Dynamics for Droplets in Normal Gravity and Microgravity

A numerical study has been carried out to investigate the deformation dynamics of droplets under normal gravity and the thermocapillary migration of droplets under microgravity. The Navier–Stokes equations coupled with the energy conservation equation are solved on a staggered grid by the method of lines, and the mass conserving level set method is used to predict the surface deformation of the droplet. The simulation for the falling droplet in the air under normal gravity shows that the value of Weber number affects mainly the deformation of the droplet, while the value of Reynolds number has direct impact on the falling velocity of the droplet. From the simulation for the droplet thermocapillary migration and lateral oscillation under microgravity, it is found that the value of Marangoni number has obvious effects on the moving velocity and temperature distribution of the droplet.