Topological Optimization Design and Wave-Resistance Verification of Unmanned Sailboats

Abstract

With the growing demand for marine resource exploitation and environmental monitoring, wind-powered unmanned sailboats capable of long-endurance, long-distance missions have garnered increasing attention. This study presents a systematic topology optimization of the Fanhai-T2 unmanned sailboat to enhance its structural efficiency and hydrodynamic performance. Based on computational fluid dynamics (CFD) simulations and a fixed aspect ratio (A/R = 3.5), a wing sail using the NACA0018 airfoil was selected to maximize aerodynamic thrust while maintaining stiffness under adverse sea conditions. The SIMP method was then employed to perform component-level topology optimization of the wing sail, hull, keel, and rudder using material distribution as the design variable under volume constraints and a maximum stiffness objective. Post-optimization structural verification confirmed a 33.48% reduction in structural weight and a 34.38 mm decrease in the center of gravity height. Coupled CFD–FSI simulations under high-frequency regular waves demonstrated improvements in seakeeping behavior, with sway displacement, roll angle, roll moment, and wave resistance reduced by 48%, 43%, 24%, and 37%, respectively. Additionally, the structural mass ratio decreased from 90% to 45%, indicating improved material efficiency and adaptability to autonomous, long-duration maritime operations.

Keywords

Unmanned sailboat / Topology optimization / Lightweight / Finite element method / Wave-resistance verification

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Harbin Engineering University and Springer-Verlag GmbH Germany, part of Springer Nature