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In the present work thermal buckling of symmetric cross-ply composite laminates is investigated. In this study, a square plate element is employed for the thermal buckling analysis of composite laminated plates. The maximum buckling temperature of symmetric cross-ply laminates under various sides to thickness ratios, aspect ratios, stacking sequence and boundary condition are studied in detail. The maximum buckling temperature analysis of square composite eight and four layered plates under uniform temperature rise is investigated using the classical laminated plate theory & first order shear deformation theory and material properties (Stiffnesses, Poisson’s ratio and Coefficient of thermal expansion) are considered to be temperature dependent. The classical laminated plate theory and first order shear deformation theory in conjunction with the Rayleigh-Ritz method is used for the evaluation of the thermal buckling parameters of structures made out of graphite fibers with an epoxy matrix. The post-buckling response of symmetrically cross-ply laminated composite plates subjected to a combination of uniform temperature distribution through the thickness and in-plane compressive edge loading is presented. The maximum buckling temperature is obtained from the solution. The computing is done by using MATLAB.

This article reports on development, characterization, and performance of liquid-treated nonwoven air filter media for automotive engine intake application. A polypropylene fiber-based needle-punched nonwoven fabric was prepared for treatment with four viscous liquids (glycerol, SAE 20W/50 engine oil, PEG 400, and deionized water) by liquid spraying technique. The filtration performance was evaluated in terms of initial and final gravimetric filtration efficiencies, fractional filtration efficiency, evolution of pressure drop, and dust holding capacity. The liquid-treated filter media registered higher gravimetric as well as fractional filtration efficiency and higher dust holding capacity as compared to the untreated ones. The initial and final gravimetric filtration efficiencies were found to be directly related to liquid add-on via a power law relationship. The liquid-treated filter media also exhibited higher fractional filtration efficiency than their untreated counterparts for all sizes of tested particles. Interestingly, the increase of fractional efficiency was more for smaller particles as compared to larger ones. This was explained quantitatively through single fiber efficiency due to adhesion. The viscosity of liquid was found to be a very crucial parameter as the dust deposition morphology was contingent to the flow of liquid onto the filter media. The stickiest liquid yielded highest filtration efficiencies, displayed slowest rise of pressure drop, and exhibited highest dust holding capacity.