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Buckling, vibration, and flutter behavior of laminated composite panels with flaws subjected to nonuniform follower forces / Sauvik Biswas in Journal of engineering mechanics, Vol. 138 N° 4 (Avril 2012) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 138 N° 4 (Avril 2012) . - pp.347- 357 Titre : Buckling, vibration, and flutter behavior of laminated composite panels with flaws subjected to nonuniform follower forces Type de document : texte imprimé Auteurs : Sauvik Biswas, Auteur ; P. K. Datta, Auteur ; C.D. Kong, Auteur Année de publication : 2012 Article en page(s) : pp.347- 357 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Anisotropic  damage  Follower  force  Nonuniform  loading  Composite  Instability Résumé : The present work uses a finite-element approach to study vibration, buckling, and dynamic instability characteristics in damaged cross-ply and angle-ply curved panels. The panels are subjected to nonuniform, centrally, and edge-distributed follower loading. First order shear-deformation theory was used to model the doubly curved panels and was formulated in accordance with Sanders’ first approximation. An anisotropic damage formulation was used to model damage. An analysis was carried out on plate and shallow shells to obtain vibration, buckling, and static instability (i.e., divergence) and dynamic instability (i.e., flutter) behavior. The effects of load type, load width, damage, and damage location on natural frequency, buckling load, divergence load, flutter load and flutter frequency were studied. The effect of curvature to improve the stability characteristics of panels is discussed. The desirable position of damage on a panel is discussed on the basis of different stability behavior. Results indicate that narrow edge loading is undesirable in most cases. ISSN : 0733-3999 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29EM.1943-7889.0000333 [article] Buckling, vibration, and flutter behavior of laminated composite panels with flaws subjected to nonuniform follower forces [texte imprimé] / Sauvik Biswas, Auteur ; P. K. Datta, Auteur ; C.D. Kong, Auteur . - 2012 . - pp.347- 357. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 138 N° 4 (Avril 2012) . - pp.347- 357 Mots-clés : Anisotropic  damage  Follower  force  Nonuniform  loading  Composite  Instability Résumé : The present work uses a finite-element approach to study vibration, buckling, and dynamic instability characteristics in damaged cross-ply and angle-ply curved panels. The panels are subjected to nonuniform, centrally, and edge-distributed follower loading. First order shear-deformation theory was used to model the doubly curved panels and was formulated in accordance with Sanders’ first approximation. An anisotropic damage formulation was used to model damage. An analysis was carried out on plate and shallow shells to obtain vibration, buckling, and static instability (i.e., divergence) and dynamic instability (i.e., flutter) behavior. The effects of load type, load width, damage, and damage location on natural frequency, buckling load, divergence load, flutter load and flutter frequency were studied. The effect of curvature to improve the stability characteristics of panels is discussed. The desirable position of damage on a panel is discussed on the basis of different stability behavior. Results indicate that narrow edge loading is undesirable in most cases. ISSN : 0733-3999 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29EM.1943-7889.0000333

Combination resonance instability of curved panels with cutout subjected to nonuniform loading with damping / Ratnakar. S. Udar in Journal of engineering mechanics, Vol. 134 N° 7 (Juillet 2008) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 134 N° 7 (Juillet 2008) . - pp.555-566 Titre : Combination resonance instability of curved panels with cutout subjected to nonuniform loading with damping Type de document : texte imprimé Auteurs : Ratnakar. S. Udar, Auteur ; P. K. Datta, Auteur Année de publication : 2010 Article en page(s) : pp.555-566 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Damping  Resonance  Vibration  Panels. Résumé : The dynamic instability of doubly curved panels with a centrally located circular cutout, subjected to nonuniform compressive in-plane harmonic edge loading is investigated. The present work deals with the problem of the occurrence of combination resonances in contrast to single (mode) resonances in parametrically excited doubly curved panels with a central circular cutout. The method of multiple scales is used to obtain analytical expressions for the single (mode) and combination resonance instability regions. It is shown that other cases of the combination resonance can be of major importance and yield a significantly enlarged instability region in comparison to the principal instability region. The effects of nonuniform edge loading, centrally located circular cutout, damping, the static, and dynamic load factors on dynamic instability behavior of simply supported doubly curved panels are studied. The results show that under localized edge loading, combination resonance zones are as important as single (mode) resonance zones. The effects of damping show that there is a finite critical value of the dynamic load factor for each instability region below which doubly curved panels cannot become dynamically unstable. A central circular cutout has the destabilizing effect on the dynamic stability behavior of doubly curved panels subjected to nonuniform edge loading. This example of simultaneous excitation of two modes, each oscillating steadily at its own natural frequency, may be of considerable interest in vibration testing of actual structures. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.org/emo/resource/1/jenmdt/v134/i7/p555_s1?isAuthorized=no [article] Combination resonance instability of curved panels with cutout subjected to nonuniform loading with damping [texte imprimé] / Ratnakar. S. Udar, Auteur ; P. K. Datta, Auteur . - 2010 . - pp.555-566. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 134 N° 7 (Juillet 2008) . - pp.555-566 Mots-clés : Damping  Resonance  Vibration  Panels. Résumé : The dynamic instability of doubly curved panels with a centrally located circular cutout, subjected to nonuniform compressive in-plane harmonic edge loading is investigated. The present work deals with the problem of the occurrence of combination resonances in contrast to single (mode) resonances in parametrically excited doubly curved panels with a central circular cutout. The method of multiple scales is used to obtain analytical expressions for the single (mode) and combination resonance instability regions. It is shown that other cases of the combination resonance can be of major importance and yield a significantly enlarged instability region in comparison to the principal instability region. The effects of nonuniform edge loading, centrally located circular cutout, damping, the static, and dynamic load factors on dynamic instability behavior of simply supported doubly curved panels are studied. The results show that under localized edge loading, combination resonance zones are as important as single (mode) resonance zones. The effects of damping show that there is a finite critical value of the dynamic load factor for each instability region below which doubly curved panels cannot become dynamically unstable. A central circular cutout has the destabilizing effect on the dynamic stability behavior of doubly curved panels subjected to nonuniform edge loading. This example of simultaneous excitation of two modes, each oscillating steadily at its own natural frequency, may be of considerable interest in vibration testing of actual structures. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.org/emo/resource/1/jenmdt/v134/i7/p555_s1?isAuthorized=no

Combination resonance instability of curved panels with cutout subjected to nonuniform loading with damping / Ratnakar. S. Udar in Journal of engineering mechanics, Vol 134 n° 7 (Juillet 2008) 

Public ISBD [article]  in Journal of engineering mechanics > Vol 134 n° 7 (Juillet 2008) . - pp.555–566. Titre : Combination resonance instability of curved panels with cutout subjected to nonuniform loading with damping Type de document : texte imprimé Auteurs : Ratnakar. S. Udar, Auteur ; P. K. Datta, Auteur Année de publication : 2013 Article en page(s) : pp.555–566. Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Damping  Resonance  Vibration  Panels Résumé : The dynamic instability of doubly curved panels with a centrally located circular cutout, subjected to nonuniform compressive in-plane harmonic edge loading is investigated. The present work deals with the problem of the occurrence of combination resonances in contrast to single (mode) resonances in parametrically excited doubly curved panels with a central circular cutout. The method of multiple scales is used to obtain analytical expressions for the single (mode) and combination resonance instability regions. It is shown that other cases of the combination resonance can be of major importance and yield a significantly enlarged instability region in comparison to the principal instability region. The effects of nonuniform edge loading, centrally located circular cutout, damping, the static, and dynamic load factors on dynamic instability behavior of simply supported doubly curved panels are studied. The results show that under localized edge loading, combination resonance zones are as important as single (mode) resonance zones. The effects of damping show that there is a finite critical value of the dynamic load factor for each instability region below which doubly curved panels cannot become dynamically unstable. A central circular cutout has the destabilizing effect on the dynamic stability behavior of doubly curved panels subjected to nonuniform edge loading. This example of simultaneous excitation of two modes, each oscillating steadily at its own natural frequency, may be of considerable interest in vibration testing of actual structures. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%290733-9399%282008%29134%3A7%2855 [...] [article] Combination resonance instability of curved panels with cutout subjected to nonuniform loading with damping [texte imprimé] / Ratnakar. S. Udar, Auteur ; P. K. Datta, Auteur . - 2013 . - pp.555–566. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol 134 n° 7 (Juillet 2008) . - pp.555–566. Mots-clés : Damping  Resonance  Vibration  Panels Résumé : The dynamic instability of doubly curved panels with a centrally located circular cutout, subjected to nonuniform compressive in-plane harmonic edge loading is investigated. The present work deals with the problem of the occurrence of combination resonances in contrast to single (mode) resonances in parametrically excited doubly curved panels with a central circular cutout. The method of multiple scales is used to obtain analytical expressions for the single (mode) and combination resonance instability regions. It is shown that other cases of the combination resonance can be of major importance and yield a significantly enlarged instability region in comparison to the principal instability region. The effects of nonuniform edge loading, centrally located circular cutout, damping, the static, and dynamic load factors on dynamic instability behavior of simply supported doubly curved panels are studied. The results show that under localized edge loading, combination resonance zones are as important as single (mode) resonance zones. The effects of damping show that there is a finite critical value of the dynamic load factor for each instability region below which doubly curved panels cannot become dynamically unstable. A central circular cutout has the destabilizing effect on the dynamic stability behavior of doubly curved panels subjected to nonuniform edge loading. This example of simultaneous excitation of two modes, each oscillating steadily at its own natural frequency, may be of considerable interest in vibration testing of actual structures. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%290733-9399%282008%29134%3A7%2855 [...]

Parametric study on the dynamic instability behavior of laminated composite stiffened plate / Patel, S. N. in Journal of engineering mechanics, Vol. 135 N° 11 (Novembre 2009) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 135 N° 11 (Novembre 2009) . - pp. 1331-1341 Titre : Parametric study on the dynamic instability behavior of laminated composite stiffened plate Type de document : texte imprimé Auteurs : Patel, S. N., Auteur ; P. K. Datta, Auteur ; Sheikh, A. H., Auteur Article en page(s) : pp. 1331-1341 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Finite  element  method  Plates  Parameters  Stiffening. Résumé : This paper deals with the study of dynamic or parametric instability behavior of laminated composite stiffened plates with step-uniform and concentrated in-plane harmonic edge loading. The eight-noded isoparametric degenerated shell element and a compatible three-noded curved beam element are used to model the plate and the stiffeners, respectively. The method of Hill's infinite determinant is applied to analyze the dynamic instability regions. Numerical results are presented through convergence and comparison with the published results from the literature. The effects of parameters like loading type, stiffening scheme, lamination scheme, dynamic load factor, and boundary conditions are considered in the dynamic instability analysis of laminated composite stiffened plate. It has been shown that the type of loading and the width of loading have remarkable effect on the dynamic instability characteristics of the stiffened plate. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...] [article] Parametric study on the dynamic instability behavior of laminated composite stiffened plate [texte imprimé] / Patel, S. N., Auteur ; P. K. Datta, Auteur ; Sheikh, A. H., Auteur . - pp. 1331-1341. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 135 N° 11 (Novembre 2009) . - pp. 1331-1341 Mots-clés : Finite  element  method  Plates  Parameters  Stiffening. Résumé : This paper deals with the study of dynamic or parametric instability behavior of laminated composite stiffened plates with step-uniform and concentrated in-plane harmonic edge loading. The eight-noded isoparametric degenerated shell element and a compatible three-noded curved beam element are used to model the plate and the stiffeners, respectively. The method of Hill's infinite determinant is applied to analyze the dynamic instability regions. Numerical results are presented through convergence and comparison with the published results from the literature. The effects of parameters like loading type, stiffening scheme, lamination scheme, dynamic load factor, and boundary conditions are considered in the dynamic instability analysis of laminated composite stiffened plate. It has been shown that the type of loading and the width of loading have remarkable effect on the dynamic instability characteristics of the stiffened plate. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JENMDT000 [...]