ANALISIS GAYA FLUIDA PADA SILINDER DENGAN HELICAL RODS BER-GAP AKIBAT VARIASI RASIO GAP

Abstract

Vortex Induced Vibration (VIV) is one cause of damage due to fatigue on a cylindrical structure of offshore structure that are in the field of fluid flow (for example: riser, pipelines, mooring lines, etc.). VIV can lead to increase the fluid forces acting on the cylinder and furtherly causing fatigue. Its impact encouraged the researchers to discuss about passive control device. This paper specifically discusses one method to reduce fluid forces by installing the new type of passive control device on the cylinder which in this paper is called helical rods with gap. CFD simulation is a method used to obtain the fluid forces acting on the cylinder by using some variation of the gap ratio (g/D) that is 0.031, 0.092, 0.154, 0.215, and 0.277 at Reynolds number (Re) = 10 . The configuration with gap ratio g/D = 0.154 is the best configuration that can reduce the fluid forces. By installing the helical rods with gap, the simulation shown a reduction of drag and lift coefficient respectively for 11,34% and 88.32%.

Keywords : Vortex shedding, helical rods with gap, gap ratio, fluid forces