The green water is a highly non linear hydrodynamic phenomenon that occurs when the wave height exceeds the freeboard of the floating structures in harsh environments, and may compromise the operation and security of the on deck equipment. In the present study, in order to assess the effects of the green water phenomenon in FPSO and FLNG systems, the Moving Particle Semi-implicit (MPS) method, which is a fully lagrangian particle-method for incompressible flow, is adopted to model the complex fluid structure interaction problem. This article is focused on the recent developments of the MPS based simulation system of Numerical Offshore Tank (TPN-USP) and its application to the real scale offshore engineering problem. Results of large scale simulations using distributed memory architecture for models from 30 million to 100 million particles are presented
