Seakeeping analysis of an amphibious vessel using CFD-modified potential (CMP) simulation and experimental validation

Abstract

This study introduces a hybrid simulation method, CFD-Modified Potential (CMP), that integrates Computational Fluid Dynamics (CFD) with potential flow methods to analyze the seakeeping performance of an amphibious vessel. The CMP procedure addresses the limitations of potential flow models, which are computationally efficient but neglect viscous effects, and CFD models, which are accurate but computationally intensive. By combining these approaches, CMP achieves both computational feasibility and enhanced accuracy. The method was used to predict roll and pitch damping ratios, derive Response Amplitude Operators (RAOs), and evaluate seakeeping performance. Results showed that CMP improved the accuracy of roll motion predictions in beam sea (90°) with errors below 5 % compared to experimental data. For pitch motion in head sea (120°–180°), significant improvements were observed when applying the CMP-derived damping ratio. Seakeeping performance predictions, particularly for roll motion, closely aligned with experimental results across all wave conditions, demonstrating CMP's reliability. While direct experimental data for pitch motion were unavailable, the method's robustness was validated through CFD-based comparisons. This study highlights CMP as a practical and reliable tool for accurate seakeeping performance assessments, minimizing the need for extensive experimental testing and supporting the design optimization of amphibious vessels.