Hydrodynamic Analysis of Floating Barge with Different Drafts due to Waves in Frequency Domain

In this paper, the responses of a floating barge in waves under hydrodynamic loads are investigated using the BEM-based ANSYS AQWA software. Usually marine vehicles are faced to sea waves with different heights and frequencies during their life. Due to different loads, their locations and tonnages a barge in operational conditions may have different drafts. Furthermore, in most of the time, the loading is more than regular tonnage, which causes critical situations of sea keeping. The aim of this paper is to study the effect of wave direction and barge draft on coupled motions of a floating barge in six degrees of freedom. For this purpose at first the results at design waterline are compared and verified with Newman’s results. Then responses are evaluated in different water lines and wave directions. Results show that the maximum values of Froude Krylov and diffraction forces occur in Yaw motion for 45⁰ waves of 12 seconds period. However the Froud Krylov-diffraction forces occur in roll motion for ±90⁰ waves of 8 second period. Nevertheless, there are not any perceptible changes in structural responses for waves with periods greater than 19 seconds.