A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Fundamental Principles of Drill-String Mechanics and Their Qualitative Simulation
AbstractIn general mechanics, systems must follow the mechanical equilibrium principle, the minimum potential energy principle, and the minimum dissipation power principle. This paper confirms that a rotating drill string in a wellbore follows these three principles. The study presents three main findings. (1) As the rotary speed of a rod string increases, its deflection decreases nearer to the borehole center. (2) There exists a whirl-state transition critical rotary speed. If the rotary speed is below this critical rotary speed, the dissipation power increases as the rotary speed increases. If the rotary speed is higher than this critical rotary speed, the dissipation power first decreases rapidly as the rotary speed increases and the deflection of the rod string abruptly decreases, and then the dissipation power increases as the rotary speed increases. (3) As the viscosity of the liquid increases, the whirl-state transition critical rotary speed decreases. As the axial load increases, the whirl-state transition critical rotary speed decreases.
Fundamental Principles of Drill-String Mechanics and Their Qualitative Simulation
AbstractIn general mechanics, systems must follow the mechanical equilibrium principle, the minimum potential energy principle, and the minimum dissipation power principle. This paper confirms that a rotating drill string in a wellbore follows these three principles. The study presents three main findings. (1) As the rotary speed of a rod string increases, its deflection decreases nearer to the borehole center. (2) There exists a whirl-state transition critical rotary speed. If the rotary speed is below this critical rotary speed, the dissipation power increases as the rotary speed increases. If the rotary speed is higher than this critical rotary speed, the dissipation power first decreases rapidly as the rotary speed increases and the deflection of the rod string abruptly decreases, and then the dissipation power increases as the rotary speed increases. (3) As the viscosity of the liquid increases, the whirl-state transition critical rotary speed decreases. As the axial load increases, the whirl-state transition critical rotary speed decreases.
Fundamental Principles of Drill-String Mechanics and Their Qualitative Simulation
Xie, Jian (author) / Li, Zifeng / Tian, Weichao / Wang, Changjin
2017
Article (Journal)
English
Fundamental Principles of Drill-String Mechanics and Their Qualitative Simulation
| Online Contents | 2017
Analysis on Mechanics and Reliability of Drill String during Deep Drilling
| British Library Conference Proceedings | 2011
Some fundamental principles of soil mechanics
| Engineering Index Backfile | 1942