Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack
Crack appearance in the blade is the most common type of fatigue damage in Francis turbines. However, it is sometimes difficult to detect cracks in time using the current monitoring system, even when they are very large. To better monitor cracks, it is imperative to research the effect of a crack on...
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-06-01
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| Series: | Energies |
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| Online Access: | http://www.mdpi.com/1996-1073/11/7/1630 |
| _version_ | 1811262730082975744 |
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| author | Ming Zhang David Valentin Carme Valero Mònica Egusquiza Weiqiang Zhao |
| author_facet | Ming Zhang David Valentin Carme Valero Mònica Egusquiza Weiqiang Zhao |
| author_sort | Ming Zhang |
| collection | DOAJ |
| description | Crack appearance in the blade is the most common type of fatigue damage in Francis turbines. However, it is sometimes difficult to detect cracks in time using the current monitoring system, even when they are very large. To better monitor cracks, it is imperative to research the effect of a crack on the dynamic behavior of a Francis turbine. In this paper, the dynamic behavior of a Francis turbine runner model with a crack has been researched numerically. The intact numerical model was first validated by the experimental data available. Then, a crack was created at the intersection line between one blade and the crown. The change in dynamic behavior with increasing crack length has been investigated. Crack-induced vibration localization theory has been used to explain the dynamic behavior changes due to the crack. Modal analysis showed that the adopted theory could basically explain the modal behavior change due to the crack. The FFT results of the modal shapes and the localization factors (LF) has been used to explain the forced response changes due to the crack. Based on the above analysis, the challenge of crack monitoring has been analyzed. This research provides some references for more advanced monitoring technologies. |
| first_indexed | 2024-04-12T19:30:40Z |
| format | Article |
| id | doaj.art-86e45dd66651466d90700f9bb1430c5c |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-12T19:30:40Z |
| publishDate | 2018-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-86e45dd66651466d90700f9bb1430c5c2022-12-22T03:19:20ZengMDPI AGEnergies1996-10732018-06-01117163010.3390/en11071630en11071630Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a CrackMing Zhang0David Valentin1Carme Valero2Mònica Egusquiza3Weiqiang Zhao4Center for Industrial Diagnostics and Fluid Dynamics (CDIF), Polytechnic University of Catalonia (UPC), Av. Diagonal, 647, ETSEIB, CO 08028 Barcelona, SpainCenter for Industrial Diagnostics and Fluid Dynamics (CDIF), Polytechnic University of Catalonia (UPC), Av. Diagonal, 647, ETSEIB, CO 08028 Barcelona, SpainCenter for Industrial Diagnostics and Fluid Dynamics (CDIF), Polytechnic University of Catalonia (UPC), Av. Diagonal, 647, ETSEIB, CO 08028 Barcelona, SpainCenter for Industrial Diagnostics and Fluid Dynamics (CDIF), Polytechnic University of Catalonia (UPC), Av. Diagonal, 647, ETSEIB, CO 08028 Barcelona, SpainCenter for Industrial Diagnostics and Fluid Dynamics (CDIF), Polytechnic University of Catalonia (UPC), Av. Diagonal, 647, ETSEIB, CO 08028 Barcelona, SpainCrack appearance in the blade is the most common type of fatigue damage in Francis turbines. However, it is sometimes difficult to detect cracks in time using the current monitoring system, even when they are very large. To better monitor cracks, it is imperative to research the effect of a crack on the dynamic behavior of a Francis turbine. In this paper, the dynamic behavior of a Francis turbine runner model with a crack has been researched numerically. The intact numerical model was first validated by the experimental data available. Then, a crack was created at the intersection line between one blade and the crown. The change in dynamic behavior with increasing crack length has been investigated. Crack-induced vibration localization theory has been used to explain the dynamic behavior changes due to the crack. Modal analysis showed that the adopted theory could basically explain the modal behavior change due to the crack. The FFT results of the modal shapes and the localization factors (LF) has been used to explain the forced response changes due to the crack. Based on the above analysis, the challenge of crack monitoring has been analyzed. This research provides some references for more advanced monitoring technologies.http://www.mdpi.com/1996-1073/11/7/1630Francis turbinecrackdynamic behaviorvibration localizationlumped parameter modelocalization factorforced response |
| spellingShingle | Ming Zhang David Valentin Carme Valero Mònica Egusquiza Weiqiang Zhao Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack Energies Francis turbine crack dynamic behavior vibration localization lumped parameter mode localization factor forced response |
| title | Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack |
| title_full | Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack |
| title_fullStr | Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack |
| title_full_unstemmed | Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack |
| title_short | Numerical Study on the Dynamic Behavior of a Francis Turbine Runner Model with a Crack |
| title_sort | numerical study on the dynamic behavior of a francis turbine runner model with a crack |
| topic | Francis turbine crack dynamic behavior vibration localization lumped parameter mode localization factor forced response |
| url | http://www.mdpi.com/1996-1073/11/7/1630 |
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