EVAPORATION OF VOLATILE LIQUID POOLS UNDER FORCED CONVECTION: EXPERIMENTAL APPROACH FOR MULTI-COMPONENT LIQUIDS AND VALIDATION OF A VAPORIZATION MODEL

ABSTRACT The evaporation of pools of volatile liquids under dynamic conditions is gaining interest as an engineering subject. Indeed there is an increasing need to optimize the control of thermal or chemical processes and to cope with more and more stringent Environmental, Health and Safety (EHS) regulations applicable to the handling of hazardous liquids, especially those relating to stationary gas turbine installations. A specific issue, tied with flammable substances, comes from the fact that the transition from a flame to an explosion is not sufficiently well controlled due to the difficulty in modeling complex installations. Therefore, the current approach used to address explosion risks consists in quantifying the flux of vapors emitted by the pool and evaluating the mechanical effect entailed by a potential ignition of the flammable cloud generated. It is therefore of paramount importance to accurately know, under variable vaporizing conditions, how much of the volatile matter is extracted by the ventilation stream from the liquid pool and how these vapors get diluted downstream of the source. A survey of the literature shows that while pool evaporation of water has been extensively covered by experimentation, most organic liquids including hydrocarbons, alcohols, ethers, etc. have been insufficiently studied. In order to fill this gap, the authors have combined an experimental approach enabling to quantify the source of vapors with a dedicated Computational Fluid Dynamics (CFD) approach describing the 1 mixing/dilution phenomena in the gas phase. This dual approach has proved very fruitful as it leads to realistic spatial distributions of the species downstream of the source. Therefore it has been utilized to develop experimentally 1 Dominique.alonso@ensic.inpl-nancy.fr verified data for the evaporation rate of single and multicomponent liquids. This paper presents the original experimental rig developed to quantify the vaporization rates. The elaboration of the CFD model and the results obtained when coupling both approaches will be the matter of a next paper