To compensate for the uncertainties, a number of simplified assumptions have been used to present the data in a user friendly and conservative manner for current and mooring line damping.
Although a significant investigation has been carried out in this study for current damping and mooring line damping, uncertainties still exist because of the complexity of the issues and lack of physical data for verification. Low frequency damping study: LF damping has many components, and each component is a complicated issue. The study provides guidance to designers on the selection of analysis methods and also provides data for API to develop guidance on analysis methods in future revision of API RP 2SK. The second study compares mooring analysis results from six analysis methods allowed by API RP 2SK for MODU moorings and investigates the relative conservatism among the six methods. The purpose of the study is to develop understanding and practical guidance for LF damping. The first study used frequency domain coupled analysis software, which was first benchmarked against damping research results, to generate low frequency (LF) damping estimates for a number of representative MODUs and moorings under various environmental conditions. This paper summarizes two studies conducted for the MODU Mooring Strength and Reliability JIP for improving the accuracy of mooring analysis. Inaccurate mooring analysis may lead to wrong conclusion concerning the acceptability of a MODU for a specific operation. As higher environmental criteria are now required for GOM MODU mooring operations, the accuracy of the mooring analysis for site assessment becomes more critical.