A Continuum Theory for Wave Propagation in Laminated Composites—Case 1: Propagation Normal to the Laminates

1973 ◽  
Vol 40 (2) ◽  
pp. 503-510 ◽  
Author(s):  
G. A. Hegemier ◽  
Adnan H. Nayfeh
Keyword(s):  
Wave Propagation ◽  
Continuum Theory ◽  
Laminated Composite ◽  
Velocity Spectrum ◽  
Model Accuracy ◽  
Standard Mixture ◽  
Exact Data ◽  
Dispersive Model ◽  
Estimate System ◽  
Hierarchy Of Models

A continuum theory is developed for wave propagation normal to the layers of a laminated composite with elastic, periodic, microstructure. Construction is based upon an asymptotic scheme in which dominant signal wavelengths are assumed large compared to typical composite microdimensions. A hierarchy of models are defined by the order of truncation of the asymptotic sequence obtained. To estimate system accuracy, the phase velocity spectrum is investigated. Retention of all terms in the asymptotic sequence is found to yield the exact spectrum of Rytov. Based upon spectral collation of the lowest-order dispersive model, accuracy superior to several existing theories is observed. In addition, treatment of transient pulse cases show good correlation with exact data. Finally, the lowest-order dispersive theory is cast in a standard mixture form.

A General Continuum Theory With Microstructure for Wave Propagation in Elastic Laminated Composites

1974 ◽  
Vol 41 (1) ◽  
pp. 101-105 ◽  
Author(s):  
G. A. Hegemier ◽  
T. C. Bache
Keyword(s):  
Wave Propagation ◽  
Continuum Model ◽  
Laminated Composites ◽  
Continuum Theory ◽  
Velocity Spectrum ◽  
Two Dimensional ◽  
One Dimensional ◽  
General Continuum ◽  
Hierarchy Of Models ◽  
Dimensional Wave

A continuum theory with microstructure for wave propagation in laminated composites, proposed in previous works concerning propagation normal and parallel to the laminates, is extended herein to the general two-dimensional case. Continuum model construction is based upon an asymptotic scheme in which dominant signal wavelengths are assumed large compared to typical composite microdimensions. A hierarchy of models is defined by the order of truncation of the obtained asymptotic sequence. Particular attention is given to the lowest order dispersive theory. The phase velocity spectrum of the general theory is investigated for one-dimensional wave propagation at various propagation angles with respect to the laminates. Retention of all terms in the asymptotic sequence is found to yield the exact elasticity spectrum, while spectral collation of the lowest order dispersive theory with the first three modes of the exact theory gives excellent agreement.

Thermally Induced Stress Waves in a Laminated Composite

1972 ◽  
Vol 39 (1) ◽  
pp. 103-107
Author(s):  
C. Sve
Keyword(s):  
Temperature Distribution ◽  
Half Plane ◽  
Continuum Theory ◽  
Laminated Composite ◽  
Stress Waves ◽  
Internal Heating ◽  
Thermally Induced ◽  
Electromagnetic Absorption ◽  
Induced Stress ◽  
Dispersive Model

A solution is presented for the response of a periodically laminated elastic half plane subjected to rapid internal heating. The assumed temperature distribution has been used in previous investigations of electromagnetic absorption problems where thermal diffusion may be neglected. The laminations are perpendicular to the free surface of the half plane, and the incident flux is absorbed in each layer according to an exponential decay with depth. Since heal conduction is neglected on this time scale, the temperature distribution is discontinuous at the lamination interfaces. A microstructured continuum theory provides the dispersive model, and a solution is obtained for the composite stress in the far field. Limiting forms of the solution are included for the cases when the radiation is absorbed in the alternate layers only or when dispersion can be neglected. Several numerical examples are presented to illustrate the effect of dispersion.

A Spectral Finite Element Model for Wave Propagation Analysis in Laminated Composite Plate

2006 ◽  
Vol 128 (4) ◽  
pp. 477-488 ◽  
Author(s):  
A. Chakraborty ◽  
S. Gopalakrishnan
Keyword(s):  
Finite Element ◽  
Wave Propagation ◽  
Shear Deformation ◽  
Mechanical Response ◽  
Laminated Composite ◽  
Wave Number ◽  
Single Element ◽  
Element Formulation ◽  
Frequency Wave ◽  
Spectral Finite Element

A new spectral plate element (SPE) is developed to analyze wave propagation in anisotropic laminated composite media. The element is based on the first-order laminated plate theory, which takes shear deformation into consideration. The element is formulated using the recently developed methodology of spectral finite element formulation based on the solution of a polynomial eigenvalue problem. By virtue of its frequency-wave number domain formulation, single element is sufficient to model large structures, where conventional finite element method will incur heavy cost of computation. The variation of the wave numbers with frequency is shown, which illustrates the inhomogeneous nature of the wave. The element is used to demonstrate the nature of the wave propagating in laminated composite due to mechanical impact and the effect of shear deformation on the mechanical response is demonstrated. The element is also upgraded to an active spectral plate clement for modeling open and closed loop vibration control of plate structures. Further, delamination is introduced in the SPE and scattered wave is captured for both broadband and modulated pulse loading.

Wave propagation in laminated composite plates

1988 ◽  
Vol 83 (6) ◽  
pp. 2020-2026 ◽  
Author(s):  
S. K. Datta ◽  
A. H. Shah ◽  
R. L. Bratton ◽  
T. Chakraborty
Keyword(s):  
Wave Propagation ◽  
Laminated Composite ◽  
Composite Plates ◽  
Laminated Composite Plates
Sign in / Sign up

Export Citation Format

Share Document