Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Finite Element Modelling of Creep for an Industrial Application

Dissertation (MEng)--University of Pretoria, 2017.

Saved in:
Bibliographic Details
Other Authors: Inglis, Helen M.
Format: Thesis
Language:English
Published: University Of Pretoria 2017
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613680532717568
access_status_str Open Access
author2 Inglis, Helen M.
author_browse Inglis, Helen M.
author_facet Inglis, Helen M.
collection Thesis
dc_rights_str_mv © 2017 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MEng)--University of Pretoria, 2017.
format Thesis
id oai:repository.up.ac.za:2263/60133
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:39:59.869Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2017
publishDateRange 2017
publishDateSort 2017
publisher University Of Pretoria
publisherStr University Of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/60133 Finite Element Modelling of Creep for an Industrial Application Inglis, Helen M. Pietra, Francesco Howard, Gareth Johnathan Ansys Creep Finite Element Analysis Life Prediction NIMS Experimental Data UCTD Dissertation (MEng)--University of Pretoria, 2017. Thermal power stations operate at elevated temperatures and pressures in order to attain maximum available steam energy. At these high temperatures creep becomes a dominant mechanism that needs to be considered. However, for many components, the locations where peak stresses occur are unreachable to apply the commonly used Non-Destructive Testing (NDT) techniques. This encourages the use of Finite Element Analysis (FEA) to better predict the creep state in these complex components. Commonly, creep damage models are used in conjunction with accelerated creep tests to develop material models that can be implemented into a FEA to determine failure. These approaches are often infeasible for industrial decision-making, leaving a gap for more accessible commercially available models to be developed. This paper focuses on using openly available creep data from the Japanese National Institute for Material Science (NIMS). A creep strain model capable of modelling only the primary and secondary creep regimes was then chosen from the ANSYS database to fit this data. In order to fully characterise the experimental data a multi-creep-model approach was adopted that uses a family of creep models, instead of a single creep material model, to characterise the probable range of responses. This methodology was applied to an industrial application, namely an Intermediate Pressure (IP) valve operating under creep-prone conditions. The multi-creep-model approach was incorporated into FEA to analyse the variation in stress distributions. It was interesting to see that a variation of 153% in the creep strain models only resulted in a 21% variation in the relaxed stress. Worst case scenario life time calculations were then conducted using both a time-based Larson-Miller approach and a strain-based ASME code approach. Both sets of results showed that, for the specific component of interest, creep rupture lifetimes were in excess of 3000 years. It was therefore noted that, for the IP valve of interest, the operating temperature and pressure combination were such that no worrisome creep damage occurred. In conclusion, for the specific component analysed, the operating conditions are such that creep based failure will not occur. NRF EPPEI Mechanical and Aeronautical Engineering MEng Unrestricted 2017-05-02T05:35:49Z 2017-05-02T05:35:49Z 2017-04-26 2017 Dissertation Howard, GJ 2017, Finite Element Modelling of Creep for an Industrial Application, MEng Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/60133> A2017 http://hdl.handle.net/2263/60133 en © 2017 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University Of Pretoria
spellingShingle Ansys
Creep
Finite Element Analysis
Life Prediction
NIMS Experimental Data
UCTD
Finite Element Modelling of Creep for an Industrial Application
title Finite Element Modelling of Creep for an Industrial Application
title_full Finite Element Modelling of Creep for an Industrial Application
title_fullStr Finite Element Modelling of Creep for an Industrial Application
title_full_unstemmed Finite Element Modelling of Creep for an Industrial Application
title_short Finite Element Modelling of Creep for an Industrial Application
title_sort finite element modelling of creep for an industrial application
topic Ansys
Creep
Finite Element Analysis
Life Prediction
NIMS Experimental Data
UCTD
url http://hdl.handle.net/2263/60133