Papers of Significance

Conversion of a tanker into a FPSO

Authors:  Dimitris G. Georgiadis, Emmanuel S. Samuelides
Division of Marine Structures, School of Naval Architecture and Marine Engineering, National Technical University of Athens, Greece
Published by:  Hellenic Institute of Marine Technology
Abstract:  The paper presents the conversion of an oil tanker into FPSO considering strength criteria. Also, a reliability assessment of FPSO hull girder is conducted based on initial yield and ultimate strength. From the first perspective, we look into the influence of the anticipated operation site of the FPSO on the volume of replacements and repairs needed. In particular, it is investigated how the operating site affects the requirements and consequently, the decision to proceed with the conversion or not. Two areas with different environmental conditions have been selected as operation sites, one in the North Sea and one offshore Nigeria. Two shipyards, one in Singapore and one in Spain, have been selected as a departure location for each site in order to define the most unfavorable transit condition regarding loads induced by wave. The methodology followed for the conversion procedure is based on ABS (2015) ‘‘Rules for building and classing Floating Production Installations’’. For the reliability analysis, a First Order Reliability Method (FORM) is employed in order to quantify the uncertainties of loads and resistance and derive the probability of failure for the two limit states investigated. A numerical application is implemented in order to demonstrate the capability of the analysis developed.  Click here for full paper

Design of new generation LNG carriers

Authors:           M Faou, S Roche, C H Jin, P Corrignan, P Marty, C Wandji
Published by : Association Technique Maritime et Aéronautique
Abstract:         TOTAL SA, the Korean Shipyard SAMSUNG HEAVY INDUSTRIES and BUREAU VERITAS have teamed up, within the scope of a Joint Industry Project, to design a new generation of 180000m3 LNG carrier with high energy efficiency considering future LNG trading patterns, new trading route and compliance with future environmental regulations. For this purpose, a full hull form, propulsion and power generation optimization has been performed for a pre-defined complete operational profile of the ship (i.e. full voyage including loading and unloading operations, maneuvering, channeling, etc.). The hull lines have been optimized by BV subsidiary HydrOcean using state-of-the-art Navier–Stokes Computational Fluid Dynamics (CFD tools), considering both calm water performance and ship behavior in waves. The performance of the final design has been validated by calm water and seakeeping model tests.  Click here for full paper   

Ship-ship hydrodynamic interaction in confined waters with complex boundaries by a panelled moving patch method

Authors:           X-Q Zhou, S Sutulo, C Guedes Soares

Published by:  The Royal Institution of Naval Architects in the International Journal of Maritime Engineering

Abstract:          This paper presents a potential flow solution for online estimation of hydrodynamic interaction between ships moving in restricted waters with complex boundaries. Each ship in concern is linked with a moving patch representing the arbitrary bathymetry beneath it. The wetted surfaces of ship hulls are meshed and loaded prior to the simuation, while the moving patches are dynamically discretized by a fast and robust mesh generator. The proposed method is validated for the ship-ship interaction case in the shallow water case with a flat and horizontal seabed where the mirror image technique is applicable, and satisfactory agreement is obtained. The method is further applied to simulate two interaction scenarios involving arbitrary seabed topography, and the numerical results are obtained and discussed.   Click here for full paper