Free-vibration analysis of space vehicle structures made by composite materials

This work investigates the effects of composite materials and non-structural masses on the dynamic behavior of space structure components and whole space vehicle. A refined one-dimensional model has been used in the analyses, and the effects of composite materials and of the fuel mass introduced as non-structural masses have been considered. The adopted refined one-dimensional Finite Element Model has been developed using the Carrera Unified Formulation. This numerical tool allows to develop a variable kinematic displacement field over the beam cross-section, that is, a set of Lagrange (LE) expansions polynomials was adopted for the cross-sectional displacement field approximation. The use of such one-dimensional models leads to the so-called component-wise (CW) approach in which stiffeners and plate are modeled using the same one-dimensional kinematic. Static and free vibration analysis of space structural components and complete space structures have been performed. Both compact and thin-walled structural configurations have been considered. The results have been assessed using analytical solutions or refined three-dimensional Finite Element Models. Composite materials and non-structural masses, e.g. the fuel mass or payload, have been included in the analysis. The results show the capability of the present model to provide a quasi three-dimensional solution with a low computational cost. The refined kinematic allows composite materials to be investigated accurately.