Aero-hygrothermal effects on stability regions for functionally graded panels

This paper presents the aero-hygrothermal stability and nonlinear flutter behaviors of functionally graded panels. In this regard, the elastic, thermal and moisture expansion coefficients of the model vary continuously through the thickness directions in the volume fractions. For more effective evaluations of the material properties, Mori-Tanaka scheme is employed with respect to power-law (P-) and sigmoid (S-) models. Applying the principle of virtual work, governing equations of motion are derived. To check the validity of present works, results are compared with previous data. Especially, the aero-hygrothermal stability regions are compared based on the P- and S-FGMs for various ranges of the temperature, moisture and volume fraction index. Finally, the nonlinear dynamic behaviors of the models are investigated using Newmark time integration method in the stability regions.