Hydrodynamic Force Corrections for Model Tests in a Narrow Wave Tank

Abstract

During physical model tests of offshore structures in narrow wave tanks, wave reflections from the tank walls may substantially affect the hydrodynamic pressures and forces on the structure when compared with the values that would be experienced in the open sea. A number of recent papers have given theoretical models for the scattering and radiation of waves by specific bodies in a narrow wave tank, and this body of work gives valuable insight into tank confinement effects. The question arises: “Can the open sea characteristics be deduced solely from measurements of the wave field made in the tank, and without resort to detailed numerical calculations for the particular structure concerned?” This question is addressed in the present work in which a method is presented for constructing the open-sea scattered wave field solely from knowledge of the wave field in a narrow tank. Here the method is used to correct the mean drift force on a vertical, circular cylinder.