Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Inconsistency errors of constant velocity multi-time step integration algorithms
Luleå tekniska universitet.
2001 (English)In: Computer Assisted Mechanics and Engineering Sciences, ISSN 1232-308X, Vol. 8, no 1, p. 121-139Article in journal (Refereed) Published
Abstract [en]

Previously known multi-time step integration methods for finite element computations in structural dynamics have been shown to be unstable due to interpolation error propagation. New algorithms of multi-time step integration based on constant velocity during subcycling are investigated. The assumption of constant velocity gives linear variation of displacements so the errors connected to interpolation at the interface between different time step partitions are eliminated. As a consequence, the new constant velocity algorithms give bounded solutions and have been shown to be conditionally stable by their authors. However, numerical investigation demonstrates that if time steps close to the stability limit are used, the errors for higher natural modes are so huge that the obtained solutions can only be considered as incorrect. The main reason for this behaviour is that the constant velocity time integration algorithms are inconsistent. Displacements can be calculated either by direct integration or from the equation of motion leading to different solutions. Based on the numerical results it is concluded that use of time steps below stability limit is insufficient to assure proper solutions. Therefore, significant time step reductions are often required to assure acceptable error levels. As a consequence, the new subcycling algorithms can be more expensive than ordinary time integration. Because they also lead to larger errors the constant velocity subcycling algorithms are useless from practical point of view. Since subcycling is available as an option in LS-DYNA a serious warning is issued to potential users.

Place, publisher, year, edition, pages
2001. Vol. 8, no 1, p. 121-139
National Category
Infrastructure Engineering
Research subject
Structural Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-10168Local ID: 8ed7a1d0-0b92-11dd-9b51-000ea68e967bOAI: oai:DiVA.org:ltu-10168DiVA, id: diva2:983108
Note
Godkänd; 2001; 20080416 (cira)Available from: 2016-09-29 Created: 2016-09-29Bibliographically approved

Open Access in DiVA

No full text in DiVA

Infrastructure Engineering

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 51 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf