Abstract
Stick-slip and bit-bounce are dangerous dynamic phenomena encountered during rotary drilling of oil-wells, but their exact origins and interplay are far from obvious. In this paper, we consider a fully coupled two degrees-of-freedom model, which assumes a state-dependent time delay and a viscous damping for both the axial and torsional motions. Without making any asymptotic assumptions, we have conducted a detailed linear stability analysis of the resultant mathematical model, which is composed of two coupled delay differential equations. The main significance of our work lies in providing practically useful results, which are in the form of stability charts in the plane of drilling rates and rotary speeds.
| Original language | English |
|---|---|
| Pages (from-to) | 2575-2592 |
| Number of pages | 18 |
| Journal | Journal of Sound and Vibration |
| Volume | 332 |
| Issue number | 10 |
| Early online date | 8 Feb 2013 |
| DOIs | |
| Publication status | Published - 13 May 2013 |
Bibliographical note
AcknowledgmentsDr. Pankaj Wahi of IIT Kanpur is gratefully acknowledged for the technical discussions and suggestions on modelling aspects and stability analysis of delay differential equations.