Dynamics of a distributed drill string system

Characteristic parameters and stability maps

Journal Article (2018)
Author(s)

Ulf Jakob F. Aarsnes (International Research Institute of Stavanger, DrillWell-Drilling and Well Centre for Improved Recovery)

Nathan van de van de Wouw (Eindhoven University of Technology, University of Minnesota, TU Delft - Team Bart De Schutter)

Research Group
Team Bart De Schutter
DOI related publication
https://doi.org/10.1016/j.jsv.2017.12.002
More Info
expand_more
Publication Year
2018
Language
English
Research Group
Team Bart De Schutter
Volume number
417
Pages (from-to)
376-412

Abstract

This paper involves the dynamic (stability) analysis of distributed drill-string systems. A minimal set of parameters characterizing the linearized, axial-torsional dynamics of a distributed drill string coupled through the bit-rock interaction is derived. This is found to correspond to five parameters for a simple drill string and eight parameters for a two-sectioned drill-string (e.g., corresponding to the pipe and collar sections of a drilling system). These dynamic characterizations are used to plot the inverse gain margin of the system, parametrized in the non-dimensional parameters, effectively creating a stability map covering the full range of realistic physical parameters. This analysis reveals a complex spectrum of dynamics not evident in stability analysis with lumped models, thus indicating the importance of analysis using distributed models. Moreover, it reveals trends concerning stability properties depending on key system parameters useful in the context of system and control design aiming at the mitigation of vibrations.

No files available

Metadata only record. There are no files for this record.