Experimental study on the vibration characteristics of fluid–structure coupling in the transition process of flexible bending pipes

Abstract

The flexible bending pipes with large aspect ratios are more likely to cause large vibrations in the extraction of offshore oil and gas resources, which can accelerate the fatigue damage of the pipes. In order to explore the characteristics of fluid–structure coupling vibration during the transition period after the flexible bending pipe starts to transport fluid, an experimental platform of flexible bending pipes fluid–structure coupling vibration was created. The strain and vibration displacements of the pipe were measured by a resistance strain gauge and a high-speed camera system, respectively. According to the measure results, the largest values of stress and strain both were discovered at the pipe's two ends, and the maximum values of vibration displacement and vibration velocity were found in the middle of the pipe. The phenomenon indicates that the two ends of the pipe are more prone to fatigue damage. Moreover, the dynamic response and dynamic characteristics of the pipeline during the transition process were investigated. In addition, the effects of fluid flow rate, pipe wall thickness and different pipes on the dynamic response and dynamic characteristics of the pipe were also investigated in the present work.