Experimental and numerical investigations of advancing speed effects on hydrodynamic derivatives in MMG model, part I: Xvv,Yv,Nv.

Abstract Experimental and numerical studies on the hydrodynamic forces and moments of the ONR Tumblehome (ONRT) hull during oblique towing tests are performed. The experiments are carried out in the towing tank of Marine Design and Research Institute of China (MARIC) and the numerical simulations are based on the open-source CFD library OpenFOAM. Validations of the numerical methods are provided by comparison with experimental measurements from tests at two advancing speed. And then the investigations of advancing speed effects on hydrodynamic derivatives used in MMG model are performed numerically. Specifically, X v v , Y v , N v of the ONRT hull at four advancing speed are yielded via linear regression of the hydrodynamic forces and moments predicted by CFD calculations. Finally, the relationship between hydrodynamic derivatives and advancing speed are concluded and the expressions of hydrodynamic derivatives that can be used in MMG model are given. Highlights • Experimental and numerical methods are used to investigate the hydrodynamic forces and moment of the ONRT hull during oblique towing tests and the experimental measurements and numerical results are well validated. • The idea, proposed in this work, that considers a varying hydrodynamic derivatives in the MMG model is new. And considering the speed loss during maneuvering motions of a ship, it is reasonable to take the advancing speed effects on the hydrodynamic derivatives into account. • Numerical simulations of the oblique towing tests at four different advancing speed are performed and the expressions of hydrodynamic derivatives in the form of advancing speed are given. These expressions can be used in the MMG model as varying hydrodynamic derivatives. [ABSTRACT FROM AUTHOR]