Dynamics of Drilling
Balakumar Balachandran
Mechanical Engineering, University of Maryland
ABSTRACT: From a mechanics standpoint, drilling for petro-chemicals is an inherently complex process. Models of this process are nonlinear in nature. For instance, sources of nonlinearities that can cause undesirable and harmful vibrations in drill-strings include contact between the drill string and bore hole, coupling between axial, torsional, and lateral motions, as well as those associated with the drag-bit cutting mechanics. The cutting action is a source of delay effects much like in a metal cutting operation such as milling. Balachandran discusses a combination, of analytical, numerical, and experimental results obtained on drill-string dynamics will be presented and the observed phenomena including forward and backward whirling motions and stick-slip dynamics.
