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In this paper the stability of a rectangular plate in a supersonic flow in the presence of a temperature field, inhomogeneous across the thickness, is investigated. The temperature field inhomogene...

The thermo-mechanical vibration characteristics of doubly-curved nano-composite shells reinforced by graphene nanoplatelets are investigated by considering a uniform distribution of graphene and a first-order shear deformation theory. The mechanical properties of the nano-composite shells are estimated by using the modified HalpinTsai model. The governing equations are first derived by a variational formulation using Hamiltons principle and are solved using the Galerkin technique. Numerical results are presented for various shell curvatures and compared with those available in the archival literature. Furthermore, parametric studies are offered to highlight the significant influence of graphene nanoplatelets weight fraction, dimensions of graphene nanoplatelets, and temperature variation, on the free vibration of the nano-composite shells.

This article provides new insights into the aerothermoelastic stability of thin plates. Particularly, the issue of loss of stability of an isotropic plate-strip of constant thickness immersed in a supersonic flow field and subjected to a variable temperature field through the thickness is examined. Using the basic principles of the theory of aerothermoelasticity of isotropic bodies, the theories of flexible panels, and the linear law of temperature field through the thickness of the panel, the stability equations and associated boundary conditions are obtained. As expected, the coefficients of the aerothermoelastic governing equations depend on the thermal load, and consequently the panel-flutter critical speed depends on temperature. The model takes into account quadratic and cubic aerodynamic non-linearities as well as cubic geometric non-linearities. Due to the inhomogeneity of the temperature field distribution across the thickness plate buckling instability occurs. This instability accounts for the d...

This paper discusses the theory of thermo-conductivity due steady-state heat flow of semi-infinite homogeneous solids containing a perfectly rigid circular inclusion located on the plane where the two half-solids are joint. The half-spaces have different thermo-physical characteristics and a steady heat flow is applied to the solids. The effects of selected spatial heat sources are also investigated. Mathematical model and general solution is presented along with selected particular cases and simulations, followed by pertinent discussions and conclusions.

Functionally Graded Materials (FGM) have attracted significant interest as heat-shielding materials for space vehicle, skin sub-structures, gas turbine blades technologies, and many other high-temperature industrial applications. This paper reviews the state-of-the-art in linear and nonlinear aero-thermo-elasticity of FGM panels with emphasis on the authors’ contributions to the topic. An overview of the pertinent literature discussing the linear and nonlinear behavior of flat and curved panels when exposed to high temperature supersonic flow fields is presented first. The effect of material property dependency on temperature is also discussed. The study addresses divergence and flutter and methodologies used to determine these aero-thermo-elastic instabilities. In particular, critical and post-critical behaviors for panels in presence of thermal loads are addressed, along with a series of divergence, flutter, and post-flutter results obtained with linear/nonlinear dynamics approaches. Regular and chaotic...

This paper deals with the thermally induced dynamic response analysis of a composite blade rotating at a constant speed. Fiber-reinforced composite thin-walled beam are used in a variety of aerospace applications, including helicopter rotor blades, tilt rotor aircraft, turbine engines, compressor blades, only to name a few. The composite beam is modeled as a tapered thin-walled beam which is subjected to a temperature field. A number of non-classical features such as transverse shear, secondary warping, anisotropy of constituent materials, and rotary inertias have been included in the model. The structure of the blade consists of a host graphite epoxy laminate with spanwise distributed transversely isotropic (PZT-4) sensors and actuators. The discussed results reveal that the thermal environment has a detrimental effect on the blade dynamic response. The active controller is implemented via the combined displacement and velocity feedback control methodology, which can alleviate the deleterious effect asso...