Developments and application of fish school swimming model in recirculating aquaculture systems

The hydrodynamics of aquaculture tanks are essential in recirculating aquaculture systems to enhance fish growth and development. However, existing studies on the hydrodynamics of these tanks frequently ignore the presence of fish, making it difficult to understand the complex and variable interactions between the flow field and cultured fish. The presence of fish and their swimming significantly affects the flow field dynamics of the tanks. This study used computational fluid dynamics (CFD) to examine the flow regime affected by fish swimming motion and its impact on the flow field. We found that (i) CFD can accurately simulate the impact of fish swimming motion on the flow field, as validated by physical modeling experiments. (ii) The presence and swimming of fish can negatively affect the flow conditions in the tank to varying degrees. (iii) Adjusting the inlet velocity is one of the most effective methods for optimizing the flow field conditions. The numerical model developed in this study, which couples fish population dynamics with the aquatic environment, enabling accurate simulation of hydrodynamic mechanisms influenced by fish and structural parameters. This model provides a valuable reference for enhancing aquaculture practices in recirculating aquaculture systems. •A CFD model for fish school dynamics and aquatic environment was developed.•The affect of fish school swimming on the flow field in the tank was investigated.•It was found that adjusting inlet velocity optimizes tank flow performance.•Energy utilization for aquaculture welfare and economic efficiency was analyzed.