Flow Structure and Surface Deformation of High Prandtl Number Fluid Under Reduced Gravity and Microgravity

The numerical simulation has been conducted to investigate the flow structure and surface deformation in a liquid bridge of high Prandtl number fluid under reduced gravity and microgravity. The Navier–Stokes equations coupled with the energy conservation equation are solved on a staggered grid, and the mass conserving level set approach is used to capture the free surface deformation of the liquid bridge. The effect of reduced gravity and thermocapillary convection on the surface deformation of the liquid bridge is investigated, and the results show that the amplitude of the surface horizontal vibration decreases gradually, and the thermocapillary convection inside the liquid bridge starts to turn into a steady state after the initial period. Moreover, the shift of the center of the recirculating flow inside the liquid bridge under horizontal external acceleration and zero gravity is also studied, and the results indicate that the vortex centers move initially toward the cold disk and reach an equilibrium position, and then the vortex centers vibrate around the equilibrium position periodically.