The physical phenomena of rewetting and quenching are of prime importance in nuclear reactor safety in event of a Loss of Coolant Accident (LOCA). Generally, top spray or bottom flooding concepts are used in reactors. Numerical simulation of these processes entails the use of the concept of a rewetting velocity. However, heat transfer just before and after the rewetting front is often assumed in an ad-hoc fashion. The present work aims to evaluate the surface heat flux during rewetting and quenching process as a function of surface temperature. The experiments presented herein are primarily applicable to the bottom flooding scenario with high flooding rate. In the experiments, a rod heated above Leidenfrost point is immersed in a pool of water. The surface temperature was recorded using a surface mounted thermocouple. The surface heat flux was then determined numerically and hence can be related to a particular value of surface temperature. This type of data is useful for numerical simulations of quenching phenomena. In addition to this, high speed photography was undertaken to visualize the phenomena taking place during quenching. Both subcooled and saturated water pools have been used and compared in the experiments.
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