滑动导向钻井技术是我国应用最为广泛的一种导向钻井技术。钻井过程是一个典型的大变形时变问题：大长细比钻柱在弯曲井眼中发生大变形、大位移和大转动，且与井壁间的接触面随钻进过程随时间扩展。传统的解析和有限元方法均难以准确而高效地分析这一过程。本文运用多体动力学方法，对滑动导向钻进过程进行了建模和仿真研究，主要工作包括：1.建立了钻井系统多体动力学模型和井眼延伸模型耦合的滑动导向钻井过程模型，并在多体动力学框架下实现了系统的钻进仿真。钻井过程包括钻柱在井眼中的运动和井眼在钻头破岩作用下向前延伸。将钻柱中的稳定器建模为刚体，将钻柱中其他组件建模为绝对节点坐标梁单元，建立大长细比钻柱的刚柔耦合多体动力学模型；依据螺杆钻具变形和受力特点，将螺杆钻具的旁通阀总成、防掉总成和马达总成建模为绝对节点坐标梁单元，将传动轴和钻头建模为刚体，钻头相对螺杆钻具的转动建模为钻头相对传动轴转动的角速度约束，建立螺杆钻具的简化的多体动力学模型；引入描述钻头破岩的三维钻速方程，建立描述井眼延伸的钻进模型；在此基础上，将游车和顶驱的运动建模为钢丝绳的长度变化和顶驱定子转子间的角速度约束，建立滑动导向钻井过程的钻柱动力学与井眼延伸耦合模型；提出了一种在滑动导向钻井过程仿真计算中根据钻头姿态和钻进历史修正井眼轨迹的井眼轨迹预测计算方法。2.利用所建立的滑动导向钻井过程模型，研究了螺杆钻具弯角和钻进参数对游车和顶驱的受力状态以及得到的井眼轨迹的影响。基于滑动导向钻井过程的多体动力学模型，仿真了不同螺杆钻具弯角大小、不同游车下放速度、游车下放速度以不同频率和幅值波动时大钩载荷和顶驱扭矩的大小，比较了得到的井眼轨迹的延伸方向；仿真了突然改变游车下放速度和扭转顶驱时钻柱的动力学响应，分析了这两个过程中大钩载荷、顶驱扭矩和工具面变化的情况，比较了改变游车下放速度和扭转顶驱两种方案调整工具面需要的时间长度，分析了改变游车下放速度和扭转顶驱对井眼轨迹的影响。3.建立了滑动导向钻井过程和反馈控制联合仿真平台，实现了一种滑动导向钻井过程反馈控制评估方法；以某滑动导向钻井系统反馈软件为例，进行了滑动导向钻井过程反馈控制仿真，验证了反馈控制评估方法的可行性。

The slide directional drilling technique is the most widely used directional drilling technique in China. In the slide directional drilling process, there are complex large-scale stochastic contacts between the large-slenderness-ratio drill string and the wellbore. The wellbore, which is a contact surface, extends in the drilling process, so the wellbore is an time variable contact surface. At the same time, the drill string undergoes large deformation, large displacement, and large rotation in the curved wellbore. All these problems makes it difficult to precisely and efficiently model and simulate the slide drilling process with the conventional analytical methods or finite element method. In this thesis, the multibody dynamics method is applied to model and simulate the slide drilling process. The main work includes:1. A full hole drill string multibody dynamics system and drilling process coupled dynamical model is established, and the drilling process simulation of the system is realized under the multibody dynamics framework. The drilling process includes the motion of the drill string inside the wellbore and the wellbore extension under the rock penetration process of the bit. The stabilizers in the drill string are modeled as rigid bodies. Other parts of the drill string are modeled as absolute nodal coordinate formulation beam element. Thus a rigid-flexible coupled multibody dynamics model is established for the large-slenderness-ratio drill string. Based on the load and deformation of the positive displacement motor, a simplified rigid-flexible coupled multibody dynamics model of the positive displacement motor is established. The bypass valve, the rotor catch system and the motor section of the positive displacement motor are modeled as an absolute nodal coordinate formulation beam element. The shaft and the bit are modeled as two rigid bodies. The rotation between the bit and the positive displacement motor is modeled as the angular velocity constraint between the bit and the shaft. The three-dimensional drilling velocity equation is introduced, and a drilling model is established to describe the wellbore extension process. The motion of the traveling block is modeled as the length change in the drill line, and the rotation of the topdrive is modeled as the angular velocity constraint between the rotor and stator of the topdrive. Based on these works, the coupled model of the drill string dynamics and the wellbore extension for the slide directional drilling process is established. A well trajectory prediction algorithm is developed, which adjusts the well trajectory according to the bit attitude and the drilling history during the simulation of the slide directional drilling process.2. Applying the established slide drilling process model, the impacts of the positive displacement motor bent angle and the drilling parameters on the hook load and surface torque and on the well trajectory are analyzed. Based on the multibody dynamics model of the slide directional drilling process, the hook load and surface torque are simulated under different positive displacement motor bent angle, different traveling block decent rate, traveling block decent rate with different fluctuation frequency and amplitude. The well trajectory extending direction is compared. The dynamical response of the drill string after changes in the traveling block decent rate or after turns in the topdrive. The hook load, the surface torque, and the toolface are analyzed in these two processes. The time consumed to adjust the toolface is compared between the two plans, which are changing the traveling block decent rate and rotating the topdrive. The impact of these two plans on the well trajectory is also analyzed.3. A slide directional drilling process and feedback control joint simulation platform is established. A slide directional drilling process feedback control evaluation method is realized. As an example, the slide directional drilling process feedback control simulation is preformed on a slide directional drilling process feedback control software. This verifies the feasibility of the feedback control evaluation method.