Numerical Investigation of Sloshing Under Roll Excitation at Shallow Liquid Depths and the Effect of Baffles

Abstract

Sloshing is relevant in several applications like ship tanks, space and automotive industry and seiching in harbours. Due to the relationship between ship and sloshing motions and possibility of structural damage, it is important to represent this phenomenon accurately. This paper investigates sloshing at shallow liquid depths in a rectangular container using experiments and RANS simulations. Free and forced sloshing, with and without baffles, are studied at frequencies chosen specifically in proximity to the first mode natural frequency. The numerically calculated free surface elevation is in close agreement with observations from experiments. The upper limit of the resonance zone, sloshing under different filling depths and roll amplitudes and sloshing with one, two and four baffles are also investigated. The results show that the extent of the resonance zone is reduced for higher filling depth and roll amplitude. It is also found that the inclusion of baffles moves the frequency at which the maximum free surface elevation occurs, away from the fundamental frequency. Finally, a submerged baffle is found to dissipate more energy compared to a surface piercing baffle and that the effect of several submerged baffles is similar to that of a single submerged baffle.

Keywords

Sloshing / Baffles / Resonance / Numerical modelling / REEF3D

Funding

NTNU Norwegian University of Science and Technology (incl St. Olavs Hospital - Trondheim University Hospital)