Hydrodynamic Analysis on Semi-Submersible Platform

As the population increases exponentially and demand for inexpensive energy sources
continue to raise, exploration and production for fossil fuel is rapidly growing. In order to
meet the demands, the exploration has taken one step further to the extreme deep sea.
Floating production platform design is a far more efficient and economical rather that
fixed production platform at this depth. One of the floating production platform designs
in use today is semi-submersible. Semi-submersible platforms have widely been
operating for the exploration and production of fossil fuel because of its ability to
withstand extreme wave loading, adaptation to wide range of water depth and its great
mobility. Research aims to study the effect of hydrodynamic coefficient on semisubmersible
platform. Analyses of wave forces by using Linear Airy Wave Theory were
conducted. Dynamic equations in time domain were analyzed. The random waves were
analyzed using Pierson-Moskowitz Spectrum. Forces acting on platform were analyzed
using Morrison equation. Surge, heave and pitch analysis were carried out by using
Motion-Response Spectrum. Parametric study on various hydrodynamic coefficients was
conducted. The result indicates that responses subjected to varying hydrodynamic
coefficient in Morrison's coefficient yield small effect of responses considering three
types of tubular members surface roughness (clean, semi-fouled and fouled). It is
reasonable to state that the design of a semi-submersible platform can be implemented at
any condition.