Effect of length-width ratio of rounded rectangle aquaculture tank in dual-diagonal-inlet layout on hydrodynamics

To adapt to the change of aquaculture workshop site, optimize the shape of aquaculture tanks and improve the utilization rate of breeding space, it is necessary to determine the appropriate length-width ratio parameters of aquaculture tanks. In this paper, computational fluid dynamics (CFD) technology is adopted to study the flow field performance of aquaculture tanks with different L/B ratios (L: the length; B: the width, of aquaculture tank) and different jet direction conditions (lengthways jet and widthways jet). A three-dimensional numerical calculation model of turbulence in rounded rectangle aquaculture tanks in dual-diagonal-inlet layout was established. Jet directions are arranged lengthways and widthways, and the water flow velocity, resistance coefficient change, vorticity, etc. are analyzed under two working conditions. Results show that the flow field performance in aquaculture tank decreases with the increase of the L/B ratio. The flow field performed well when L/B was 1.0–1.3, sharply dropped at 1.4–1.6, and poor at 1.7–1.9. The results provided a theoretical basis for the design and optimization in flow field performance of the industrialized circulating aquaculture tanks.