimental results revealed that the cladding temperature drops rapidly when quench takes place,while the cladding temperature history curve was not well predicted using the existing transition boiling correlations.In this study,a new model named "transient thin liquid meniscus evaporation" is proposed to predict the heat release in the vicinity of the quench front.Through comparison with the experimental results,it is found that this new model can better predict the cladding temperature variation in the vicinity of the quench front.