A numerical study on the added resistance and motion of a ship in bow quartering waves using a soft spring system

• Published in: Ocean engineering 2023-07, Vol.280, p.114620, Article 114620
• Main Authors: Cho, Jun-Hui, Lee, Soon-Hyun, Oh, Dohan, Paik, Kwang-Jun
• Format: Article
• Language: English
• Subjects: Added resistance; Computational fluid dynamics (CFD); Oblique wave; Regular wave; Six degrees of freedom; Soft spring; Tanker
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2023.114620

The prediction of resistance performance in oblique waves have been a key issue for the accurate estimation of added resistance of ships in the actual operating state. Therefore, in this paper, the added resistance of a large tanker in the bow quartering waves (180⁰, 150⁰, 120⁰) was studied by applying a computational fluid dynamics (CFD) solver based on the unsteady Reynolds-averaged Navier-Stokes equations. In addition, the forces and motion responses in bow quartering waves according to the captive test (heave, roll, and pitch free) and soft spring test (6 DOF) were investigated. To validate the CFD results, it was compared with the model test results showing good agreement. The maximum value of the added resistance was observed between 180⁰ and 150⁰, and it decreased sharply at 120⁰. The peak of the added resistance moved to a shorter wave region. The differences in added resistance, heave, and pitch motions in oblique wave according to the degree of freedom were insignificant. However, the discrepancy in roll motion occurred due to the forces and moments differences caused by the degree of freedom. The tendency of added resistance in the bow quartering waves and the forces and motion responses according to the degree of freedom were also investigated. •URANS simulation for the ship by applying the soft-spring system in the bow quartering waves.•Additional resistance and motion during the bow wave between 180° and 120°.•The resonance frequency according to the relative angle between the wave and the ship.•The influence of heave, pitch, and roll motion according to the DOF in the bow quartering waves.