Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load
This paper presents a numerical analysis of the influence of the von Karman vortex shedding at the blade trailing edge on the hydrodynamics of a recently installed small hydro Francis turbine manifesting very loud and high-frequency acoustic pulsations when operating close to the nominal load. A red...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-08-01
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| Series: | International Journal of Turbomachinery, Propulsion and Power |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2504-186X/8/3/27 |
| _version_ | 1797579564687294464 |
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| author | Giacomo Zanetti Giovanna Cavazzini Alberto Santolin |
| author_facet | Giacomo Zanetti Giovanna Cavazzini Alberto Santolin |
| author_sort | Giacomo Zanetti |
| collection | DOAJ |
| description | This paper presents a numerical analysis of the influence of the von Karman vortex shedding at the blade trailing edge on the hydrodynamics of a recently installed small hydro Francis turbine manifesting very loud and high-frequency acoustic pulsations when operating close to the nominal load. A reduced single-passage numerical model is developed to reduce the computational effort of the simulation while ensuring high accuracy in the assessment of fluid flow. The accuracy of the proposed numerical approach is investigated by comparing the frequency spectrum of the experimentally acquired acoustic frequency and the numerical pressure signals, confirming the nature of the machine’s vibrations. The validated numerical model represents a useful tool for an in-depth analysis of the machine’s hydrodynamics in the preliminary design phases. The proposed approach represents a valid alternative to the traditional correlation-based approach for the evaluation of the von Karman shedding frequency with less computational effort compared with a transient simulation of the entire machine. |
| first_indexed | 2024-03-10T22:37:57Z |
| format | Article |
| id | doaj.art-2dc77112cb744bf3a36f597128110a06 |
| institution | Directory Open Access Journal |
| issn | 2504-186X |
| language | English |
| last_indexed | 2024-03-10T22:37:57Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Turbomachinery, Propulsion and Power |
| spelling | doaj.art-2dc77112cb744bf3a36f597128110a062023-11-19T11:13:05ZengMDPI AGInternational Journal of Turbomachinery, Propulsion and Power2504-186X2023-08-01832710.3390/ijtpp8030027Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal LoadGiacomo Zanetti0Giovanna Cavazzini1Alberto Santolin2Department of Industrial Engineering, University of Padova, Via Venezia 1, 35131 Padova, ItalyDepartment of Industrial Engineering, University of Padova, Via Venezia 1, 35131 Padova, Italy45 Engineering S.r.l., Corte delle Filande 16, 36075 Montecchio Maggiore, ItalyThis paper presents a numerical analysis of the influence of the von Karman vortex shedding at the blade trailing edge on the hydrodynamics of a recently installed small hydro Francis turbine manifesting very loud and high-frequency acoustic pulsations when operating close to the nominal load. A reduced single-passage numerical model is developed to reduce the computational effort of the simulation while ensuring high accuracy in the assessment of fluid flow. The accuracy of the proposed numerical approach is investigated by comparing the frequency spectrum of the experimentally acquired acoustic frequency and the numerical pressure signals, confirming the nature of the machine’s vibrations. The validated numerical model represents a useful tool for an in-depth analysis of the machine’s hydrodynamics in the preliminary design phases. The proposed approach represents a valid alternative to the traditional correlation-based approach for the evaluation of the von Karman shedding frequency with less computational effort compared with a transient simulation of the entire machine.https://www.mdpi.com/2504-186X/8/3/27Francis turbinesinterblade vorticesvon Karman vorticesmechanical resonance |
| spellingShingle | Giacomo Zanetti Giovanna Cavazzini Alberto Santolin Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load International Journal of Turbomachinery, Propulsion and Power Francis turbines interblade vortices von Karman vortices mechanical resonance |
| title | Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load |
| title_full | Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load |
| title_fullStr | Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load |
| title_full_unstemmed | Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load |
| title_short | Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load |
| title_sort | effect of the von karman shedding frequency on the hydrodynamics of a francis turbine operating at nominal load |
| topic | Francis turbines interblade vortices von Karman vortices mechanical resonance |
| url | https://www.mdpi.com/2504-186X/8/3/27 |
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