ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-431-1
ISBN Online: 978-1-56700-430-4
First Thermal and Fluids Engineering Summer Conference
NUMERICAL MODEL FOR QUENCHING OF HOT SURFACE BY THE FALLING CRYOGENIC LIQUID FILM
Abstract
Contact between a liquid and solid surface, whose initial temperature exceeds the maximum value for which
a surface may be wet, is restored during quenching. Due to the complexity of the process, the mechanism of
heat transfer during quenching is still not sufficiently understood. A numerical simulation is carried out to
study the features of heat transfer and rewetting front dynamics during quenching of the vertical overheated
surface by the falling cryogenic liquid film. It was found that the initialization of the rewetting front occurs
after lowering the surface temperature to the temperature corresponding to the thermodynamic limit of a
liquid superheat. The results revealed that the maximum heat flux into the liquid during quenching is
significantly higher than those in quasi-stationary conditions. The dynamic pattern of the running fronts
obtained numerically satisfactorily correlates with the pattern observed in the copper-nitrogen quenching
experiments. The numerical model allows us to quantify the quench front velocity and temperature fields in the
heater variable in space and time. Knowledge of the quench front velocity and the full time of transition process
is required for solving the important problem of nuclear reactors safety.