Nonlinear Dynamic Analysis of Drilling Fluid in Drilling Riser

In recent years,the offshore oil exploration and exploitation are being approached from shallow water to deepwater,even to the ultra-deepwater.As the water depth increases,the force acting on the drilling riser becomes more and more complicated and higher strength and stability are requested.Effects of top tension ratio(TTR),the length of the riser and buoyancy modules on natural frequency were studied numerically.Approaches to avoiding resonance of the deepwater drilling riser are put forward.And the results can be referred in designing and using of deep water drilling riser.