TIME DOMAIN PREDICTION OF STEADY AND UNSTEADY MARINE HYDRODYNAMICS PROBLEM

Article type: Research Article

Authors: Kara, F. | Vassalos, D.

Affiliations: Ship Stability Research Centre (SSRC), Universities of Glasgow and Strathclyde, UK

Abstract: Numerical solutions for the hydrodynamic of bodies with forward speed are studied directly in the time domain using Neumann-Kelvin method. The exact initial boundary value problem is linearized using the free stream as a basis flow, replaced by the boundary integral equation applying Green theorem over the transient free surface Green function. The resultant boundary integral equation is discretized using quadrilateral elements over which the value of the potential is assumed to be constant and solved using the trapezoidal rule to integrate the memory or convolution part in time. The steady problem is solved as the steady state limit of the impulsive velocity of the surge radiation problem with forward speed. Calculation and general character of the transient free surface source potential or Green function is presented. The unsteady and steady results for the hydrodynamic problem, which is tested using Wigley hull form and hemisphere show the acceptable agreement with experimental, analytical and other published numerical results.

Journal: International Shipbuilding Progress, vol. 50, no. 4, pp. 317-332, 2003