A novel approach to full-scale ship resistance predictions: experimental and numerical study of a high-speed planing hull

This study investigates the scale effect on resistance predictions for high-speed planing hulls through a combination of experimental and numerical approaches. Resistance tests were conducted at Istanbul Technical University's Ata Nutku Ship Model Testing Laboratory using a 1/10 scale model of an innovative 15 m semi-submersible naval vessel. Computational Fluid Dynamics (CFD) simulations were performed at eight different scales, including inviscid flow conditions (in which the flow was modeled by Euler’s momentum equation), for both pre-planing and planing regimes. Unsteady Reynolds averaged Navier–Stokes equations (URANSE) were solved using three different eddy viscosity models. The numerical setup was validated against experimental data, with verification and validation analyses performed according to ITTC guidelines. Results showed that residuary resistance coefficient remains nearly constant at pre-planing regime while slightly decreasing with increasing Reynolds number at planing regime. A new extrapolation methodology was proposed combining model-scale experimental data with inviscid flow simulation results, avoiding traditional assumptions about resistance decomposition. The proposed method demonstrated better agreement with full-scale CFD predictions compared to traditional extrapolation approaches, with relative differences of approximately 1% versus 2.73% for the traditional method. Additionally, this study provides uncertainty estimates for full-scale resistance predictions, offering a more comprehensive understanding of prediction accuracy. These findings contribute to improving the reliability of resistance predictions for high-speed planing hulls and provide insights into the scale effects on different resistance components.