eprintid: 10059163
rev_number: 17
eprint_status: archive
userid: 608
dir: disk0/10/05/91/63
datestamp: 2018-10-25 14:03:50
lastmod: 2020-02-12 16:23:19
status_changed: 2018-10-25 14:03:50
type: article
metadata_visibility: show
creators_name: Zhao, X
creators_name: Van Der Heijden, G
title: Dynamic torsional buckling: Prebuckling waves and delayed instability
ispublished: pub
divisions: UCL
divisions: A01
divisions: B04
divisions: C05
divisions: F44
keywords: Cosserat rod, torsional wave, torsional buckling, delay of buckling, corner singularity
note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: We study torsional buckling of a rod within the dynamics context, recognising that in a real experiment a twisting moment is not instantaneously applied and therefore an angular velocity (a spin) always accompanies a twist. We derive and solve the wave equation that governs prebuckling torsion dynamics and highlight the compatibility problem between initial and boundary conditions (corner singularity) plaguing numerical solution of the equation. We deal with this problem by introducing a smoothing function. Prebuckling torque oscillations are a major concern in various turbine applications.

Torsional instability, upon further increase of the applied moment, is found to be delayed by the dynamic loading. We determine the dependence of the critical load on the rate of application of the moment by computing initial postbuckling solutions and extrapolating back to the critical point. For these computations we use the geometrically-exact Cosserat rod equations, which we discretise with the generalised-α method. We argue that in addition to inertia a gyroscopic effect may play a role in the delay. Our results may help explain delayed torsional buckling recently observed in simulation studies of flexible marine risers.
date: 2019-04
date_type: published
publisher: Elsevier
official_url: https://doi.org/10.1016/j.cnsns.2018.09.017
oa_status: green
full_text_type: other
language: eng
primo: open
primo_central: open_green
article_type_text: Article
verified: verified_manual
elements_id: 1595686
doi: 10.1016/j.cnsns.2018.09.017
lyricists_name: Van Der Heijden, Gert
lyricists_id: GVANH52
actors_name: Van Der Heijden, Gert
actors_id: GVANH52
actors_role: owner
full_text_status: public
publication: Communications in Nonlinear Science and Numerical Simulation
volume: 69
pagerange: 360-369
issn: 1007-5704
citation:        Zhao, X;    Van Der Heijden, G;      (2019)    Dynamic torsional buckling: Prebuckling waves and delayed instability.                   Communications in Nonlinear Science and Numerical Simulation , 69    pp. 360-369.    10.1016/j.cnsns.2018.09.017 <https://doi.org/10.1016/j.cnsns.2018.09.017>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10059163/1/paper_subm.pdf