FLEXIBLE TUBES UNDER THE ACTION OF EXTERNAL AND INTERNAL FLOWS: A THEORETICAL-EXPERIMENTAL INVESTIGATION

Abstract

In the context of oil exploration, flexible pipes (risers) are often used to capture deep water, which is generally colder than the surface, to be used to cool the plant, improving its energy efficiency. These pipes are subject to wave action, platform/ship movements and internal water flow, making their dynamics extremely complex and non-linear. In order to gain a better understanding of these dynamics, this research project aims to continue the research project carried out during the doctoral studies of Dr. Wagner Antonio Defensor Filho, under the supervision of Prof. Dr. Celso P. Pesce, which aimed to experimentally investigate crimped flexible pipes, with internal flow and eventually under external flow, and therefore subject to vortex-induced vibrations (VIV). Its main objective was to build a solid base of experimental data that would serve as a paradigmatic source for computational models involving these fluid-structure interaction phenomena, including those under development at the Offshore Mechanics Laboratory at USP's Polytechnic School. The study made it possible to carry out unprecedented experiments on test tanks, and fostered the development of low-order computer models and their comparison with high-order computer models (FEM).This research project aims to continue the experimental analysis of this vast database and to improve the computational models computational models developed, particularly by exploring the representation of the large amplitude responses in the supercritical regime, which occur in long flexible hoses in the unloading that have been observed and measured experimentally.