首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Long-term response analysis of FPSO mooring systems
Authors:AO Vázquez-Hernández  GB Ellwanger  LVS Sagrilo
Institution:aInstituto Mexicano del Petróleo, Deep Waters Explotation Department, Eje Central Lázaro Cárdenas Norte 152, Gustavo A. Madero, 07730, México, D.F., Mexico;bCOPPE – Federal University of Rio de Janeiro, Civil Engineering Department, Cidade Universitária, Centro de Tecnologia, Bloco I-2000, Sala I-116, Ilha do Fundão 21945-970, Rio de Janeiro, Brazil
Abstract:The design of mooring systems for floating production units usually considers extreme environmental conditions as a primary design parameter. However, in the case of FPSO (Floating, Production, Storage and Offloading) units, the worst response for the mooring system may be associated with other sea state conditions due to the fact that its extreme response may be associated with a resonant period instead of an extreme wave height. The best way to deal with this problem is by performing long-term analysis in order to obtain extreme response estimates. This procedure is computationally very demanding, since many short-term environmental conditions, and their associated stochastic nonlinear time domain numerical simulations of the mooring lines, are required to obtain such estimates. A simplified approach for the long-term analysis is the environmental contour-line design approach. In this paper a Monte Carlo-based integration procedure combined with an interpolation scheme to obtain the parameters of the short-term response distribution is employed to hasten the long-term analysis. Numerical simulations are carried out for an FPSO at three different locations considering a North Sea joint probability distribution for the environmental parameters. The long-term analysis results are compared against those obtained using extreme environmental conditions and environmental contour-line methodology. These results represent the characteristic load effect for the design of mooring systems of floating units using the reliability analysis for mooring line. The results show that the long-term results are usually more critical than those obtained with the other approaches and even different mooring lines can be identified as the critical ones.
Keywords:Mooring systems  Long-term analysis  Monte Carlo simulation
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号