Influences of hygrothermal environment and installation mode on vibration characteristics of a rotating laminated composite beam

Flapwise vibration characteristics of a rotating laminated composite beam under hygrothermal environment are studied in this paper. The governing equation of the flapwise vibration for the rotating beam under hygrothermal environment is obtained applying D'Alembert's principle, in which the design parameters such as setting angle and pitch angle are considered. A numerical method based on Green's function to handle the vibration characteristics problem of a rotating composite beam is developed. Influences of the hub radius, rotating speed, pitch angle, setting angle, fiber orientation angles, temperature and humidity on natural frequencies of the rotating laminated composite beam are discussed. Results indicate that: (1) the rotating speed, hub radius, setting angle, pitch angle and fiber orientation angle have more prominent effects on natural frequencies than the temperature variation and moisture concentration do; (2) the influences of some parameters such as the hub radius, rotating speed, setting angle and pitch angle on the vibration characteristics are not independent, but coupled with each other.