Modelling and Analysis of Stick-slip Behaviour in a Drillstring under Dry Friction
نویسندگان
چکیده
Stick-slip vibrations present at the bottom hole assembly (BHA) of a generic oilwell drillstring subject to dry friction are studied. Different nonlinear differential equations-based models of a drillstring are analyzed. The drillstring models presented are oriented to avoid simulation problems due to the discontinuities originated by the presence of dry friction. The influence of different drilling parameters on the stick-slip behaviour are studied and relations between them are established to briefly state some control methodologies for drilling operation.
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