Modares Mechanical Engineering

Modares Mechanical Engineering

Updating of gas turbine finite element model by experimental modal analysis results and modeling disc/blade joint

Authors
kaveh abbasi 1
Ali Siami 2
Babak Khodabandeloo 3
masood asayesh 4
1 Department of mechanical engineering, Islamic Azad university, Eslam Abad-E-gharb, Eslam Abad-E-gharb, Kemanshah, Iran
2 Department of Rotating Equipment, Power Generation Research Center, Niroo Research Institute, Tehran, Iran
3 Department of Geoscience and Petroleum, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
4 Faculty-niroo research institute(nri)
Abstract
The precise finite element model is an efficient tool for vibrational analysis. It should be mentioned that, in structural dynamic analysis finite element models of system should be able to accurately predict system characteristics such as natural frequencies. Contrary to static analysis, in structural dynamic analysis, it is not possible to overestimate system characteristics or apply safety factor for predicted characteristics; that means that the exact values of system characteristics such as natural frequencies, should be derived in structural dynamic. According to this, constructing a reliable model in the structure dynamic always has great degree of importance in vibrational analysis. In this study, it has been tried to extract a reliable finite element model for a row of a sample turbine of RollsRoyce brand using empirical results. So, the material properties of the disk and the connection between the disk and the blade are corrected and updated using experimental modal analysis results. Also, it has been tried to propose new method to model and update the disk and blade joint. Finally, reliable finite element model could be used for more analysis such as derivation of Campbell diagrams of system.
Keywords
Finite Element Modeling
Model Updating
Gas Turbine
Modal Analysis
Disc and blade joint

Subjects

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Modares Mechanical Engineering
Volume 18, Issue 8
December 2018
Pages 202-208