Research Article
Nonlinear Model and Qualitative Analysis for Coupled Axial/Torsional Vibrations of Drill String
Figure 9
Period responses of the system ().
(a) Phase diagram of the axial modal |
(b) Oscillogram of the axial modal |
(c) Phase diagram of the torsional modal |
(d) Oscillogram of the torsional modal |
(e) Three-dimensional phase diagram |
(f) Poincare section |