On the evaluation of quadratic forces on stationary bodies
- 51 Downloads
Conservation of momentum is applied to a finite fluid volume surrounding a body and enclosed by a control surface in order to obtain expressions for all components of quadratic forces and moments acting on the body in terms of the momentum flux and the change of the momentum in the fluid volume. It is shown that the expressions derived are essentially identical with those obtained by a complementary approach given by Dai et al. (2005, computation of low-frequency loads by the middle-field formulation. In: Grue J (ed) 20th workshop for water waves and floating bodies. Longyearbyen, Norway, pp 47–50) where the pressure integrals on the body surface are transformed into integrals on the control surface using various vector theorems. Computational results limited to the mean drift forces are presented to illustrate the advantages of using control surfaces.
KeywordsControl surface Mean drift force Momentum conservation Pressure integration Quadratic force
Unable to display preview. Download preview PDF.
- 1.Pinkster JA (1980) Low frequency second-order exciting forces on floating structures. NSMB Report 650Google Scholar
- 2.Ogilvie TF (1983) Second-order hydrodynamic effects on ocean platforms. In: Young RW (ed) International workshop on ship and platform motions. Berkeley, CAGoogle Scholar
- 3.Molin B, Hairault J-P (1983) On second-order motion and vertical drift forces for three-dimensional bodies in regular waves. In: Young RW (ed), International workshop on ship and platform motions. Berkeley, CAGoogle Scholar
- 4.Lee C-H, Newman JN (1991) First- and second-order wave effects on a submerged spheroid. J Ship Res, 35:183–190Google Scholar
- 6.Newman JN (1967) The drift force and moment on ships in waves. J Ship Res 11:51–60Google Scholar
- 7.Lee C-H, Newman JN (1992) Sensitivity of wave load to the discretization of bodies. Proceedings of behaviour of offshore structures. LondonGoogle Scholar
- 8.Lee C-H, Farina L. Newman JN (1998) A geometry-independent higher-order panel method and its application to wavebody interactions. In: Tuck EO, Stott JAK (eds) Proceedings of Engineering Mathematics and Applications Conference, Adelaide, Australia pp 303–306Google Scholar
- 9.Ferreira MD, Lee C-H (1994) Computation of second-order mean wave forces and moments in multibody interaction. In: Chryssostomidis C (ed) Proceedings of Behaviour of Offshore Structures Vol Cambridge, MA. pp 303–313Google Scholar
- 10.Dai Y-S, Chen X-B, Duan W-Y (2005) Computation of low-frequency loads by the middle-field formulation. In: Grue J (ed) 20th workshop for water waves and floating bodies. Longyearbyen, Norway, pp 47–50Google Scholar
- 11.Newman JN (1980) Marine hydrodynamics. The MIT PressGoogle Scholar
- 12.Hildebrand FB (1976) Advanced calculus for engineers. Prentice-HallGoogle Scholar