For efficient space exploration, the re-ignition technology of liquid rocket engines is essential. This engine system requires a stable propellant supply. During liquid rocket flight, the propellant tank is exposed to a reduced-gravity condition following engine cutoff. Therefore sloshing of liquid propellant occurs and the propellant supply system can be unstable. Reorientation simulations under a range of initial gravitational accelerations are performed to investigate the sloshing behavior that arises in reduced-gravity conditions. When the liquid propellant tank enters in microgravity condition, the free surface sloshes ane eventually settles into a new equivalent distribution. During this reorientation sequence, the free surface assumes a spherical shape and oscillates axisymmetrically except near the wall. This oscillation is dominated by surface tension, and its behavior is independent of the initial gravitational acceleration. However the height of the center is influenced by the initial wall because the rising of the contact line leads the descent of the center. The contact line moves upward along the wall, and the rate of its motion is influenced by the initial gravitational acceleration.
 

CFD,Microgravity,Reorientation,Liquid hydrogen