Modeling and experimental validation of axial drill string dynamics
msra(2009)
摘要
In the analysis of torsional stick-slip vibrations in drilling systems using drag bits, the drill string model is generally limited to the torsional dynamics. Herein, the bit-rock interaction is often modeled as a velocity-weakening friction law, which leads to torsional (stick-slip) vibrations. However, bit-rock interaction experiments using single cutters have not revealed any intrinsic velocity-weakening effect, suggesting that this effect is likely to be the result of complex drill string dynamics. This insight led to a different modeling approach, introduced in [3]. Here, the axial and torsional dynamics of the drill string are coupled via a rate-independent bit-rock contact model [1]. Analysis of this model shows that fast self-excited axial vibrations lead to an apparent velocity-weakening effect in the torsional direction [2], causing torsional vibrations and stick-slip. In this presentation, the focus will be on the experimental validation of the axial dynamics of the model as proposed in [3] and analyzed in [2].
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络