大长径比钻柱非线性动力学研究进展与展望

Research progress and prospects in nonlinear dynamics of drillstring with high slenderness ratio

摘要:

钻柱长径比超过50000时呈现高度柔性与显著非线性特征，轴向、横向、扭转振动相互耦合，易引发黏滑、涡动、参数共振等问题，严重影响特深井钻井安全与钻进效率。本文围绕大长径比钻柱极端几何特征引发的动力学难题，系统梳理其非线性振动特性、动力学建模方法、振动控制策略及工程应用挑战。研究表明，轴向、横向与扭转振动之间存在几何非线性耦合、边界非线性耦合及摩擦耦合，诱发正反向涡动共存、黏滑多稳态等复杂现象；有限元法与几何精确梁理论侧重高保真刻画，但计算开销高昂；模型降阶与数据驱动方法提升了计算效率，却需谨慎处理对波传播效应的简化；实验验证是检验模型的关键，但缩尺外推修正仍是难题。当前研究在理论层面仍面临多模态能量传递机理、状态依赖时滞动力学、非光滑系统分岔理论三大科学问题，在工程层面亟需攻克全井段高效预测、极限延伸动态评估等核心难题，该领域未来将向多物理场耦合、随机可靠性分析、数据驱动与数字孪生相融合的智能动力学方向发展，为提升超深层地质资源开发的安全性和经济性提供更坚实的科学支撑。

Abstract:

When the slenderness ratio （L/D） of a drillstring exceeds 50000， it exhibits high flexibility and pronounced nonlinear characteristics. The coupled axial， lateral， and torsional vibrations easily induce issues such as stick-slip， whirling， and parametric resonance， severely compromising the drilling safety and efficiency of ultra-deep wells. Focusing on the dynamic challenges induced by the extreme geometric features of high-slenderness-ratio drillstrings， this paper systematically reviews their nonlinear vibration characteristics， dynamic modeling methods， vibration control strategies， and engineering application challenges. The review indicates that geometric， boundary， and friction nonlinear couplings exist among the axial， lateral， and torsional vibrations， inducing complex phenomena such as the coexistence of forward and backward whirling and stick-slip multi-stability； the finite element method and geometrically exact beam theory prioritize high-fidelity characterization but incur high computational costs； model order reduction and data-driven methods improve computational efficiency， yet the simplification of wave propagation effects requires careful handling； experimental validation is key to model verification， but extrapolation from scaled models to full-scale conditions remains challenging. Currently， research still faces three major scientific problems at the theoretical level： multi-modal energy transfer mechanisms， state-dependent time-delay dynamics， and bifurcation theory of non-smooth systems. At the engineering level， it is urgent to overcome core difficulties such as efficient full-wellbore prediction and dynamic evaluation of extended-reach limits. In the future， this field will evolve towards intelligent dynamics integrating multi-physics coupling， stochastic reliability analysis， data-driven approaches， and digital twins， providing solid scientific support for enhancing the safety and economic performance of ultra-deep geological resource development.