An improved macroscopic model for sloshing flow-combined porous structure interaction

Abstract

The design of the aquaculture tank system is important for fish survival, as it directly affects the behavior of farmed fish. To avoid violent liquid sloshing, this study proposes a side-mounted bracket-shaped perforated baffle and a special porous layer to explore their anti-sloshing performance. A macroscopic computational fluid dynamics (CFD) method, applicable to the combined porous structure, is developed by introducing the volume-averaged porous media theory, with corresponding experimental tests conducted. In this study, the macroscopic CFD method is first achieved to solve the fluid force on the perforated baffle by reasonably predicting the momentum flux through the porous surface. The microscopic model is also established to further verify the reliability of our proposed macroscopic model. The amplitudes of the free water surface and sloshing loads are adopted to assess the sloshing response. In addition, an index referred to as area-weighted-average velocity is introduced to quantify the kinetic energy. Results reveal that the established macroscopic model reliably replicates the free water surface and sloshing loads and greatly improves computational efficiency. Moreover, the high-frequency component of the wave energy is more easily dissipated, thus the transfer of energy from low frequency to high frequency resulting from the porous structure enhances its anti-sloshing performance, while conversely, the performance is weakened; the suppressing performance of the porous structure is closely related to the filling depth and excitation frequency, which dominate the frequency components of the sloshing behavior.