Simulation of van der Waals liquid droplets within a hot air atmosphere using the smoothed particle hydrodynamics method

The mass and heat transfer of van der Waals liquid droplets within a hot air atmosphere in microgravity have been studied using adaptive Smoothed Particle Hydrodynamics by assuming that the gas atmosphere is in contact with a thermal reservoir for a single-component two-dimensional system. A better definition of the diffuse interface between the phases was obtained through the introduction of a Korteweg tensor. As in previous works, the best initial particle distribution was obtained using the process of spinodal decomposition. The temperature obtained from the van der Waals cycle was compared with the temperature that arises from the integration of the conservation laws that contain the heat-flux vector. The calculated temperature profiles are the same for both the liquid and gas phases. The interface satisfies the condition of coexistence between the phases. In addition, the mass and heat transfer rates as well as the decrease of the drop radius were obtained for the three temperatures studied, finding that these are enhanced as the temperature of the reservoir is increased. Finally, it was possible to observe a damped oscillatory behavior of the temperature between the liquid phase and the interface for the first instants of time. We conclude that this is the mechanism by which the areas with lower temperature within the drop are heated before starting the mass transfer between the liquid and the gas phase.