Calibration of Shiono and Knight Model to Estimate Shear Stress for Trapezoidal Channel
Aim of this study is to calibrate Shiono and Knight model for better determination of shear and velocity distribution in trapezoidal open channels. To do this, correct estimation of friction factor (<em>f)</em>, secondary current (Γ), and eddy viscosity (λ) is proposed as key affecting p...
| Main Authors: | , |
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| Format: | Article |
| Language: | fas |
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Shahid Chamran University of Ahvaz
2016-01-01
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| Series: | علوم و مهندسی آبیاری |
| Subjects: | |
| Online Access: | http://jise.scu.ac.ir/article_11805_88daad92a2b85e052f754f7879c66580.pdf |
| _version_ | 1818684516285284352 |
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| author | Babak Lashkar Ara Iran Dokht Dehghani |
| author_facet | Babak Lashkar Ara Iran Dokht Dehghani |
| author_sort | Babak Lashkar Ara |
| collection | DOAJ |
| description | Aim of this study is to calibrate Shiono and Knight model for better determination of shear and velocity distribution in trapezoidal open channels. To do this, correct estimation of friction factor (<em>f)</em>, secondary current (Γ), and eddy viscosity (λ) is proposed as key affecting parameters. Available data in literature are used to optimize these three parameters. Using channel aspect ratio <em>P<sub>b</sub>/P<sub>w</sub></em>, the channel subsections are selected. Non-dominated Sorting Genetic Algorithm is used to optimize the parameters and estimate shear and velocity distribution for each subsection. Results reveal that effects of friction factor and eddy viscosity are significant for aspect ratios of less than 2 and 6, respectively. Rate of change of the parameters with the aspect ratio show a considerable increase for aspect ratios of less than 4. In oppose to the literature for suggestion of a constant eddy viscosity of 0.67, calibration of the Shiono and Knight model in this study showed a variable eddy viscosity for variable flow conditions. Comparison of the model and experimental results confirms correct estimation of the aforementioned parameters. <br /> |
| first_indexed | 2024-12-17T10:51:52Z |
| format | Article |
| id | doaj.art-f67b79755b224d7bb1b67e95dd7fba92 |
| institution | Directory Open Access Journal |
| issn | 2588-5952 2588-5960 |
| language | fas |
| last_indexed | 2024-12-17T10:51:52Z |
| publishDate | 2016-01-01 |
| publisher | Shahid Chamran University of Ahvaz |
| record_format | Article |
| series | علوم و مهندسی آبیاری |
| spelling | doaj.art-f67b79755b224d7bb1b67e95dd7fba922022-12-21T21:51:57ZfasShahid Chamran University of Ahvazعلوم و مهندسی آبیاری2588-59522588-59602016-01-0138418920110.22055/jise.2016.1180511805Calibration of Shiono and Knight Model to Estimate Shear Stress for Trapezoidal ChannelBabak Lashkar Ara0Iran Dokht Dehghani1استادیار گروه مهندسی عمران دانشگاه صنعتی جندی شاپور دزفولدانشجوی دوره کارشناسی ارشد مهندسی عمران دانشگاه صنعتی جندی شاپور دزفولAim of this study is to calibrate Shiono and Knight model for better determination of shear and velocity distribution in trapezoidal open channels. To do this, correct estimation of friction factor (<em>f)</em>, secondary current (Γ), and eddy viscosity (λ) is proposed as key affecting parameters. Available data in literature are used to optimize these three parameters. Using channel aspect ratio <em>P<sub>b</sub>/P<sub>w</sub></em>, the channel subsections are selected. Non-dominated Sorting Genetic Algorithm is used to optimize the parameters and estimate shear and velocity distribution for each subsection. Results reveal that effects of friction factor and eddy viscosity are significant for aspect ratios of less than 2 and 6, respectively. Rate of change of the parameters with the aspect ratio show a considerable increase for aspect ratios of less than 4. In oppose to the literature for suggestion of a constant eddy viscosity of 0.67, calibration of the Shiono and Knight model in this study showed a variable eddy viscosity for variable flow conditions. Comparison of the model and experimental results confirms correct estimation of the aforementioned parameters. <br />http://jise.scu.ac.ir/article_11805_88daad92a2b85e052f754f7879c66580.pdfshiono and knight modelshear stresssecondary floweddy viscositytrapezoidal channel |
| spellingShingle | Babak Lashkar Ara Iran Dokht Dehghani Calibration of Shiono and Knight Model to Estimate Shear Stress for Trapezoidal Channel علوم و مهندسی آبیاری shiono and knight model shear stress secondary flow eddy viscosity trapezoidal channel |
| title | Calibration of Shiono and Knight Model to Estimate Shear Stress
for Trapezoidal Channel |
| title_full | Calibration of Shiono and Knight Model to Estimate Shear Stress
for Trapezoidal Channel |
| title_fullStr | Calibration of Shiono and Knight Model to Estimate Shear Stress
for Trapezoidal Channel |
| title_full_unstemmed | Calibration of Shiono and Knight Model to Estimate Shear Stress
for Trapezoidal Channel |
| title_short | Calibration of Shiono and Knight Model to Estimate Shear Stress
for Trapezoidal Channel |
| title_sort | calibration of shiono and knight model to estimate shear stress for trapezoidal channel |
| topic | shiono and knight model shear stress secondary flow eddy viscosity trapezoidal channel |
| url | http://jise.scu.ac.ir/article_11805_88daad92a2b85e052f754f7879c66580.pdf |
| work_keys_str_mv | AT babaklashkarara calibrationofshionoandknightmodeltoestimateshearstressfortrapezoidalchannel AT irandokhtdehghani calibrationofshionoandknightmodeltoestimateshearstressfortrapezoidalchannel |