Stick–slip vibrations in oil well drillstring: A review

Multiple Mode Analysis of the Self-Excited Vibrations of Rotary Drilling Systems

This paper extends the approach proposed by Richard et al (2007) to analyze the axial and torsional vibrations of drilling systems that are excited by the particular boundary conditions at the drag bit-rock interface, by basing the formulation of the model on a continuum representation of the drillstring rather than on a characterization of the drilling structure by a two degree of freedom syst...

A Successful Experience in Optimization of a Production Well in a Southern Iranian Oil Field

Phonatory vibrations in singers. A critical review

Most Westem opera singers report feeling phonatory vibrations, i.e., vibrations caused by phonation, in different parts of their bodies while singing. As one perceives one's own voice quite differently from one's listeners, it has been hypothesized that phonatory vibrations may be useful as a feedback signal for the control of phonation. These vibrations have been examined in some articles whic...

Nonlinear Drillstring Dynamics Analysis

This paper studies the dynamical response of a rotary drilling system with a drag bit, using a lumped parameter model that takes into consideration the axial and torsional vibration modes of the bit. These vibrations are coupled through a bit-rock interaction law. At the bit-rock interface, the cutting process introduces a state-dependent delay, while the frictional process is responsible for d...

review of radiographic methods in dental implantology

چکیده ندارد.