ADVANCED FINITE-ELEMENT MODELING OF ROTOR BLADE AEROELASTICITY

An advanced beam finite element has been developed for modeling rotor blade dynamics and aeroelasticity. This element is part of the Element Library of the Second Generation Comprehensive Helicopter Analysis Sy stem (2GCHAS). The element allows modeling of arbitrary rotor systems, including bearingless rotors. It accounts for moderately large elasti c deflections, anisotropic properties, large frame motion for maneuver simulation, and allows for variable order shape functions. The effect s of gravity, mechanically applied and aerodynamic loads are included. All kinematic quantities required to compute airloads are provided. I n this paper, the fundamental assumptions and derivation of the elemen t matrices are presented. Numerical results are shown to verify the fo rmulation and illustrate several features of the element.