Tm GASIFICATION behavior of a liquid droplet provides a fundamental input for the modeling of many spray systems, and has been studied extensively [l-4]. Theoretical analysis for the multicomponent fuel droplet presents several complexities absent in a similar analysis for the single component droplet. First, the phase-change process at the droplet surface and the transport of a fuel vapor mixture in the gas phase need to be properly described. Second, the evaporation process is inherently time varying due to the continuous change in the composition and temperature of the droplet as vaporization proceeds. Another difference between the two cases is due to the phenomenon of microexplosion [2]. The earlier viewpoint [2] of multicomponent droplet vaporization assumes that the composition and temperature within the droplet are spatially uniform but time varying. Such theories predict that the gasification process is similar to batch distillation in that the sequence of gasification is controlled by the volatility differentials among the different components. However, Sirignano [4] showed that even in the limit of high vortex strength, the internal liquid circulation can only reduce the characteristic length scale for diffusion by a factor of three. Landis and Mills [S] investigated the vaporization of a bi-component fuel droplet in a stagnant atmosphere. A quasi-steady gas-phase model was used and the equations governing the unsteady mass and heat diffusion within the droplet were solved numerically. Results when compared with rapid mixing behavior showed significant differences. A unique feature of the diffusion-dominated droplet gasification mechanism is the possible attainment of approximately steady-state temperature and concentration profiles within the droplet, which then leads to a steady-state gasification rate. Based on this concept, Law and Law [6] formulated a d2-law model for multicomponent droplet vaporization and combustion. As indicated above, the literature on the gasification behavior of an isolated droplet is extensive. However, most of these studies deal with droplet combustion or evaporation under high-temperature conditions. Not much information is available on the behavior of evaporating droplets in relatively low-temperature air streams. Under such conditions, the possibility of an envelope flame is precluded and the droplet gasification rate is low. The droplet heat-up time may not be negligibly small compared to its lifetime, although the latter is relatively large and the liquid-phase transient processes may still be important. In this paper, the vaporization behavior of pure and multicomponent fuel droplets flowing in a well-characterized laminar flow is studied. The predictions of three vaporization models are compared with the experimental data.