Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways
Fluctuating bottom-pressures on stepped chutes are relevant for the spillway design. An abrupt slope reduction causes a local alteration of the bottom-pressure development. Little information is available regarding the air–water flow properties near an abrupt slope reduction on stepped chutes, parti...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-12-01
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| Series: | Water |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4441/14/1/41 |
| _version_ | 1797497101857325056 |
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| author | Mohammad J. Ostad Mirza Tehrani Jorge Matos Michael Pfister Anton J. Schleiss |
| author_facet | Mohammad J. Ostad Mirza Tehrani Jorge Matos Michael Pfister Anton J. Schleiss |
| author_sort | Mohammad J. Ostad Mirza Tehrani |
| collection | DOAJ |
| description | Fluctuating bottom-pressures on stepped chutes are relevant for the spillway design. An abrupt slope reduction causes a local alteration of the bottom-pressure development. Little information is available regarding the air–water flow properties near an abrupt slope reduction on stepped chutes, particularly on the local pressure evolution. Nevertheless, the option of providing a chute slope reduction may be of interest in spillway layout. The experiments presented herein include pressure distributions on both vertical and horizontal step faces, subsequent to an abrupt slope reduction on stepped chutes. A relatively large-scale physical model including abrupt slope reductions from 50° to 18.6° and from 50° to 30° was used, operated with skimming flow. The data indicate a substantial influence of the tested slope reductions on the bottom-pressure development. In the vicinity of the slope reduction, the mean pressure head near the edge of the horizontal step face reached 0.4 to 0.6 times the velocity head upstream of the slope reduction, for critical flow depths normalized by the step height ranging between 2.6 and 4.6. |
| first_indexed | 2024-03-10T03:12:42Z |
| format | Article |
| id | doaj.art-bfaeda1cd915492a8148f12600d307c1 |
| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-10T03:12:42Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-bfaeda1cd915492a8148f12600d307c12023-11-23T12:31:56ZengMDPI AGWater2073-44412021-12-011414110.3390/w14010041Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped SpillwaysMohammad J. Ostad Mirza Tehrani0Jorge Matos1Michael Pfister2Anton J. Schleiss3Laboratory of Hydraulic Constructions (LCH), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, SwitzerlandCERIS, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, PortugalCivil Engineering Department, Haute Ecole d’Ingénierie et d’Architecture de Fribourg (HEIA-FR, HES-SO), CH-1705 Fribourg, SwitzerlandLaboratory of Hydraulic Constructions (LCH), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, SwitzerlandFluctuating bottom-pressures on stepped chutes are relevant for the spillway design. An abrupt slope reduction causes a local alteration of the bottom-pressure development. Little information is available regarding the air–water flow properties near an abrupt slope reduction on stepped chutes, particularly on the local pressure evolution. Nevertheless, the option of providing a chute slope reduction may be of interest in spillway layout. The experiments presented herein include pressure distributions on both vertical and horizontal step faces, subsequent to an abrupt slope reduction on stepped chutes. A relatively large-scale physical model including abrupt slope reductions from 50° to 18.6° and from 50° to 30° was used, operated with skimming flow. The data indicate a substantial influence of the tested slope reductions on the bottom-pressure development. In the vicinity of the slope reduction, the mean pressure head near the edge of the horizontal step face reached 0.4 to 0.6 times the velocity head upstream of the slope reduction, for critical flow depths normalized by the step height ranging between 2.6 and 4.6.https://www.mdpi.com/2073-4441/14/1/41air–water flowbottom-pressureskimming flowslope reductionstepped spillway |
| spellingShingle | Mohammad J. Ostad Mirza Tehrani Jorge Matos Michael Pfister Anton J. Schleiss Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways Water air–water flow bottom-pressure skimming flow slope reduction stepped spillway |
| title | Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways |
| title_full | Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways |
| title_fullStr | Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways |
| title_full_unstemmed | Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways |
| title_short | Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways |
| title_sort | bottom pressure development due to an abrupt slope reduction at stepped spillways |
| topic | air–water flow bottom-pressure skimming flow slope reduction stepped spillway |
| url | https://www.mdpi.com/2073-4441/14/1/41 |
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