ABSTRACT

The wave and current coexist in the open sea. The existence of current in the water body changes the dynamic behavior of the sea wave and thus applies different hydrodynamic loading on the offshore structures. In this paper, the effect of the co-existence of wave and current in the water body is presented for both classic and truss spars. The purpose of this study is to suggest the better performing spar platform for the oil and gas operation to be installed in Malaysian offshore locations. In order to achieve the objective of this study, model tests have been done in the Universiti Teknologi PETRONAS Offshore Laboratory. The results are presented in terms of Response Amplitude Operator (RAO) for surge, heave, and pitch. The results show that the truss spar has lower responses compared to the classic spar and thus is preferable to be installed in the Malaysian offshore region where the current and wave act jointly.