Showing papers by "M. Ganapathi published in 2007"

Nonlinear Dynamic Thermal Buckling of Functionally Graded Spherical Caps

Abstract: isotropic/orthotropic/functionally graded material spherical shells suddenly exposed to thermal environment is rather meager in the literature and such studies are important to the structural designers. In the present work, the nonlinear dynamic thermal buckling of functionally graded spherical caps is investigated using a threenoded shear flexible axisymmetric curved shell element based on field-consistencyprinciple[6].Geometricnonlinearityisassumedin thepresentstudy,usingvonKarman’sstrain-displacement relations. In addition, the formulation includes in-plane and rotary inertia effects. The material properties are graded in the thickness direction according to the power-law distribution in terms of volume fractions of the constituents of the material. The nonlinear governing equations derived are solved employing Newmark’s numerical integration method in conjunction with the modified Newton– Raphson iteration scheme. The critical dynamic buckling temperature difference is taken as the temperature difference between the shell surfaces corresponding to a sudden jump in the maximum average displacement in the time history [2,12]. Numerical results arepresented that considerdifferent values ofgeometrical parameter and power-law index.