Hydrodynamic analysis of the offshore floating nuclear power plant

Abstract

Hydrodynamic analysis of two models of the Offshore Floating Nuclear Plant [91 was conducted. The OFNP-300 and the OFNP-1100 were both exposed to computer simulated sea states in the computer program OrcaFlex: first to sets of monochromatic waves, each consisting of a single frequency and waveheight, and then to Bretschneider and JONSWAP spectra simulating 100-year storms in, respectively, the Gulf of Mexico and the North Sea. Hydrodynamic coefficients for these simulations were obtained using a separate computer program, WAMIT. Both models exhibited satisfactory performance in both heave and pitch. An alternative design of the OFNP-300 was developed and similarly analyzed in attempt to further improve hydrodynamic performance. A catenary mooring system was designed and analyzed for both plant models. The number of chains and the length of each were selected to ensure the mooring systems would withstand, with sufficient margins of safety, the maximum tension produced in a 100-year storm. This analysis was conducted both with all the designed mooring lines intact, and with the worst-case line broken. A lifecycle cost analysis of various mooring systems was conducted in order to minimize the cost of the mooring system while maintaining adequate performance.