Free flexural( or bending) vibrations analysis of doubly stiffened, composite, orthotropic base plates and panels (in aero-structural systems)

Download

index.pdf

Date

2003

Author

Çil, Kürşad

Metadata

Show full item record

Item Usage Stats

227
views

0
downloads

In this Thesis, the problem of the أFree Vibrations Analysis of Doubly Stiffened Composite, Orthotropic and/or Isotropic, Base Plates or Panels (with Orthotropic Stiffening Plate Strips)ؤ is investigated. The composite plate or panel system is made of an أOrthotropic and/or Isotropic Base Plateؤ stiffened or reinforced by adhesively bonded أUpper and Lower Orthotropic Stiffening Plate Stripsؤ. The plates are assumed to be the أMindlin Platesؤ connected by relatively very thin adhesive layers. The general problem under study is considered in terms of three problems, namely أMain PROBLEM Iؤ, أMain PROBLEM IIؤ and أMain PROBLEM IIIؤ. The theoretical formulation of the أMain PROBLEMSؤ is based on a أFirst Order Shear Deformation Plate Theory (FSDPT)ؤ that is, in this case, the أMindlin Plate Theoryؤ. The entire composite system is assumed to have simple supports along the two opposite edges so that the أClassical Levy̕s Solutionsؤ can be applied in that direction. Thus, the transverse shear deformations and the rotary moments of inertia of plates are included in the formulation. The very thin, yet elastic deformable adhesive layers are considered as continua with transverse normal and shear stresses. The damping effects in the plates and the adhesive layers are neglected. The sets of the systems of equations of the أMindlin Plate Theoryؤ are reduced to a set of the أGoverning System of First Order Ordinary Differential Equationsؤ in the أstate vectorؤ form. The sets of the أGoverning Systemؤ for each أMain PROBLEMؤ constitute a أTwo-Point Boundary Value Problemؤ in the y-direction which is taken along the length of the plates. Then, the system is solved by the أModified Transfer Matrix Method (with Interpolation Polynomials and/or Chebyshev Polynomials)ؤ which is a relatively semi-analytical and numerical technique. The numerical results and important parametric studies

Subject Keywords

Plates (Engineering), Vibration

URI

http://etd.lib.metu.edu.tr/upload/2/1062256/index.pdf
https://hdl.handle.net/11511/13714

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Sudden drop phenomena in natural frequencies of composite plates or panels with a central stiffening plate strip Yuceoglu, U; Ozerciyes, V (2000-06-01) The free bending vibrations of an orthotropic, composite base plate or panel reinforced by a central stiffening plate strip are considered. The orthotropic base plate and the dissimilar, orthotropic, central stiffening plate strip are bonded together with a very thin adhesive layer. The dynamic equations of the lower base plate and the upper stiffening strips are derived according to the 'Mindlin plate theory'. The governing system of partial differential equations is first reduced to a special set of first...
Free bending vibrations of integrally-stiffened and/or stepped-thickness rectangular plates or panels with a non-central plate stiffener Yuceoglu, U.; GEMALMAYAN, NİHAT; Sunar, O. (2007-11-16) The present study is primarily concerned with the "Free Bending Vibrations of Integrally-Stiffened and/or Stepped-Thickness Plates or Panels with a Non-Central Plate Stiffener". The general theoretical formulation is based on the "Mindlin Plate Theory". The plate elements of the system are considered to be made of dissimilar orthotropic materials with unequal thicknesses. The transverse shear deformations and the transverse and the rotary moments of inertia of plate elements are included in the analysis. Th...
Free flexural (or bending) vibrations analysis of composite, orthotropic plate and/or panels with various bonded joints(--- in aero structural systems---) Güvendik, Özen; Yüceoğlu, Umur; Department of Aerospace Engineering (2004) In this أThesisؤ, the problems of the أFree Flexural (or Bending) Vibrations of Composite, Orthotropic Plates and/or Panels with Various Bonded Jointsؤ are formulated and investigated in detail. The composite bonded plate system is composed of أPlate Adherendsؤ adhesively bonded by relatively very thin adhesive layers. The general problem is considered in terms of the three أMain PROBLEMSؤ, namely أMain PROBLEM Iؤ, أMain PROBLEM IIؤ and أMain PROBLEM IIIؤ. The theoretical formulation of the أMain PROBLEMSؤ ...
Vibration characteristics of various wide flange steel beams and columns Özel, Halil Fırat; Sarıtaş, Afşin; Tasbahjı, Tayseer (null; 2015-12-11) Vibration characteristics of steel framed structures are affected by accurate modelling of the mass and stiffness matrices of beam and column members. In this regards, wide flange sections are the most popularly used steel sections, and calculation of axial, flexural and shear responses of these sections become critical. In this study, a mixed formulation frame finite element is developed from three-fields Hu-Washizu-Barr functional. Consistent mass matrix of the element is obtained such that determination ...
Robustness Analysis of Intentional Mistuning Patterns in Randomly Mistuned Bladed Disk Assemblies Yumer, M. E.; Ciğeroğlu, Ender; Özgüven, Hasan Nevzat (2010-09-22) It is known that bladed disks, which are usually designed as cyclically symmetric structures, undergo considerable amount of forced response amplitude magnification due to the phenomenon called mistuning. Mistuning is inevitable for any cyclically symmetric bladed disk assembly since it is caused by manufacturing tolerances, material properties and operational wear. Since reducing the level of mistuning beyond certain limits is not possible with the current technology, the attempts are rather made to reduce...

Citation Formats

K. Çil, “Free flexural( or bending) vibrations analysis of doubly stiffened, composite, orthotropic base plates and panels (in aero-structural systems),” M.S. - Master of Science, Middle East Technical University, 2003.