Hydrodynamic Characteristic of the “ChangJiangKou II” Wreck Salvage: A Coupled Time Domain Model

Abstract This paper reports an integral salvage solution for an ancient vessel “Chang Jiang Kou II” wreck salvage. To ensure the safety of the whole salvage operation and reduce the damage to the historical relic, especially in the off-bottom and lifting process, a novel coupled time-domain model is developed to evaluate the safety of the moored salvage system in Yangtze River. The wreck-soil interaction module, lifting module and mooring module are coupled into the conventional potential flow time domain numerical simulation code. The finite element method, potential flow method and lumped mass method are adopted and integrated for considering the influence of the wreck-soil interaction, lifting and mooring system. The coupled model is preliminary validated by similar mature software in our previous study and is further validated by a model-scale experiment in present paper. The safety assessment is quantitatively conducted by using a three-parameters safety assessment methodology. Case studies with different sea states are numerically performed and quantitatively assessed. The results of the numerical simulation and experiments found that there is a special breakout phenomenon, where the displacements increase abruptly, and uneven distributions of the lifting tensions are observed. The outcome of present coupled model can give an important reference in real salvage operation.