牙轮钻头动力学模型的建立与仿真分析

Dynamic model establishing and simulation analysis of roller cone bit

在牙轮钻头几何学、运动学和钻头与岩石互作用静力学模型的基础上，对钻进过程进行适当简化后，建立了牙轮钻头动力学模型，主要包括钻头纵向动力学模型、钻头横向动力学模型和钻头扭转振动模型。在建立钻头动力学模型的基础上，完成了牙轮钻头动力学仿真分析软件的设计，利用该软件实现了对牙轮钻头动力学仿真分析计算，并与静力学模型的仿真计算结果进行分析对比，得出了影响钻头、钻柱动力学性能的因素除与钻头结构、牙齿结构、岩石性质和钻井参数有关外，还与钻具结构和钻具的组合形式有较大关系等结论。

Based on the geometric and kinematic models of a roller cone bit and the rock-bit interaction model, by simplifying the drilling process, the dynamic models of the bit are established, including the longitudinal and lateral dynamic medels and torsional vibration model. Thereafter the computer software for dynamic simulation analysis of the bit is developed.By using this software, simulation analysis and computation of the bit is carried out, the result is compared with the result obtained from the static model, and it is concluded that, the factors influencing the dynamic performances of the bit and drillstring include the structures and combination patterns of drill tools besides the structures of the bit and bit teeth, rock nature and drilling parameters.