INVESTIGATING OF THE CRITICAL THERMAL BUCKLING LOAD OF LINEAR FUNCTIONALLY GRADED RECTANGULAR FIN

Abstract

This study investigates the critical buckling due to heat Load of rectangular functionally graded material fins (FG-Fins) under uniform temperature conditions. This study differs from traditional studies by looking at graded properties in the axial direction. In this case, the mechanical and thermal properties (modulus of elasticity, Poisson ratio and thermal expansion coefficient) were graded in the length direction of the fins, which in this study the upper surface of the fins were considered to be pure copper. A finite element model in three dimensions was created in ANSYS APDL with the 10-node tetrahedral element (SOLID87) using a stepped-property approach. Fixed–Fixed and Simply Supported–Fixed boundary conditions were exposed to stepwise static thermal analysis followed by eigenvalue buckling analysis. The model which was validated against published studies showed a high agreement with the error of less than 5.654%. The critical thermal buckling Load was seen to rise with reduced length-to-width ratios and increased elasticity modulus ratios. Under axial gradation of mechanical properties, the effect of thermal stability was more significant than the effect of geometric aspect ratios. Fixed–Fixed condition showed the highest buckling resistance comparing with Simply Supported–Fixed condition. While the variation of length-to-width ratios were paramount in determining the form of higher modes.