Finite element structural model updating by using experimental frequency response functions

Download

index.pdf

Date

2009

Author

Öztürk, Murat

Metadata

Show full item record

Item Usage Stats

239
views

143
downloads

Initial forms of analytical models created to simulate real engineering structures may generally yield dynamic response predictions different than those obtained from experimental tests. Since testing a real structure under every possible excitation is not practical, it is essential to transform the initial mathematical model to a model which reflects the characteristics of the actual structure in a better way. By using structural model updating techniques, the initial mathematical model is adjusted so that it simulates the experimental measurements more closely. In this study, a sensitivity-based finite element (FE) model updating method using experimental frequency response (FRF) data is presented. This study bases on a technique developed in an earlier study on the computation of the so-called Mis-correlation Index (MCI) used for identifying the system matrices which require updating. MCI values are calculated for each required coordinate, and non-zero numerical values indicate coordinates carrying error. In this work a new model updating procedure based on the minimization of this index is developed. The method uses sensitivity approach. FE models are iteratively updated by minimizing MCI values using sensitivities. The validation of the method is realized through some case studies. In order to demonstrate the application of the method for real systems, a real test data obtained from the modal test of a scaled aircraft model (GARTEUR SM-AG19) is used. In the application, the FE model of the scaled aircraft is updated. In the case studies the generic software developed in this study is used along with some commercial programs.

Subject Keywords

Mechanical engineering.

URI

http://etd.lib.metu.edu.tr/upload/2/12610608/index.pdf
https://hdl.handle.net/11511/18640

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Mechanical properties identification of viscoelastic / hyperelastic materials based on experimental data Tabakcı, Alican; Konukseven, Erhan İlhan; Erkmen, Aydan Müşerref; Department of Mechanical Engineering (2010) Mechanical simulation of viscoelastic materials and assigning a viscoelastic material to the modeled parts in the simulations are difficult task. For the simulations, material model should be well chosen and material coefficients of the chosen models should be known. In order to obtain accurate simulations, hyperelastic characteristics of the viscoelastic materials should be investigated and hyperelastic model should be incorporated in the solutions. Material models and material model’s coefficients are cho...
Fully Coupled Smoothed Particle Hydrodynamics-Finite Element Method Approach for Fluid-Structure Interaction Problems With Large Deflections Dincer, A. Ersin; Demir, Abdullah; Bozkuş, Zafer; Tijsseling, Arris S. (ASME International, 2019-08-01) In this study, a combination of the smoothed particle hydrodynamics (SPH) and finite element method (FEM) solving the complex problem of interaction between fluid with free surface and an elastic structure is studied. A brief description of SPH and FEM is presented. Contact mechanics is used for the coupling between fluid and structure, which are simulated with SPH and FEM, respectively. In the proposed method, to couple meshfree and mesh-based methods, fluid and structure are solved together by a complete ...
A genetic algorithm for 2d shape optimization Chen, Wei Hang; Oral, Süha; Department of Mechanical Engineering (2008) In this study, an optimization code has been developed based on genetic algorithms associated with the finite element modeling for the shape optimization of plane stress problems. In genetic algorithms, constraints are mostly handled by using the concept of penalty functions, which penalize infeasible solutions by reducing their fitness values in proportion to the degrees of constraint violation. In this study, An Improved GA Penalty Scheme is used. The proposed method gives information about unfeasible ind...
Analysis of thin walled open section tapered beams using hybrid stress finite element method Akman, Mehmet Nazım; Oral, Süha; Department of Mechanical Engineering (2008) In this thesis, hybrid stress finite element is formulated for the analysis of the isotropic, thin walled, open section beams with variable cross sections. The beam element has two nodes each having seven degrees of freedom. Assumption of stress field is sufficient to determine the element stiffness matrix. Axial, flexural and torsional effects are taken into account in the analysis. The methodology can be applied both to the tapered and the uniform beams. Throughout this study, firstly element cross-sectio...
Large deformation analysis of shells under impulsive loading Evcim, Mehmet; Darendeliler, Haluk; Department of Mechanical Engineering (2010) In this thesis large deformation behavior of shell structures under high intensity transient loading conditions is investigated by means of finite element method. For this purpose an explicit finite element program is developed with interactive user interface. The developed program deals with geometric and material nonlinearities which stem from large deformation elastic - plastic behavior. Results of the developed code are compared with the experimental data taken from the literature and simulation results...

Citation Formats

M. Öztürk, “Finite element structural model updating by using experimental frequency response functions,” M.S. - Master of Science, Middle East Technical University, 2009.