Yong Wang, Hongjian Ni*, Ruihe Wang, Shubin Liu
FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.5, pp. 1263-1273, 2022, DOI:10.32604/fdmp.2022.020405
- 27 May 2022
Abstract A specific model is elaborated for stick-slip and bit-bounce vibrations, which are dangerous dynamic phenomena
typically encountered in the context of rotary drilling applications. Such a model takes into account two coupled
degrees of freedom of drill-string vibrations. Moreover, it assumes a state-dependent time delay and a viscous
damping for both the axial and torsional vibrations and relies on a sawtooth function to account for the cutting
force fluctuation. In the frame of this theoretical approach, the influence of rock brittleness on the stability of the
drill string is calculated via direct integration of the More >