Experimental Investigation of Hydrodynamic Coefficients for Short-Crested Waves

Objectives: To determine the hydrodynamic coefficients; drag (Cd) and inertia (Cm), for short-crested waves exerted on vertical cylinder. Methods/Statistical Analysis: An experimental study on hydrodynamic coefficients of the top-fitted vertical cylinder subjected to short-crested waves is presented. The model tests were carried out in the wave tank of Offshore Laboratory of University Technology PETRONAS, Malaysia. In this study, the model testwas conducted by using two sets of vertical cylinder with diameter, 16 mm and 48 mm, which were subjected to four series of short-crested waves based on four different locations in Malaysian offshore region.The wave forces acting on the cylinder were recorded by using wave force sensor. The post processing data was carried outby considering The Least Square Method. The results were compared with the existing recommended hydrodynamic coefficients in the PETRONAS Technical Standard (PTS). Findings: The hydrodynamic coefficients for short-crested wave of a vertical cylinderwere obtained. The results showed that the experimental hydrodynamic coefficient values are 30 % to 45 % lowerthan the recommended hydrodynamic coefficients adopted by PTS. Application/Improvements: The hydrodynamic coefficients values obtained from this experimental investigationhave ensured the possibility of designing an economical and optimum design of offshore platforms could be achieved.