Effect of Hydrodynamic Force Coefficients on the Wave Forces on Jacket Platform

The evaluation of accurate hydrodynamic forces on a clean tubular member is the fundamental criteria in designing offshore structures. For the analysis and design of general jacket platforms, engineering consultants use Morison equation for wave forces are calculated based on the drag (CD) and inertia (CM) coefficients. The hydrodynamic coefficients used by consultants are constant or recommended values, even though the CD and CM are varying force coefficients that depend on Keulegan Carpenter number (KC) and Reynolds number (Re). This report provides a preliminary comparison of the maximum total force of jacket platforms on the various locations in Malaysian offshore regimes. The numerical analysis was done using Microsoft Excel by utilizing the existing wave parameters recorded in Petronas Technical Standard (PTS). The experimental data are derived from 1:70 scale model tests for the hydrodynamic total force acting on model tubes conducted in a wave tank. Structural Analysis Computer System (SACS) was used for verification and comparison of the numerical and experimental data to analyze the relevance of the data collected.