Vibrational Response of Twisted Ceramic Matrix Composite Blades with Carbon Nanotube Reinforcement: A Parametric and RSM Approach

Abstract

This study examines the vibrational behaviour of rotating twisted blades made from ceramic matrix composites reinforced with carbon nanotubes. Three carbon nanotubes distribution patterns, namely uniform, outer-rich, and inner-rich are analysed to evaluate their effect on blade dynamics. Effective material properties are estimated using an extended Voigt model and applied within a first-order shear deformation theory framework. The governing equations, derived using Hamilton’s principle, are solved through a two-dimensional finite element method with eight-noded Serendipity elements. Validation against benchmark results confirms the accuracy of the formulation. Parametric analysis shows that carbon nanotubes reinforcement improves stiffness and increases the non-dimensional frequency, with the inner-rich distribution providing the best performance. Mode veering and frequency crossover are influenced by geometry and rotational speed. Optimisation using response surface methodology further enhances the fundamental frequency, highlighting the potential of carbon nanotubes-reinforced composites in high-performance rotating blade applications.