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
Modelling of the track supports with elements over elastic foundation together with dynamic internal degrees of freedom
KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.ORCID iD: 0000-0001-5760-3919
2018 (English)In: Proceedings of ISMA 2018 - International Conference on Noise and Vibration Engineering and USD 2018 - International Conference on Uncertainty in Structural Dynamics2018, Pages 3255-326828th International Conference on Noise and Vibration Engineering, ISMA 2018 and 7th International Conference on Uncertainty in Structural Dynamics, USD 2018; Leuven; Belgium; 17 September 2018 through 19 September 2018 / [ed] W. Desmet, B. Pluymers, D. Moens, W. Rottiers, KU Leuven - Departement Werktuigkunde , 2018, p. 3255-3268Conference paper, Published paper (Refereed)
Abstract [en]

Formulation of the Timoshenko elements is improved with the use of internal degrees of freedom (iDOF) representing the local displacements, leading to a new finite element approach specially devoted to the numeric analysis of the track dynamics. The dynamic formulation of the local displacement is proved to correct the frequency content of the track model. Regarding time domain studies, this approach avoids the displacement underestimation and shear discontinuity between elements, which are sources of inaccuracies and irregular behaviour.  Those rail sections located above the supports are modelled with Timoshenko element over elastic foundation (TEEF), and the rest with conventional Timoshenko elements (TIM4). By using TEEF prompt disruption of the contact force at support surpassing is avoided, and the frequency response of the track around the `pinned-pinned' frequency is corrected. Moreover the TEEF formulation is extended in order to account for the sleeper pitch rotation, and evaluation of its influence over the track dynamics is performed. 

Place, publisher, year, edition, pages
KU Leuven - Departement Werktuigkunde , 2018. p. 3255-3268
National Category
Mechanical Engineering
Identifiers
URN: urn:nbn:se:kth:diva-244300Scopus ID: 2-s2.0-85060393553ISBN: 9789073802995 (print)OAI: oai:DiVA.org:kth-244300DiVA, id: diva2:1289623
Conference
Leuven; Belgium; 17 September 2018 through 19 September 2018
Note

QC 20190220

Available from: 2019-02-18 Created: 2019-02-18 Last updated: 2019-02-20Bibliographically approved
In thesis
1. Development of new techniques for the numerical modelling of railway track dynamics. Application to rolling noise assessment
Open this publication in new window or tab >>Development of new techniques for the numerical modelling of railway track dynamics. Application to rolling noise assessment
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The numerical modelling is widely employed for the prediction of the railway track dynamic behaviour, which is of utmost importance for the characterisation of the undesired medium-high frequency phenomena, such as corrugation, wheel-out-of-roundness and noise emission. This study is devoted to the improvement of railway track numerical modelling, the efficient resolution of the problem in the time domain and the assessment of rolling noise for different approaches of the track modelling.

Regarding the enhancement of the railway track numerical modelling, two main core ideas have led the development of this task. On the one hand, the rail modelling, and on the other hand, the characterisation of the finite length nature of track supports. The proposals of this work include two basic premises, accuracy and computational efficiency.

Firstly, the study makes use of Timoshenko beam theory for the numerical description of the rail. However, the conventional Timoshenko finite element involves drawbacks for the description of the rail dynamic behaviour and the calculation of the wheel-rail interaction in the time domain. These problems are addressed by improving the finite element formulation, which is based on the description of its local displacements.

Secondly, the versatility of numerical methods is exploited to develop a distributed model of support. It substitutes the usual concentrated model, which entails overestimation of the periodicity effects and disruption of the wheel-rail interaction in the time domain.

Thirdly, the advantages of the formulation of numerical models in the frequency domain are explored focusing on the ability to fairly describe the sleeper dynamics, the enhancement of the model boundaries and the realistic modelling of the track components dissipative behaviour. Moreover, the frequency domain response can be used to obtain the wheel-rail interaction in the time domain efficiently, by means of the moving Green's function.

Lastly, this work deals with the assessment of rolling noise, in which particular emphasis is made on the influence of track dynamics in the noise prediction. At this regard, a methodology is proposed to account for the track periodicity, load speed and finite length of supports.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2019. p. 158
Series
TRITA-SCI-FOU ; 2019:07
Keywords
Track modelling, Timoshenko element, local deformation, distributed supports, moving Green's functions, rolling noise
National Category
Applied Mechanics
Identifiers
urn:nbn:se:kth:diva-244379 (URN)978-91-7873-102-2 (ISBN)
Public defence
2019-03-15, Salón de Grados, Paseo Manuel Lardizábal, 13, San Sebastián, Spain, 11:00 (English)
Opponent
Supervisors
Note

QC 20190220

Available from: 2019-02-21 Created: 2019-02-20 Last updated: 2019-02-21Bibliographically approved

Open Access in DiVA

No full text in DiVA

Scopus

Authority records BETA

Blanco, BlasKari, Leif

Search in DiVA

By author/editor
Blanco, BlasKari, Leif
By organisation
Aeronautical and Vehicle Engineering
Mechanical Engineering

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
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