Optimal design and large amplitude vibration of SiCf/SiC composite straight/curved gas turbine blade

This study presents a computational framework for analysing the large amplitude vibration characteristics and parametric optimisation of rotating SiC f / SiC ceramic matrix composite blades maintained at high temperature, which is applicable for gas turbine technology. A finite element-based nonlinear model is developed using higher-order shear-deformation theory-based Green-Lagrange strain field, providing an accurate representation of rotating gas turbine blades. Here, the dynamic equations of motion are derived using Hamilton’s principle, considering moderate rotational speeds. The accuracy of the developed model is validated through comparisons with existing literature. A detailed parametric study explores the influence of geometric factors such as aspect ratio, thickness ratio, twist angle, hub-span ratio, and rotational speed on the small-to-large amplitude vibrational responses. Additionally, to determine the optimal design parameters for maximising the fundamental frequency of the blade, a response surface methodology-based optimisation approach with central composite rotatable design is employed. The findings contribute to the computational design and structural optimisation of high-performance rotating components in turbomachinery applications.