| Drill-string failure is recognized by the drilling community as one of its most costly and frequently encountered problems. In order to diminish the frequency of such failures, the drilling community has been focusing on the modeling of the static and dynamic behaviors of drill-strings, towards increasing efficiency. Drill-string dynamics involves complex phenomena with excitations in axial, lateral and torsional directions, and coupling of these three and other factors such as mass imbalance, whirling, or stick-slip motion of the bit.;The present study focuses on one aspect which has not been studied in detail by the drilling community, namely the consideration of random loads on the BHA studied by a frequency domain approach. A comprehensive literature survey is attempted and elucidating numerical results are provided. |
