Slosh dynamics

"Slosh" redirects here. Not to be confused with SLOSH (model), Slosh (cue sport), Slash (punctuation), or Slush ice.
Water sloshing in the swimming pool of a cruise ship undergoing pitching motion

In fluid dynamics, slosh refers to the movement of liquid inside another object (which is, typically, also undergoing motion).

Strictly speaking, the liquid must have a free surface to constitute a slosh dynamics problem, where the dynamics of the liquid can interact with the container to alter the system dynamics significantly.[1] Important examples include propellant slosh in spacecraft tanks and rockets (especially upper stages), and the free surface effect (cargo slosh) in ships and trucks transporting liquids (for example oil and gasoline). However, it has become common to refer to liquid motion in a completely filled tank, i.e. without a free surface, as "fuel slosh".[not verified in body]

Such motion is characterized by "inertial waves" and can be an important effect in spinning spacecraft dynamics. Extensive mathematical and empirical relationships have been derived to describe liquid slosh.[2][3] These types of analyses are typically undertaken using computational fluid dynamics and finite element methods to solve the fluid-structure interaction problem, especially if the solid container is flexible. Relevant fluid dynamics non-dimensional parameters include the Bond number, the Weber number, and the Reynolds number.

Water sloshing in a glass cup

Slosh is an important effect for spacecraft,[4] ships,[3] some land vehicles and some aircraft. Slosh was a factor in the Falcon 1 second test flight anomaly, and has been implicated in various other spacecraft anomalies, including a near-disaster[5] with the Near Earth Asteroid Rendezvous (NEAR Shoemaker) satellite.

  1. ^ Moiseyev, N.N. & V.V. Rumyantsev. "Dynamic Stability of Bodies Containing Fluid." Springer-Verlag, 1968.
  2. ^ Ibrahim, Raouf A. (2005). Liquid Sloshing Dynamics: Theory and Applications. Cambridge University Press. ISBN 978-0521838856.
  3. ^ a b Faltinsen, Odd M.; Timokha, Alexander N. (2009). Sloshing. Cambridge University press. ISBN 978-0521881111.
  4. ^ Reyhanoglu, M. (23–25 June 2003). Maneuvering control problems for a spacecraft with unactuated fuel slosh dynamics. IEEE Conference on Control Applications. Vol. 1. Istanbul: IEEE. pp. 695–699. doi:10.1109/CCA.2003.1223522.
  5. ^ Veldman, A. E. P.; Gerrits, J.; Luppes, R.; Helder, J. A.; Vreeburg, J. P. B. (2007). "The numerical simulation of liquid sloshing on board spacecraft". Journal of Computational Physics. 224 (1): 82–99. Bibcode:2007JCoPh.224...82V. doi:10.1016/j.jcp.2006.12.020.