Validation of Second-order Analysis in Predicting Diffracted WaveElevation Around a Vertical Circular Cylinder

摘要

In the present paper, the focus is on water wave diffraction around arnsingle, fixed vertical circular cylinder subjected to monochromaticrnincoming waves. The study involves waves of different steepnessesrnand periods. The wave elevation at various locations around therncylinder is considered.rnNumerical simulations of first and second order diffraction, by meansrnof potential theory, using an industry standard numerical toolrn(WAMIT, 1995) are conducted. A convergence study of the secondrnorder diffraction is presented, and numerical results are compared tornmodel test data from the MARINTEK Towing tank. Moreover, thernvalidity of the second-order approach is investigated. Magnitudes ofrnthird- and higher order contributions are evaluated from thernmeasurements in the higher harmonics as well as in the basicrnharmonic and the mean set-up.