Coupled aerodynamic characteristics of suction port position and angle of attack for suction-type turbosail

Abstract

To address the high carbon emissions of the shipping industry and help achieve the emission reduction targets set by the International Maritime Organization (IMO), this study investigates a suction-type turbosail for wind-assisted propulsion. Using Fluent with the Renormalization Group (RNG) k–ε turbulence model, the paper systematically explores the influencing mechanisms of the circumferential position of suction ports, sail angle, incoming flow angle of attack, and momentum coefficient on aerodynamic performance and flow field structures, with a focus on revealing the laws of boundary layer separation suppression and vortex shedding regulation. The results show that active suction effectively suppresses boundary layer separation, weakens trailing-edge vortex shedding, and substantially improves the aerodynamic performance of turbosail. The optimal operating range of the angle of attack is from −30° to −20°, where the thrust coefficient maintains a desirable level. More importantly, this work quantitatively establishes for the first time that the optimal circumferential layout of the suction port lies ∼10° downstream of the boundary layer separation point under the unsucked baseline condition. The inherent physical mechanism of synergistic effects among boundary layer momentum replenishment, adverse pressure gradient regulation, and wake vortex breakdown at this characteristic position is elaborated, enabling simultaneous optimization of turbosail thrust and aerodynamic efficiency. These findings provide theoretical guidance and engineering references for parameter optimization, structural design, and full-scale ship application of suction-type turbosails.