Structural Design Optimization of Composite Rotor Blades with Strength Considerations

Structural design optimization of composite helicopter rotor blades through numerical analysis is a challenging task. Among many studies in the past, strength properties and failure conditions of composite structures are generally neglected. With advanced composite analysis tools, many composite structures these days can be further optimized with even less weight and cost but still satisfying the given design requirements. However, safety considerations and the lack of proper composite stress/failure analysis usually make the final structure overly conservative and not cost effective. In this study, VABS will be used to consider the failure analysis in a design optimization process of a composite helicopter rotor blade, thanks to the fast and accurate layerwise three-dimensional stress prediction. Then VABS will be integrated into the Galaxy framework and connected with RCAS to achieve local-global design optimization of the blade. Numerical examples using the UH-60A helicopter are presented to show the capability of the toolset to design advanced composite rotor blades considering mechanical requirements in terms of inertial, stiffness and strength properties.