Hydrodynamic Analysis and Performance Evaluation of a Ship in Irregular Sea Conditions

The maritime industry, a critical global trade facilitator, necessitates the movement of goods and passengers across the world’s oceans. Ships, the backbone of this industry, encounter diverse environmental conditions, from calm waters to tumultuous seas. Among these challenges, irregular sea conditions have gained increasing attention among naval architects, marine engineers, and safety regulators. The extremes in ship motions and loads, induced by severe sea states, pose a significant threat to ship and cargo safety. This study focuses on the hydrodynamic response of a ship in irregular sea conditions, with a particular emphasis on vertical plane motions (heave, pitch, and roll). The approach involves the generation of irregular wave scenarios based on wave spectral models, employing computer-aided design and ANSYS software. Time domain simulations offer a nuanced perspective on the ship’s dynamic behavior. It concentrates on long crested wave scenarios and considers three specific spectral models; Pierson- Moskowitz, Bretschneider, and JONSWAP. The study refrains from examining structural or material aspects of ship design and omits the consideration of viscous effects. The most extreme vertical responses were observed under the Pierson Moskowitz Sea state to be -0.44291m heave and 0.68986˚ pitch during the simulation time of 300s, whilst JONSWAP resulted in the most extreme roll motion of 3.69873e-3˚. The methodology and results provide critical insights for naval architects, marine engineers, and safety regulators as they navigate the complexities of irregular sea conditions. This research emphasizes the impact of wave spectra on ship behavior, bridging the theoretical and practical aspects of maritime operations in ship hydrodynamics