Heading Analysis of Weathervaning Turret Moored Units

Abstract

This paper presents the heading analysis study of weathervaning turret moored unit. Design wave heading is to be in accordance with the operational conditions for the sea states contributing the most to the long term value of the dominant load effect. From the heading analysis over each of the sea states contained in the time-series, the mean heading of the floating structure can be obtained.The objective of this study is to assess heading analysis outcome as function of heading probability occurrences of weathervaning turret moored floating units and to identify dominance environment load component act to the system.In order to achieve the above objective, the numerical model has been developed. The model is generate a vessel model by describing the capability to weathervane. It will be performed with MOSES software packages and numerical tools, both in the time-domain and frequency-domain.The heading analysis results indicates that the most affected external forces is dedicated by wind, it is seen the relative heading between wind and vessel heading is quite small (<10degree) with large occurrence probability (up to 60%). The proposed double static approach method to solve heading analysis has been investigated by comparing to former approach which is found a good result agreement between them.