دانلود رایگان مقاله آنالیز حرارتی صفحات FGM - نقد تکنیک های مختلف مدل سازی

Abstract

Functionally Graded Materials (FGMs) are the advanced materials in the field of composites, which can resist high temperatures and are proficient in reducing the thermal stresses. In recent decades, significant investigations are reported in the predicting the response of FGM plates subjected to thermal loads. This paper presents a comprehensive review of developments, applications, various mathematical idealizations of materials, temperature profiles, modeling techniques and solutions methods that are adopted for the thermal analysis of FGM plates. An attempt has been made to classify the various analytical and numerical methods used for the stress, vibration and buckling analyses of FGM plates under one-dimensional or three-dimensional variation of temperature with constant/linear/nonlinear temperatures profiles across the thickness. An effort has been made to focus the discussion on the various research studies carried out till recently for the thermal analysis of FGM plates. Finally, some important conclusions and the suggestions for future directions of research in this area are presented. It is felt that this review paper will serve the interests of all the academicians, researchers and engineers involved in the analysis and design of FGM plates.

7. Conclusions

A review of progressive developments in the thermal stress, vibration and buckling analyses of single/multi-layered FGM and sandwich plates are presented. Most of the theories/computational models employed for the analysis of composite laminates/isotropic plates are extended for FGM plates. Three dimensional elasticity solutions were found to be the most accurate solutions for thermal analysis of FGM plates. Due to the mathematical complexity involved the studies are restricted to analytical methods with only simply supported edges or clamped edges. Most of the three dimensional solutions that are reported on stress analysis of FGM plates have adopted three dimensional distribution of temperature variations for thermal analysis, whereas vibration and buckling analyses limits to one-dimensional variation of temperature distribution. Hence, exact solutions for thermal vibration and buckling analyses are still not available. Exact three dimensional solutions using power law function has not been dealt. Also, 3D solutions including geometric nonlinear effects and temperature dependent variations in material properties are not reported yet. The computational effort and cost involved is very high for 3D analysis and hence development of most accurate solution methods based on approximate methods/2D theories is gaining attention by researchers. Most of the 2D plate theories like CLPT, FSDT, HSDT, TSDT, CUF, non-polynomial based refined plate theories, etc., have considered only the effect of transverse shear deformation in predicting the global responses of FGM plates, while only few displacement models have focused on including the effect of both transverse shear and transverse normal deformations. It has to be noted that the assumption of constant transverse deflection in 2D plate theories were found to be invalid for thermal analysis of FGM plates and thus the effect of higher order transverse displacement terms have to be employed for accurate prediction of responses. Among the available 2D theories, FSDT, R-TSDT and HSDT have been discussed widely in literature for various plate geometries, temperatures, initial imperfections and boundary conditions. Few semi-analytical computational models are also developed for the thermal analysis of FGM plates based on state-space method, asymptotic method, DRQ technique, etc. These methods are extended for numerical methods like FEM and meshless methods, and hence found to be consistent.