Size‐dependent nonlinear transient analysis of rotating porous thick and thin FGM microblade under cooling thermal shock

Abstract

The present work is an attempt to develop a simple, accurate, and widely applicable finite element formulation for the size‐dependent nonlinear transient analysis of the rotating porous thick and thin functionally graded material (FGM) microblade subjected to load due to centrifugal force and cooling thermal shock. First‐order shear deformation theory in conjunction with von Karman‐type nonlinearity is used in the development of the finite element formulation. The temperature‐dependent material properties of the SUS304 stainless steel and the AISI 1020 carbon steel are taken. The upper layer made of the SUS304 stainless steel is subjected to a cooling thermal shock and the lower layer made of AISI 1020 carbon steel is held constant at room temperature. The governing differential equation for the present analysis is obtained using total Lagrangian formulation in conjunction with the modified coupled stress theory (MCST). Modified Newton–Raphson in conjunction with Newmark average acceleration method is used to obtain the nonlinear transient response of the rotating porous FGM pretwisted blade. The results obtained from the present finite element formulation are first compared for a wide range of parameters. New results are presented to investigate the effect of porosity, intensity of the thermal shock, material scale ratio, rotational velocity, and volume fraction index on the nonlinear transient analysis of a rotating porous thick and thin SUS304/AISI 1020 functionally graded rotating blade under load due to centrifugal force and cooling thermal shock.