Abstract The dynamic response of the coiled tubing (CT)-in-riser system is critical to the success of offshore CT operations. The purpose of this work is to investigate the mechanical behavior of the CT and the riser and analyze the influencing factors of the coupled system. This paper builds dynamic models of the micro elements of the CT and the riser, and then a coupled model of the CT-in-riser system is presented considering the excitation of ocean loads and the coupling interaction between the inner pipe and the outer pipe. The dynamic coupled model is solved by the finite element method. A finite element model of the CT-in-riser system is built using the Abaqus/AQUA module. The effect of the operating parameters including the top injection force, the top tension, the platform offset, the annular clearance, and the friction coefficient, and the environmental parameters including the ocean depth, current speed, wave period, and wave height are discussed. The results show that the top tension should be properly controlled; the platform offset and friction coefficients should be reduced; the annular clearance should be appropriately reduced; a low current speed and wave height should be selected for operation; and the wave period and wave height have a little effect on the CT axial force. This research can provide important theoretical support for the offshore CT application.

中文翻译：

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考虑运行和环境参数的连续油管立管系统动力效应分析

摘要 连续油管 (CT) 立管系统的动态响应对海上 CT 作业的成功至关重要。这项工作的目的是研究 CT 和隔水管的力学行为并分析耦合系统的影响因素。本文建立了CT和立管微元件的动力学模型，然后提出了考虑海洋载荷激发和内管与外管耦合相互作用的CT-in-Riser系统耦合模型。动力耦合模型采用有限元法求解。立管内 CT 系统的有限元模型是使用 Abaqus/AQUA 模块构建的。顶部注射力、顶部张力、平台偏移、环形间隙和摩擦系数等操作参数的影响，讨论了海洋深度、水流速度、波浪周期和波浪高度等环境参数。结果表明，应适当控制顶部张力；应减少平台偏移和摩擦系数；应适当减小环形间隙；作业时应选择低水流速度和波高；波周期和波高对CT轴力影响不大。该研究可为海上CT应用提供重要的理论支持。作业时应选择低水流速度和波高；波周期和波高对CT轴力影响不大。该研究可为海上CT应用提供重要的理论支持。作业时应选择低水流速度和波高；波周期和波高对CT轴力影响不大。该研究可为海上CT应用提供重要的理论支持。