LONG TERM PREDICTION OF WAVE LOADING AND BENDING-TORSION STRENGTH ANALYSIS OF OPEN HATCH SHIP ON ENTIRE SHIP FE MODEL

The accurate calculation of bending-torsion combined deformation and stress of anopen hatch ship must be done on an entire model of ship hull. As an example, calculationof a 50,000 DWT open hatch ship is introduced in this paper. By a 3-D radiation-diffrac-tion hydrodynamic program the long term prediction of wave induced motion and loading isperformed, based on which a group of design waves are defined. The bending-torsion com-bined deformation and stress in each part of main structural members of ship hull on de-sign waves are calculated by an FE model of entire ship hull. A local model of open hatchcorner with refined FE mesh is inserted in entire ship model and the stress concentration athatch corner is shown out simultaneously with whole ship analysis. The properties ofwave loading on a ship, the way of defining design waves, the way of FE calculation for anentrie ship and the inertia equilibrium of floating body are described. All direct calculationwork are performed by DNV'S SESAM system.