CFD-based design of novel drag-reducing appendages for container ships

Container ships, as cornerstones of modern global trade, have significantly increased in size in recent years. This growth necessitates minimizing resistance to environmental forces to improve operability, enhance safety, and reduce fuel consumption. While aerodynamic optimization has traditionally focused on windshields and container stacking configurations, this study introduces a novel drag-reducing appendage inspired by sports aerodynamics engineering. The research follows a two-stage approach. First, a numerical model was validated against experimental wind tunnel results, achieving a high correlation with less than a 2 % difference in drag coefficient. Second, the validated model was used in computational fluid dynamics (CFD) simulations to assess the effectiveness of various appendage designs. A parametric study was conducted to optimize appendage placement, size, and orientation, leading to two configurations that achieved maximum drag reductions of 9.47 % and 9.22 %, respectively. Results indicate that these appendages mitigate adverse pressure effects and streamline flow around the accommodation block, effectively reducing aerodynamic drag. This study demonstrates the feasibility of integrating simple, cost-effective appendages to enhance the aerodynamic performance of post-panamax container ships without compromising cargo capacity. The findings provide a practical approach for reducing fuel consumption and emissions, supporting ongoing efforts toward sustainable shipping.