In this paper, a new procedure for hydrodynamic load assessment of Energy Saving Devices (ESD) is proposed. The procedure consists of three main parts, sea-keeping analysis, Computational Fluid Dynamics (CFD) analysis and long-term analysis. In sea-keeping analysis, Response Amplitude Operators (RAO) and response spectrums of vertical velocity at ESD are calculated. In CFD analysis, hydrodynamic force are calculated for pre-defined regular waves and a neural network is trained for the data. In order to consider the randomness of the irregularity, twenty different irregular time histories are generated from the response spectrums. Then, each time history of vertical velocity is converted to hydrodynamic force using the neural network. Gumbel distribution is used to fit the hydrodynamic force and long-term response is calculated. An approximate long-term calculation is made using contribution coefficient method that enables to perform time domain analysis for a few sea states that have dominant contributions to long-term response.
展开▼
