Analysis On Hydrodynamic Coefficients Of A Cylinder With Nested Heave-plates

Based on the potential flow theory, WAFDUT1.4, a program developed by Dalian University of Technology, was used to study the exciting force and hydrodynamic coefficients of a single circular and square plate, multiple square plates and a cylinder with nested plates.The program is based on a higher-order boundary element method (BEM), and a self-adaptive Gaussian integration method was adopted for the evaluation of nearly singular integrals in elements.The numerical experiment was carried out and the exciting force and hydrodynamic coefficients of a single circular plate, a single square plate, multiple square plates of the Spar platform and a cylinder with nested heave-plates in different cases were analyzed. For the multiple square plates, the comparisons between numerical results and experimental results of Prislin etc al show that added mass of heave plates in real fluid is about1.1times of that in potential assumption. For the cylinder with nested heave-plates, those heave-plates increase the total vertical added mass and thus decrease the heave motion. This can be a good reference for some new offshore structures in the future.