The Use of Energy Build Up to Identify the Most Critical Heeling Axis Direction for Stability Calculations for Floating Offshore Structures
For offshore structures like semi submersibles and jack-ups, hydrostatic stability is to be determined for what is called the weakest axis, which is not necessarily the same as the longitudinal axis of symmetry of the structure. When allowing trim to take place, the determination of the critical axis is complicated as free trimming leads to multiple solutions regarding the position for a given heel angle. It will be shown that for a freely floating structure, looking at the increase in potential energy can be used to identify those axis directions which are critical as well as realistic. The theoretical results will be illustrated with detailed data obtained for a two typical offshore structures using a standard stability program.
KeywordsAxis Direction Offshore Structure Stability Calculation Minimum Energy Path Semi Submersible
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