To address the defects of traditional vertical flow sedimentators, such as low particle interception efficiency under high hydraulic loads and vulnerability to turbulent interference, this study designed a vortex-type vertical flow sedimentation filter. By integrating the principles of vertical flow sedimentation and cyclone separation, and combining CFD-DPM coupled simulation with experimental verification, the study systematically explored its enhanced removal mechanism for suspended particulates in recirculating aquaculture systems (RAS). Numerical simulations showed that the vortex structure optimizes the flow field distribution through the synergistic effect of centrifugal force and gravity, effectively suppressing particle escape. In comparative tests, under a hydraulic load of 15 m³/(m²·h), the vortex-type filter achieved interception rates of 72.92%±7.40% and 59.24%±5.15% for influent total suspended solids (TSS) concentrations of 25 mg/L and 50 mg/L, respectively, representing improvements of 28.6% and 36.0% compared to traditional devices (P<0.05). However, there was no significant difference in the variation of effluent TSS concentration with increasing flow rate between the two devices (P>0.05). The study demonstrates that the vortex design shortens the hydraulic retention time through a cyclone-enhanced mechanism, significantly improving the stability of particle interception under high-load conditions and addressing the performance degradation of traditional devices caused by increased flow velocity. This achievement provides a solution combining high efficiency and engineering applicability for optimizing solid-liquid separation equipment in RAS.
