FLEXIBLE ROTATING BEAM - COMPARATIVE MODELING OF ISOTROPIC AND COMPOSITE-MATERIAL INCLUDING GEOMETRIC NONLINEARITY

A comparative modelling of a flexible rotating beam has been considere d in this study. The dynamic model is based on a beam with either isot ropic material or composite material. The composite beam is considered as orthotropic fiber-reinforced and symmetrically laminated. Both sma ll linear as well as geometric non-linear deformations are studied. A continuous system is considered in the analytical approach. Both axial and transverse deformations are included, and they are represented by the mode shape functions of the beam. The coupled effect between the rigid body motion and the flexible motion is also considered. A forwar d dynamic numerical simulation is performed for a prescribed driving t orque on a steel and graphite/epoxy beam. The influence of flexibility on the rigid body motion is presented and discussed. From the numeric al results, the composite material has a lower energy consumption due to lower material density. It performs well in damping the vibration o f the structure due to its higher stiffness-to-weight ratio.