Sensitive Analysis of Different Types of Deep Water Risers to Conventional Mooring Systems

Authors

1 B.Sc., Faculty of Marine Engineering, Petroleum University of Technology

2 Assistant Professor, Faculty of Marine Engineering, Petroleum University of Technology

Abstract

Structural response of different types of conventional deep water riser affected by mooring systems in harsh environment is focused in this study. With increasing water depth, the mooring system design of a floating-type production platform becomes more important and complicated from cost as well as safe operation point of view. With the development of offshore oil and gas exploitation, FPSO with many advantages can better adapt to the complicated environment of deep sea. According to the current mooring system development, this study compares the effect of spread mooring system and turret mooring system on riser structural response. Both systems consists of 12 mooring lines and each line is made from two components. Three types of more conventionally used deep water risers have been selected and applied with the mooring systems, resulting in 6 different case studies. The case studies have been modeled in OrcaFlex software with same extreme environmental conditions. Comparing bending moment in the risers, as one of the main design parameter, shows the effect of proper selection of the riser and mooring system.

Keywords


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