Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents
Scale effects must be considered when results of small-scale laboratory tests on scour below offshore pipelines are extrapolated to real-life situations. In the present study, a 2D Finite Element Method (FEM) numerical model for scour simulation was employed to evaluate scale effects in modelling sc...
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ftunivwestsyd:oai:researchdirect.westernsydney.edu.au:uws_27572 2023-05-15T14:23:08+02:00 Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents Zhao, Xu Zhao, Ming (R16667) Cheng, Liang Isshiki, H. (Editor) International Conference on Ocean, Offshore and Arctic Engineering (Event place) 2011 print 8 http://handle.uws.edu.au:8081/1959.7/562680 https://doi.org/10.1115/OMAE2011-49635 http://www.asmeconferences.org/omae2011/ eng eng U.S., ASME Proceedings of the ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering (OMAE 2011), June 19-24, 2011, Rotterdam, The Netherlands--9780791844397 pp: 931-938 090599 - Civil Engineering not elsewhere classified conference paper 2011 ftunivwestsyd https://doi.org/10.1115/OMAE2011-49635 2020-12-05T18:12:21Z Scale effects must be considered when results of small-scale laboratory tests on scour below offshore pipelines are extrapolated to real-life situations. In the present study, a 2D Finite Element Method (FEM) numerical model for scour simulation was employed to evaluate scale effects in modelling scour below a single pipeline subjected to steady currents. In the model, the Reynolds-Averaged Navier-Stokes (RANS) equations with a k-? turbulence closure are supplemented by a morphological model with both suspended load and bedload sediment transport rates included. Scour simulations were conducted at a number of scales with various Shields parameter values and sediments of two median grain sizes. The numerical results indicate that for the range of parameters investigated in this study, the normalized equilibrium scour depth below the pipe centre decreases in a linear fashion as the pipe diameter increases. Accordingly, an expression delineating scale-effect trends that relate deviations in normalized equilibrium scour depths to those in pipeline diameters is proposed, thereby contributing to an accurate extrapolation of small-scale model test results to prototype scale in modelling scour below pipelines in currents. Conference Object Arctic University of Western Sydney (UWS): Research Direct Volume 7: CFD and VIV; Offshore Geotechnics 931 938 |
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University of Western Sydney (UWS): Research Direct |
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ftunivwestsyd |
language |
English |
topic |
090599 - Civil Engineering not elsewhere classified |
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090599 - Civil Engineering not elsewhere classified Zhao, Xu Zhao, Ming (R16667) Cheng, Liang Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
topic_facet |
090599 - Civil Engineering not elsewhere classified |
description |
Scale effects must be considered when results of small-scale laboratory tests on scour below offshore pipelines are extrapolated to real-life situations. In the present study, a 2D Finite Element Method (FEM) numerical model for scour simulation was employed to evaluate scale effects in modelling scour below a single pipeline subjected to steady currents. In the model, the Reynolds-Averaged Navier-Stokes (RANS) equations with a k-? turbulence closure are supplemented by a morphological model with both suspended load and bedload sediment transport rates included. Scour simulations were conducted at a number of scales with various Shields parameter values and sediments of two median grain sizes. The numerical results indicate that for the range of parameters investigated in this study, the normalized equilibrium scour depth below the pipe centre decreases in a linear fashion as the pipe diameter increases. Accordingly, an expression delineating scale-effect trends that relate deviations in normalized equilibrium scour depths to those in pipeline diameters is proposed, thereby contributing to an accurate extrapolation of small-scale model test results to prototype scale in modelling scour below pipelines in currents. |
author2 |
Isshiki, H. (Editor) International Conference on Ocean, Offshore and Arctic Engineering (Event place) |
format |
Conference Object |
author |
Zhao, Xu Zhao, Ming (R16667) Cheng, Liang |
author_facet |
Zhao, Xu Zhao, Ming (R16667) Cheng, Liang |
author_sort |
Zhao, Xu |
title |
Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
title_short |
Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
title_full |
Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
title_fullStr |
Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
title_full_unstemmed |
Numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
title_sort |
numerical investigation of scale effects in modelling scour below offshore pipelines under steady currents |
publisher |
U.S., ASME |
publishDate |
2011 |
url |
http://handle.uws.edu.au:8081/1959.7/562680 https://doi.org/10.1115/OMAE2011-49635 http://www.asmeconferences.org/omae2011/ |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
Proceedings of the ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering (OMAE 2011), June 19-24, 2011, Rotterdam, The Netherlands--9780791844397 pp: 931-938 |
op_doi |
https://doi.org/10.1115/OMAE2011-49635 |
container_title |
Volume 7: CFD and VIV; Offshore Geotechnics |
container_start_page |
931 |
op_container_end_page |
938 |
_version_ |
1766295614016978944 |