해양 세장체 와유기진동 하중계수 실험 계획과 장치

Abstract

In order to construct data base of load coefficients, such as VIV drag coefficient and VIV lift coefficient, by measuring the vortex induced loads to marine slender structure, such as the riser, tendon and mooring, an experiment plan and experiment device were designed. The loads for VIV should be considered importantly in designing marine slender structure in the view points of fatigue strength. The outer diameter, relative speed and CF (Cross-Flow) direction frequency-amplitude of the marine slender structure model were chosen as experiment variables. (Reynolds number), (reduced velocity), natural frequency of experiment device and facilities, amplitude ratio and allowable power supply were considered as experiment conditions or constraints. The relative speed in the direction of IL (In-Line) would be realized by linear translational motion of carriage in basin. Excitation motion in the direction of CF would be performed by a experiment device which adopted Scotch-Yoke mechanism. The loads and phase lag to slender body model in the directions of IL and CF would be measured in two-axis FBG (Fiber Bragg Grating) load cell.