The Simulation Research Of Riser Transverse Vibration Characteristics

Deepwater drilling riser is one of the most important links in the ocean drillingplatform equipments, it is also one of the weakest and the most delicate components. Withthe exhaustion of the continental petroleum resources of oil and gas, drilling develop intothe ocean field gradually.The force environment of deepwater drilling riser is complex andprone to failure, so the force and the dynamic response of the deepwater riser hasimportant theoretical and practical significance. This paper will mainly carry out thefollowing aspects:Apply computer drawing software established the riser two-dimensional andthree-dimensional entity model. Analyze riser environment load.Simplify the risermechanical model.Establish mathematical model for lateral vibration of Marine riser andthe finite difference method to solve the model and acquire displacement and bendingmoment responses.Considering the internal fluid flow, the fluctuation of the rotation of the flexible jointstiffness, the buoyancy influence,the axial tension force produced by the gravity andbuoyancy effect is processed as a distribution force. Establish riser statics finite elementmodel. the natural frequency and vibration model are obtained by flexibility coefficientmethod. And analyzes the various factors on the influence of natural frequency andvibration mode.The nonlinear exciting force produced by ocean current and wave is linearized.withthe application of modal superposition method, riser dynamic response are obtained.With the using of Visual Basic6.0and Matlab programming, the deepwater riserdynamics simulation software is developed. We can get the natural frequency of the risertransverse vibration, vibration displacement and bending moment by using the software.Provide the basis for riser design and construction.