Effects of Sloshing Dynamics on Fuel Acquisition in Satellites at Zero Gravity
Simulation provided by The Boeing Company.
Knowledge of the motion of propellants in the fuel tanks of spacecraft is essential to understanding various aspects of their operation and performance. Propellant motion impacts such propulsion functions as expulsion of liquid, venting of gases, and pressurization. In some cases the forces produced by the propellant motion must also be known. This is particularly true when the liquid mass is a significant portion of the total spacecraft mass.
The animation above shows the results of a three-dimensional sloshing analysis. TruVOF, the Volume-of-Fluid (VOF) method used by FLOW-3D makes these types of calculations possible. Additional physical models permit one to use non-inertial reference frames and to include rigid body dynamics.
Ref. "Comparison of FLOW-3D Calculations With Very Large Amplitude Slosh Data," Computational Experiments, PVP - Vol. 176, ASME, 1989).
Sloshing Simulation Examples
Sloshing of aircraft fuel stored within the wing using FLOW-3D's Non Inertial Reference Frame Model
while the aircraft goes through a simplified yaw, pitch and roll acceleration executing a turn.
The sloshing of liquid oxygen fuel tanks destined for space illustrates the hazards of unconstrained
motion. This simulation shows the unrestrained behavior of liquid oxygen shaken laterally at
3 Hz and .1 G. The tank, undergoing rotation, is 5 meters in diameter by 10 meters in length.
The ullage pressure is maintained at 1.02 bar by a separate, ignored system and is being drained at
500kg per second. This highly transient behavior is accurately captured by the TruVOF technique
used in FLOW-3D. The color scale represents the velocity magnitude for each control volume.