Feasibility analysis of deep steep riser based on co-rotational coordinate method

Abstract

DSR (Deep steep riser) is a new riser structure that reduces the ultra-high-tension load caused by the riser self-weight. In this paper, the mechanical behavior of DSR under different buoyancy module configurations and different ocean currents is studied. The finite element model of DSR is established based on co-rotational coordinate method. The model is solved by arc length method. The accuracy of the numerical method is verified by Abaqus software. Then, the effects of buoyancy module length and buoyancy factor on DSR are analyzed. Finally, the influence of different current incidence angles and velocities on DSR is evaluated. The results show that the DSR model based on the co-rotational coordinate method can effectively simulate the nonlinear behavior of large deformation of DSR. The method is simple, flexible and computationally efficient. This method can quickly improve the efficiency of numerical calculation in static analysis of deepwater riser. And DSR is feasible under certain conditions.