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Computational methods for complex eigenproblems in finite element analysis of structural systems with viscoelastic damping treatments. (English) Zbl 1144.74039

Summary: We present efficient numerical methods to approximate the complex eigenvalues and eigenvectors in non-proportional and non-viscous systems. These methods are specially conceived for practical engineering applications making use of the finite element analysis to determinate the effect that potential damping treatments have on natural frequencies and mode shapes of structural systems. Considering the solution of the undamped problem, the complex eigenpair is estimated by finite increments using the eigenvector derivatives. For non-proportional viscous systems with low and medium damping, a simple single-step technique is presented whose rapidity and accuracy is verified by means of numerical applications. For higher damped systems an incremental approach is proposed that keeps the accuracy without significantly increasing the computational time. For non-viscously damped systems a fast iterative modality is suggested, which allows to approximate, in an efficient and simple way, the complex eigenpair. As numerical applications, the study of a metallic beam with free layer damping treatment is completed using finite element procedures, where the damping material is modelized by an exponential model whose parameters are obtained from curve fitting to experimental data.

MSC:

74S05 Finite element methods applied to problems in solid mechanics
74H15 Numerical approximation of solutions of dynamical problems in solid mechanics
74K10 Rods (beams, columns, shafts, arches, rings, etc.)

Software:

Matlab
Full Text: DOI

References:

[1] Jones, D. I.G., Handbook of Viscoelastic Vibration Damping (2001), John Wiley & Sons: John Wiley & Sons Chichester
[2] Sun, C. T.; Lu, Y. P., Vibration Damping of Structural Elements (1995), Prentice-Hall: Prentice-Hall New Jersey · Zbl 0840.73001
[3] Nashif, A. D.; Jones, D. I.G.; Henderson, J. P., Vibration Damping (1985), John Wiley & Sons: John Wiley & Sons New York
[4] Ewins, D. J., Modal Testing (2000), Research Studies Press: Research Studies Press Baldock · Zbl 1312.70014
[5] Caughey, T. K.; O’Kelly, M. E.J., Classical normal modes in damped linear dynamic systems, J. Appl. Mech., 32, 583-588 (1965)
[6] Lanczos, C., An iteration method for the solution of the eigenvalue problem of linear differential and integral operators, J. Res. Natl. Bureau Std., 45, 4, 255-282 (1950)
[7] Arnoldi, W. E., The principle of minimized iterations in the solution of the matrix eigenvalue problem, Quart. Appl. Math., 9, 17-29 (1951) · Zbl 0042.12801
[8] Leung, A. Y.T., Subspace iterations for complex symmetric eigenproblems, J. Sound Vibr., 184, 4, 627-637 (1995) · Zbl 0982.74516
[9] Ruge, P., Eigenvalues of damped structures: vector iteration in the original space of DOF, Comput. Mech., 22, 167-173 (1998) · Zbl 0929.74129
[10] Fischer, P., Eigensolution of nonclassically damped structures by complex subspace iteration, Comput. Methods Appl. Mech. Engrg., 189, 1, 149-166 (2000) · Zbl 0986.74033
[11] Adhikari, S., Dynamics of nonviscously damped linear systems, J. Engrg. Mech., 128, 3, 328-339 (2002)
[12] Adhikari, S., Eigenrelations for nonviscously damped systems, Amer. Inst. Aeronaut. Astronaut. J., 39, 8, 1624-1630 (2001)
[13] Muller, P., Are the eigensolutions of a 1-d.o.f. system with viscoelastic damping oscillatory or not?, J. Sound Vibr., 285, 1-2, 501-509 (2005)
[14] Adhikari, S., Classical normal modes in nonviscously damped linear systems, AIAA J., 39, 5, 978-980 (2001)
[15] F. Cortés, M.J. Elejabarrieta, An approximate numerical method for the complex eigenproblem in systems characterized by a structural damping matrix, J. Sound Vibr., submitted for publication.; F. Cortés, M.J. Elejabarrieta, An approximate numerical method for the complex eigenproblem in systems characterized by a structural damping matrix, J. Sound Vibr., submitted for publication.
[16] Fox, R. L.; Kapoor, M. P., Rates of change of eigenvalues and eigenvectors, Amer. Inst. Aeronaut. Astronaut. J., 6, 12, 2426-2429 (1968) · Zbl 0181.53003
[17] Nelson, R. N., Simplified calculation of eigenvector derivatives, Amer. Inst. Aeronaut. Astronaut. J., 14, 9, 1201-1205 (1976) · Zbl 0342.65021
[18] Murthy, D. V.; Haftka, R. T., Derivatives of eigenvalues and eigenvectors of a general complex matrix, Int. J. Numer. Methods Engrg., 26, 9, 293-311 (1988) · Zbl 0637.65030
[19] Lee, I. W.; Jung, G. H., An efficient algebraic method for the computation of natural frequency and mode shape sensitivities—Part I. Distinct natural frequencies, Comput. Struct., 62, 3, 429-435 (1997) · Zbl 0912.73080
[20] Sestieri, A.; Ibrahim, S. R., Analysis of errors and approximations in the use of modal co-ordinates, J. Sound Vibr., 177, 2, 145-157 (1994) · Zbl 0945.70526
[21] Adhikari, S., Rates of change of eigenvalues and eigenvectors in damped dynamic system, Amer. Inst. Aeronaut. Astronaut. J., 37, 11, 1452-1457 (1999)
[22] Friswell, M. I.; Adhikari, S., Derivatives of complex eigenvectors using Nelson’s method, Amer. Inst. Aeronaut. Astronaut. J., 38, 12, 2355-2356 (2000)
[23] Lee, I. W.; Kim, D. O.; Jung, G. H., Natural frequency and mode shape sensitivities of damped systems: Part I. Distinct natural frequencies, J. Sound Vibr., 223, 3, 399-412 (1999)
[24] Choi, K. M.; Jo, H. K.; Kim, W. H.; Lee, I. W., Sensitivity analysis of non-conservative eigensystems, J. Sound Vibr., 274, 3-5, 997-1011 (2004)
[25] Dubigeon, S., Mécanique des Milieux Continus (1998), Tec & Doc Lavoisier: Tec & Doc Lavoisier Paris, Ch. II.1.2
[26] H.N. Özgüven, Twenty years of computational methods for harmonic response analysis of non-proportionally damped systems, in: Proceedings of the 20th International Modal Analysis Conference, Los Angeles, February 2002, vol. 1, pp. 390-396.; H.N. Özgüven, Twenty years of computational methods for harmonic response analysis of non-proportionally damped systems, in: Proceedings of the 20th International Modal Analysis Conference, Los Angeles, February 2002, vol. 1, pp. 390-396.
[27] Adhikari, S., Derivative of eigensolutions of nonviscously damped linear systems, Amer. Inst. Aeronaut. Astronaut. J., 40, 10, 2061-2069 (2002)
[28] F. Cortés, M.J. Elejabarrieta, Viscoelastic materials characterisation using the seismic response, Mater. Des., submitted for publication.; F. Cortés, M.J. Elejabarrieta, Viscoelastic materials characterisation using the seismic response, Mater. Des., submitted for publication.
[29] Soundown Corporation. Available from: http://www.soundown.com; Soundown Corporation. Available from: http://www.soundown.com
[30] Biot, M. A., Variational principles in irreversible thermodynamics with application to viscoelasticity, Phys. Rev., 97, 1463-1469 (1995) · Zbl 0065.42003
[31] Hughes, T. J.R., The Finite Element Method: Linear Static and Dynamic Finite Element Analysis (2000), Dover Publishers: Dover Publishers New York · Zbl 1191.74002
[32] Bathe, K. J., Finite Element Procedures (1996), Prentice-Hall: Prentice-Hall New Jersey · Zbl 0511.73065
[33] Using MATLAB Version 6, The MathWorks Inc., Natick, USA, 2001.; Using MATLAB Version 6, The MathWorks Inc., Natick, USA, 2001.
[34] Nelder, J. A.; Mead, R., A simplex method for function minimization, Comput. J., 7, 308-313 (1965) · Zbl 0229.65053
[35] Moler, C. B.; Stewart, G. W., An algorithm for generalized matrix eigenvalues problems, SIAM J. Numer. Anal., 10, 2, 241-259 (1973) · Zbl 0253.65019
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