Theoretical Stable Hydraulic Section based on the Principle of Least Action
Abstract Despite decades of effort, stable hydraulic geometry for an open channel water flow has hardly been established because of too many unknown variables for too few rational relationships. This article derives the most efficient channel cross section using calculus of variations for the given...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2019-05-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-019-44347-4 |
| _version_ | 1818997762379743232 |
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| author | Noriaki Ohara Katsu Yamatani |
| author_facet | Noriaki Ohara Katsu Yamatani |
| author_sort | Noriaki Ohara |
| collection | DOAJ |
| description | Abstract Despite decades of effort, stable hydraulic geometry for an open channel water flow has hardly been established because of too many unknown variables for too few rational relationships. This article derives the most efficient channel cross section using calculus of variations for the given flow area at the minimum wetting perimeter length, which is equivalent to the principle of least action. Analysis indicates that water can most efficiently flow in a semi-ellipse section channel with minimum friction and erosion. Anisotropy in channel erodibility was found to be necessary in the natural stable channel characterization because gravitation force and channel bank consolidation cannot be ignored in earth surface material. This channel cross section, based on the principle of least action, may be regarded as the theoretical stable hydraulic section for erodible bed, which was comparable to the observed river cross-sections during high flow periods. |
| first_indexed | 2024-12-20T21:50:47Z |
| format | Article |
| id | doaj.art-2f7901234bd74899a657e9914bf129ba |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-20T21:50:47Z |
| publishDate | 2019-05-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-2f7901234bd74899a657e9914bf129ba2022-12-21T19:25:33ZengNature PortfolioScientific Reports2045-23222019-05-01911610.1038/s41598-019-44347-4Theoretical Stable Hydraulic Section based on the Principle of Least ActionNoriaki Ohara0Katsu Yamatani1Department of Civil and Architectural Engineering, University of WyomingDepartment of Urban Science, Meijo UniversityAbstract Despite decades of effort, stable hydraulic geometry for an open channel water flow has hardly been established because of too many unknown variables for too few rational relationships. This article derives the most efficient channel cross section using calculus of variations for the given flow area at the minimum wetting perimeter length, which is equivalent to the principle of least action. Analysis indicates that water can most efficiently flow in a semi-ellipse section channel with minimum friction and erosion. Anisotropy in channel erodibility was found to be necessary in the natural stable channel characterization because gravitation force and channel bank consolidation cannot be ignored in earth surface material. This channel cross section, based on the principle of least action, may be regarded as the theoretical stable hydraulic section for erodible bed, which was comparable to the observed river cross-sections during high flow periods.https://doi.org/10.1038/s41598-019-44347-4 |
| spellingShingle | Noriaki Ohara Katsu Yamatani Theoretical Stable Hydraulic Section based on the Principle of Least Action Scientific Reports |
| title | Theoretical Stable Hydraulic Section based on the Principle of Least Action |
| title_full | Theoretical Stable Hydraulic Section based on the Principle of Least Action |
| title_fullStr | Theoretical Stable Hydraulic Section based on the Principle of Least Action |
| title_full_unstemmed | Theoretical Stable Hydraulic Section based on the Principle of Least Action |
| title_short | Theoretical Stable Hydraulic Section based on the Principle of Least Action |
| title_sort | theoretical stable hydraulic section based on the principle of least action |
| url | https://doi.org/10.1038/s41598-019-44347-4 |
| work_keys_str_mv | AT noriakiohara theoreticalstablehydraulicsectionbasedontheprincipleofleastaction AT katsuyamatani theoreticalstablehydraulicsectionbasedontheprincipleofleastaction |