Inplace Model Test Result Correlation of Multi Column Floater (MCF): Drilling and Production Unit

This paper presents the comparison of model tests and numerical results of Multi Column Floater (MCF). MCF is a new drilling and production deep-draft semisubmersible platform developed by Horton Wison Deepwater in Houston. A vertically restrained well deck or Multi Riser Buoyancy Can (MRBC) configured in the center of the MCF is technology enabler for dry tree semisubmersible. The MRBC independently supports and tensions the production and drilling risers. The production risers may be a combination of dry tree risers and subsea tree tubing risers. Inplace model tests were carried out at the FORCE Technology basin during the period September-October, 2007 for the internal study. The test emphasis was to understand the physical behavior of MCF at model scale so that a thorough correlation study could be carried out. MCF mooring stiffness, riser stiffness, natural periods and mass properties of the model were closely matched with target full-scale properties. Guide loads and relative motions between MRBC and hull were measured to obtain model-scale behavior. A wide range of sea states and towing speeds were covered in the test programs. Detailed comparison summarizing the statistical quantities of interests as well as time series and spectral plots are included in this paper. RAO and free decay comparisons are also described.