Dynamic Response Analysis Of Riser

With the development of the global deep-water oil, the research of drilling riser in deep water fields is carried out step by step. Theory of riser in shallow water is relatively mature and perfect, but there is still much shortage in deep water, need to be further improved. Under such research background, this paper integrates simulation environment in use of ANSYS CFX 11.0 ANSYS software and ANSYS Workbench and studies currents flow and flow field assuming that the riser is rigid, then analyses Fluid-structure interaction in the ocean currents, waves and currents and waves mixed flow field assuming the riser is flexible, so a new way is explored to study deep water riser. The study find the riser is impacted obviously when the current flow through the riser, then vortex shedding is formed. The growth of vortex is not effected by upper and lower water, but the velocity of the current near the riser is increased effected by upper and lower water. When the wave flow through the riser, the riser is impacted by periodic wave at the same time. Through analysis of law of motion of flexible riser in flow field and fluid-structure interaction, find that the movement is consistent in the ocean flow field, only that the maximum displacement of various depths is different. The movement and deformation of riser in the marine environment is mainly affected by two parts:one is the impact effect ,the other is the role of vortex-induced vibration in the flow field near the riser.