Experiment with a Vertical Pipe in a Water Tank

Ahmad Taha¹; Caio Cesar de Oliveira Trigo¹; Celso Kazuyuki Morooka¹

¹ Unicamp

doi:10.20906/CPS/CILAMCE2015-0541

Resumo

The main aim of the present work is to study the dynamic response behavior of a vertical pipe in a still water tank. The vertical pipe has the bottom termination free and the top termination is forced to move by a motion device with a motor. Displacements along the pipe length are measured and vibration of the pipe is analyzed. Vertical pipes are commonly used for different offshore petroleum applications, such as petroleum wellbore drilling and sometimes to provide cold water from the ocean for cooling operations of the petroleum process plant in floating platforms and ships. Imposed motions at the top of the vertical pipe intend to represent motions coming from the surface vessel due to waves, sea current and wind. Results obtained from the experiment allowed better understanding of the pipe behavior and to investigate numerical simulation procedures by the use of a commercial software (Orcaflex©). In the present work, a physical model with small pipe diameter has been developed for the laboratory experiment, and optical measurement system for pipe displacements in a still water tank with imposed motions on the pipe top termination was developed. Experiment is described in details and comparative analysis among numerical simulations and experiment is carried out. The proposed numerical simulation approaches as well as experimental measurement procedures have shown very promising results to evaluate the behavior of a vertical pipe in water.

Palavras-chave: Offshore structure - hydrodynamic; Rigid Riser; Water tank experiment