A Far Field Solution of the Slowly Varying Drift Force on the Offshore Structure in Bichromatic Waves-Three Dimensional Problems
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A far field approximate solution of the slowly varying force on a 3 dimensional offshore structure in gravity ocean waves is presented. The first order potential, or at least the far field form of the Kochin function, of each frequency wave is assumed to be known. The momentum flux of the fluid domain is formulated to find the time variant force acting on the floating body in bichromatic waves. The second order difference frequency force is identified and extracted from the time variant force. The final solution is expressed as the circular integration of the product of Kochin functions. The limiting form of the slowly varying force is identical to the mean drift force. It shows that the slowly varying force components caused by the body disturbance potential can be evaluated at the far field.
Abstract
A far field approximate solution of the slowly varying force on a 3 dimensional offshore structure in gravity ocean waves is presented. The first order potential, or at least the far field form of the Kochin function, of each frequency wave is assumed to be known. The momentum flux of the fluid domain is formulated to find the time variant force acting on the floating body in bichromatic waves. The second order difference frequency force is identified and extracted from the time variant force. The final solution is expressed as the circular integration of the product of Kochin functions. The limiting form of the slowly varying force is identical to the mean drift force. It shows that the slowly varying force components caused by the body disturbance potential can be evaluated at the far field.
참고문헌 (7)
- Chen,X.B, "Middle-field Formulation for the Computation of Wave-drift Loads", Journal of Engineering Mathematics, 59(1), pp.61~82 (2007)
- Dai, Y.S, "Computation of Low-frequency Loads by the Middle-field Formulation", 20th International Workshop for Water Waves and Floating Bodies, pp.47~50 (2005)
- Kim, M.H, "The Complete Second-order Diffraction Solution for an Axisymmetric Body - Part 2. Bichromatic Incident Waves and Body Motions", Journal of Fluid Mechanics, 211, pp.557~593 (1990)
- 이상무, "A Far Field Solution of the Slowly Varying Drift Force on an Offshore Structure in Bichromatic Waves - Two Dimensional Problems", 한국해양공학회지, 22(2), pp.7~12 (2008), 한국해양공학회
- Maruo,H, "The Drift of a Body Floating in Waves", Journal of Ship Research, pp.1~10 (1960)
- Newman,J.N, "The Drift Force and Moment on Ships in Waves", Journal of Ship Research, 11, pp.51~60 (1967)
- Pinkster,J.A, "Mean and Low Frequency Wave Drifting Forces on Floating Structures", Ocean Engineering, 6, pp.593~615 (1979)