超深井侧钻水平井是在非常规油气资源高效挖潜过程中被广泛应用的井型，其狭窄的空间尺寸与水平的空间方位易使钻柱与井壁发生动态接触，进而对钻柱的动力学行为造成影响。针对上述工程问题，通过对钻柱与井壁接触点处的钻柱运动与力学特征进行分析，构建了超深井侧钻水平井钻柱动力学模型，并通过物理实验对模型的仿真结果进行了可靠性验证。其次，基于实际钻井案例，利用所构建的模型依次对钻头的三维位移、三维速度分布、钻柱的三维载荷分布与转速对钻柱振动的影响进行了仿真分析。研究结果表明：与传统钻柱动力学模型相比，在考虑了钻柱与井壁之间动态接触特征之后所构建的模型，更加符合超深侧钻水平井的钻具安全分析与井眼轨迹控制需求；在侧钻水平井钻井作业过程中，钻头的横向振动会呈现出显著的谐波状态，且这种振动状态会使钻柱产生较大幅度的纵向位移；钻柱的横向与纵向振动存在着耦合响应关系，其纵向振动会通过增大自身曲率的方式加剧横向振动幅度；钻柱的振动载荷主要集中在下部结构，且在向上传播过程中的衰减速度较快；当侧钻水平井钻井作业的转速处于195.00 ~ 210.00 r/min与100.00 ~ 140.00 r/min两个区间内时，易引发钻头损坏、井眼扩大与钻柱断裂等问题，因此在实际钻井作业中应对这两个转速区间进行规避。

Ultra-deep sidetracked horizontal wells are widely used in the efficient exploitation process of unconventional oil and gas resources. Their narrow spatial dimensions and horizontal spatial orientation easily lead to dynamic contact between the drill string and the wellbore, thereby affecting the dynamic behavior of the drill string. In response to the aforementioned engineering issues, by analyzing the motion and mechanical characteristics of the drill string at the contact point with the wellbore, a dynamic model of the drill string for ultra-deep sidetracked horizontal wells was built, and the reliability of the model's simulation results was verified through physical experiments. Secondly, based on actual drilling cases, the constructed model was used to simulate and analyze the three-dimensional displacement of the drill bit, the three-dimensional velocity distribution, the three-dimensional load distribution of the drill string, and the impact of rotation speed on the vibration of the drill string. The research results Show as follows. Compared to traditional drill string dynamics models, the newly developed model incorporating dynamic contact characteristics between the drill string and wellbore better aligns with the requirements for drill tool safety analysis and wellbore trajectory control in ultra-deep sidetracking horizontal wells. During the drilling operation of the sidetracked horizontal well, the transverse vibration of the drill bit exhibits a significant harmonic state, and this vibration state causes the drill string to undergo a larger longitudinal displacement. There is a coupled response relationship between the transverse and longitudinal vibrations of the drill string, with the longitudinal vibration intensifying the transverse vibration amplitude by increasing its own curvature. The vibration loads of the drill string are mainly concentrated in the lower structure and decay rapidly during propagation upwards. Rotational speeds within the ranges of 195.00 ~210.00 r/min and 100.00 ~ 140.00 r/min during sidetracking horizontal well drilling operations are prone to cause bit damage, wellbore enlargement, and drill string fracture, thus requiring avoidance in practical applications.