WATER SPRAY INTERACTION WITH AIR-STEAM MIXTURES UNDER CONTAINMENT SPRAY CONDITIONS: COMPARISON OF HEAT AND MASS TRANSFER MODEL WITH THE TOSQAN SPRAY TESTS
Jeanne Malet, Pascal Lemaitre, Emmanuel Porcheron, Jacques Vendel (IRSN) - NURETH 11th, Avignon, France, October 2-6, 2005.
A numerical and experimental study of spray effect in a large containment vessel has been performed. The main phenomena occurring when water spray is used are the mixing induced by spray entrainment and the heat and mass transfer on droplets and walls. In order to improve the latter phenomena, different levels of model can be used. The objective of this paper is to evaluate heat and mass transfer models for the gas and the droplet phases on the basis of experimental results obtained for water spray interaction with air-steam mixtures. It is shown that the vessel depressurization (and the decrease of the connected variables, such as gas temperature and humidity) during the spray injection is lower than the one obtained with the numerical results using the gas phase model. This could be due do droplet vaporization that is not taken into account in this model. Concerning the droplet phase model, droplet temperature vertical profiles downward the nozzle are presented. It is shown that the numerical and experimental profiles are qualitatively the same, indicating a good behaviour of the droplet heat and mass transfer model.