FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS
The presence of crack in a structure tends to modify its modal parameters (natural frequencies and mode shapes). The fact can be used inversely to predict the crack parameters (crack depth and its location) from measurement of the changes in the modal parameters, once a functional relationship betwe...
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| Format: | Article |
| Language: | English |
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Taylor's University
2016-12-01
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| Series: | Journal of Engineering Science and Technology |
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| Online Access: | http://jestec.taylors.edu.my/Vol%2011%20issue%2012%20December%202016/11_12_9.pdf |
| _version_ | 1818502120336261120 |
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| author | RAVI PRAKASH BABU KOCHARLA RAGHU KUMAR BANDLAM MALLIKARJUNA RAO KUCHIBOTLA |
| author_facet | RAVI PRAKASH BABU KOCHARLA RAGHU KUMAR BANDLAM MALLIKARJUNA RAO KUCHIBOTLA |
| author_sort | RAVI PRAKASH BABU KOCHARLA |
| collection | DOAJ |
| description | The presence of crack in a structure tends to modify its modal parameters (natural frequencies and mode shapes). The fact can be used inversely to predict the crack parameters (crack depth and its location) from measurement of the changes in the modal parameters, once a functional relationship between them has been
established. The machine components like turbine blade can be treated as a cantilever beam. Vibration analysis of cantilever beam can be extended successfully to develop online crack detection methodology in turbine blade. In the present work, finite element model of a cantilever beam for flexural vibrations has been considered by including two transverse open U-notches. The modal analysis has been carried out on cantilever beam with two U-notches and observed the influence of one U-notch on the other for natural frequencies and mode shapes. It is found that a certain frequency may correspond to different crack depths and locations. Later, by using a central difference approximation, curvature
mode shapes were then calculated from the displacement mode shapes. The location and depth corresponding to any peak on this curve becomes a possible notch location and depth. The identification procedure presented in this study is a useful tool for detection of multiple cracks in a turbine blade. |
| first_indexed | 2024-12-10T21:05:32Z |
| format | Article |
| id | doaj.art-a27cfe2d96f54b81bef368a330452dd6 |
| institution | Directory Open Access Journal |
| issn | 1823-4690 |
| language | English |
| last_indexed | 2024-12-10T21:05:32Z |
| publishDate | 2016-12-01 |
| publisher | Taylor's University |
| record_format | Article |
| series | Journal of Engineering Science and Technology |
| spelling | doaj.art-a27cfe2d96f54b81bef368a330452dd62022-12-22T01:33:39ZengTaylor's UniversityJournal of Engineering Science and Technology1823-46902016-12-01111217581770FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERSRAVI PRAKASH BABU KOCHARLA0 RAGHU KUMAR BANDLAM1MALLIKARJUNA RAO KUCHIBOTLA21Department of Mechanical Engineering, KLEF University, Guntur, Andhra Pradesh, India. 3Department of Mechanical Engineering, JNTUK, Kakinada, Andhra Pradesh, India.2Department of Mechanical Engineering, PVP Siddhartha Institute of Technology, Vijayawada, Andhra Pradesh, IndiaDepartment of Mechanical Engineering, JNTUK, Kakinada, Andhra Pradesh, IndiaThe presence of crack in a structure tends to modify its modal parameters (natural frequencies and mode shapes). The fact can be used inversely to predict the crack parameters (crack depth and its location) from measurement of the changes in the modal parameters, once a functional relationship between them has been established. The machine components like turbine blade can be treated as a cantilever beam. Vibration analysis of cantilever beam can be extended successfully to develop online crack detection methodology in turbine blade. In the present work, finite element model of a cantilever beam for flexural vibrations has been considered by including two transverse open U-notches. The modal analysis has been carried out on cantilever beam with two U-notches and observed the influence of one U-notch on the other for natural frequencies and mode shapes. It is found that a certain frequency may correspond to different crack depths and locations. Later, by using a central difference approximation, curvature mode shapes were then calculated from the displacement mode shapes. The location and depth corresponding to any peak on this curve becomes a possible notch location and depth. The identification procedure presented in this study is a useful tool for detection of multiple cracks in a turbine blade.http://jestec.taylors.edu.my/Vol%2011%20issue%2012%20December%202016/11_12_9.pdfonce a functional relationship between them has been established. The machine components like turbine blade can be treated as a cantilever beam. Vibration analysis of cantilever beam can be extended successfully to develop online crack detection methodology in turbine blade. In the present workfinite element model of a cantilever beam for flexural vibrations has been considered by including two transverse open U-notches. The modal analysis has been carried out on cantilever beam with two U-notches and observed the influence of one U-notch on the other for natural frequencies and mode shapes. It is found that a certain frequency may correspond to different crack depths and locations. Laterby using a central difference approximationFinite elementNatural frequencyMode shapesCantileverMultiple cracks |
| spellingShingle | RAVI PRAKASH BABU KOCHARLA RAGHU KUMAR BANDLAM MALLIKARJUNA RAO KUCHIBOTLA FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS Journal of Engineering Science and Technology once a functional relationship between them has been established. The machine components like turbine blade can be treated as a cantilever beam. Vibration analysis of cantilever beam can be extended successfully to develop online crack detection methodology in turbine blade. In the present work finite element model of a cantilever beam for flexural vibrations has been considered by including two transverse open U-notches. The modal analysis has been carried out on cantilever beam with two U-notches and observed the influence of one U-notch on the other for natural frequencies and mode shapes. It is found that a certain frequency may correspond to different crack depths and locations. Later by using a central difference approximation Finite element Natural frequency Mode shapes Cantilever Multiple cracks |
| title | FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS |
| title_full | FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS |
| title_fullStr | FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS |
| title_full_unstemmed | FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS |
| title_short | FINITE ELEMENT MODELLING OF A TURBINE BLADE TO STUDY THE EFFECT OF MULTIPLE CRACKS USING MODAL PARAMETERS |
| title_sort | finite element modelling of a turbine blade to study the effect of multiple cracks using modal parameters |
| topic | once a functional relationship between them has been established. The machine components like turbine blade can be treated as a cantilever beam. Vibration analysis of cantilever beam can be extended successfully to develop online crack detection methodology in turbine blade. In the present work finite element model of a cantilever beam for flexural vibrations has been considered by including two transverse open U-notches. The modal analysis has been carried out on cantilever beam with two U-notches and observed the influence of one U-notch on the other for natural frequencies and mode shapes. It is found that a certain frequency may correspond to different crack depths and locations. Later by using a central difference approximation Finite element Natural frequency Mode shapes Cantilever Multiple cracks |
| url | http://jestec.taylors.edu.my/Vol%2011%20issue%2012%20December%202016/11_12_9.pdf |
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