A comparison study of water impact and water exit models
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참고문헌
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초록
In problems of global hydroelastic ship response in severe seas including the whipping problem, we needto know the hydrodynamic forces acting on the ship hull during almost arbitrary ship motions. In terms of ship sections,some of them can enter water but others exit from water. Computations of nonlinear free surface flows, pressure distributionsand hydrodynamic forces in parallel with the computations of the ship motions including elastic vibrations ofthe ship hull are time consuming and are suitable only for research purposes but not for practical calculations. In thispaper, it is shown that the slamming forces can be decomposed in two components within three semi-analytical modelsof water entry. Only heave motion is considered. The first component is proportional to the entry speed squared and thesecond one to the body acceleration. The coefficients in these two components are functions of the penetration depthonly and can be precomputed for given shape of the body. During the exit stage the hydrodynamic force is proportionalto the acceleration of the body and independent of the body shape for bodies with small deadrise angles.
Abstract
In problems of global hydroelastic ship response in severe seas including the whipping problem, we needto know the hydrodynamic forces acting on the ship hull during almost arbitrary ship motions. In terms of ship sections,some of them can enter water but others exit from water. Computations of nonlinear free surface flows, pressure distributionsand hydrodynamic forces in parallel with the computations of the ship motions including elastic vibrations ofthe ship hull are time consuming and are suitable only for research purposes but not for practical calculations. In thispaper, it is shown that the slamming forces can be decomposed in two components within three semi-analytical modelsof water entry. Only heave motion is considered. The first component is proportional to the entry speed squared and thesecond one to the body acceleration. The coefficients in these two components are functions of the penetration depthonly and can be precomputed for given shape of the body. During the exit stage the hydrodynamic force is proportionalto the acceleration of the body and independent of the body shape for bodies with small deadrise angles.
참고문헌 (19)
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