The paper is concerned with the simulation of mechanically coupled bodies in seaway. While the applications of such cases are very wide, they are of particular interest for offshore operations, e.g. towing and boat landing. The focus of the present study is to supplement a viscous flow solver by appropriate mechanical models to analyse the hydrodynamics of coupled bodies due to mechanical joints. A quaternion-based motion modeller has been implemented using several basic joint elements to model their influence in a multi-body system. Examples included refer to rigid links, ropes, fenders or guide frames to restrict the motion in experiments, and aim to illustrate the predictive accuracy of the procedure and generic applications utilising all features of the computational framework including an overset grid technique.
