Effect of Guide Vane Clearance Gap on Francis Turbine Performance
Francis turbine guide vanes have pivoted support with external control mechanism, for conversion of pressure to kinetic energy and to direct them to runner vanes. This movement along the support is dependent on variation of load and flow (operating conditions). Small clearance gaps between facing pl...
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| Format: | Article |
| Language: | English |
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MDPI AG
2016-04-01
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| Series: | Energies |
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| Online Access: | http://www.mdpi.com/1996-1073/9/4/275 |
| _version_ | 1798025433439010816 |
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| author | Ravi Koirala Baoshan Zhu Hari Prasad Neopane |
| author_facet | Ravi Koirala Baoshan Zhu Hari Prasad Neopane |
| author_sort | Ravi Koirala |
| collection | DOAJ |
| description | Francis turbine guide vanes have pivoted support with external control mechanism, for conversion of pressure to kinetic energy and to direct them to runner vanes. This movement along the support is dependent on variation of load and flow (operating conditions). Small clearance gaps between facing plates and the upper and lower guide vane tips are available to aid this movement, through which leakage flow occurs. This secondary flow disturbs the main flow stream, resulting performance loss. Additionally, these increased horseshoe vortex, in presence of sand, when crosses through the gaps, both the surfaces are eroded. This causes further serious effect on performance and structural property by increasing gaps. This paper discusses the observation of the severity in hydropower plants and effect of clearance gaps on general performance of the Francis turbine through computational methods. It also relates the primary result with the empirical relation for leakage flow prediction. Additionally, a possible method to computationally estimate thickness depletion has also been presented. With increasing clearance gap, leakage increases, which lowers energy conversion and turbine efficiency along with larger secondary vortex. |
| first_indexed | 2024-04-11T18:18:59Z |
| format | Article |
| id | doaj.art-837155aedc6d49a38650516fa289a8ce |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-11T18:18:59Z |
| publishDate | 2016-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-837155aedc6d49a38650516fa289a8ce2022-12-22T04:09:49ZengMDPI AGEnergies1996-10732016-04-019427510.3390/en9040275en9040275Effect of Guide Vane Clearance Gap on Francis Turbine PerformanceRavi Koirala0Baoshan Zhu1Hari Prasad Neopane2State Key Laboratory of Hydroscience and Engineering, Department of Thermal Engineering, Tsinghua University, Beijing 100084, ChinaState Key Laboratory of Hydroscience and Engineering, Department of Thermal Engineering, Tsinghua University, Beijing 100084, ChinaTurbine Testing Lab, Kathmandu University, P.O. Box 6250, Dhulikhel, NepalFrancis turbine guide vanes have pivoted support with external control mechanism, for conversion of pressure to kinetic energy and to direct them to runner vanes. This movement along the support is dependent on variation of load and flow (operating conditions). Small clearance gaps between facing plates and the upper and lower guide vane tips are available to aid this movement, through which leakage flow occurs. This secondary flow disturbs the main flow stream, resulting performance loss. Additionally, these increased horseshoe vortex, in presence of sand, when crosses through the gaps, both the surfaces are eroded. This causes further serious effect on performance and structural property by increasing gaps. This paper discusses the observation of the severity in hydropower plants and effect of clearance gaps on general performance of the Francis turbine through computational methods. It also relates the primary result with the empirical relation for leakage flow prediction. Additionally, a possible method to computationally estimate thickness depletion has also been presented. With increasing clearance gap, leakage increases, which lowers energy conversion and turbine efficiency along with larger secondary vortex.http://www.mdpi.com/1996-1073/9/4/275guide vanessediment erosionclearance gapperformanceleakage flow |
| spellingShingle | Ravi Koirala Baoshan Zhu Hari Prasad Neopane Effect of Guide Vane Clearance Gap on Francis Turbine Performance Energies guide vanes sediment erosion clearance gap performance leakage flow |
| title | Effect of Guide Vane Clearance Gap on Francis Turbine Performance |
| title_full | Effect of Guide Vane Clearance Gap on Francis Turbine Performance |
| title_fullStr | Effect of Guide Vane Clearance Gap on Francis Turbine Performance |
| title_full_unstemmed | Effect of Guide Vane Clearance Gap on Francis Turbine Performance |
| title_short | Effect of Guide Vane Clearance Gap on Francis Turbine Performance |
| title_sort | effect of guide vane clearance gap on francis turbine performance |
| topic | guide vanes sediment erosion clearance gap performance leakage flow |
| url | http://www.mdpi.com/1996-1073/9/4/275 |
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