三类边界条件下隔水套管涡激非线性振动的分析研究

摘要

The casing pipes are widely used for drilling wells in the ocean.But less investigation on VIV excited by wave-current combination was done for casing pipes in the deep water.In this paper,the vortex-induced nonlinear vibration of casing pipes in deep water was studied considering the loads of current and combined wave-current.The vortex-induced vibration equation of casing pipes was set up with considering the beam mode and Morison's nonlinear fluid damp as well as the vortex-excited loads under three different boundary conditions.The vortex-excited nonlinear vibration was calculated by using Galerkin's method.The response including primary resonance induced by current and the composite resonance under combined wave-current for the marine drilling risers of the Donghai 3 were studied.The numerical results show that the dynamic response of marine risers induced by the current is basic and the influence of wave may be neglected.The vortex-induced nonlinear vibration of casing pipes under three different boundary conditions is studied and the complicated response behaviors of casing pipes are described under combined wave-current based on the numerical simulations.%考虑流及波流联合作用,研究了套管的涡激非线性振动.将套管简化为梁模型,考虑3类不同的边界条件,计及莫里森非线性流体动力和涡激荷载,建立套管的涡激振动方程.应用克雷洛夫函数求解套管的固有频率和模态,采用了计算涡激非线性动力响应的迦辽金方法.以东海勘探3号钻井隔水套管为例,研究了不同边界条件下流引起的主共振和波流联合引起的组合共振.计算结果表明:流对套管的动力响应占主导地位,而波的影响不大.分析了3类不同边界条件下隔水套管的涡激非线性动力响应,揭示了波流联合激励下套管复杂的动力响应特性.