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Downlosources, and may attain a critical state before it is ‘‘atomized.’’ The gas turbine combustors used in propulsion applications are being designed to operate at increasingly higher pressures, which may exceed the critical pressure of the fuel. The modeling of transcritical droplet vaporization also represents a scientifically challenging problem, since the conventional ‘‘low-pressure’ ’ drop-let models are generally not valid at high-pressure conditions. For example, the gas-phase nonidealities and the liquid-phase solubil-ity of gases are negligible at low pressures, but become essential considerations at high pressures. Consequently, a single-component fuel droplet would assume a multicomponent behav-ior, and liquid mass transport in the droplet interior would become an important process. Secondly, as the droplet surface approaches the transcritical state, the latent heat reduces to zero, and the gas and liquid densities become equal at the droplet surface. Then, transient effects in the gas phase would become as important as those in the liquid phase, since the characteristic times for trans-port processes in the two phases become comparable. In addition, the liquid and gas-phase thermophysical properties become pressure-dependent. Also, under convective conditions, the drop-pressure effects in a quasi-steady model that was based on the Redlich-Kwong ~RK-EOS! equation of state ~@2#!. In a subsequent study ~@3#!, it was demonstrated that the effects due to thermody-namic nondealities and property variations modified the vaporiza-tion behavior significantly. Lazar and Faeth @4 # and Canada and Faet