Development of a VIV observation method of rotating drill pipe using accelerometers

The marine drilling riser is used for various purposes today. Particularly, it is well known that Vortex Induced Vibration (VIV) occurs when a riser pipe is located under a flow. Therefore, many studies in VIV are conducted as the issue of representative fluid-structure vibration. We have also study about VIV, and investigated the behavior of a drill pipe model under various conditions in order to understand VIV properties in a drill pipe. As an observation method of this drill pipe model, we have ever obtained the displacement information of the drill pipe model with a stereo camera system. However, it takes time to obtain an analysis result in this method. Therefore it is inefficient to carry out various experiments to understand an observed phenomenon only in this analysis method. It was necessary to develop a new method that the displacement information of the drill pipe model was analyzed immediately to perform the experiment that changed various conditions (the uniform flow, the tension, rotating speed of a drill model) effectively. As that solution, we developed the analytical method using the acceleration sensor. In this paper, we discuss it about the new measurement method by the accelerometer.