Concepts for morphing airfoil sections using bi-stable laminated composite structures

The present paper investigates the potential of using bi-stable laminated composite structures for morphing an airfoil section. The objective of the paper is to identify geometries and lay-ups of candidate configurations that offer multiple stable shapes for the airfoil section. Carbon-fiber laminated composites with non-symmetric laminate configurations are used for morphing the airfoil section. Thermal curing is used to induce residual stresses into the structure in order to achieve bi-stability. Three concepts that focus on morphing a flap-like structure and the camber and chord of an airfoil section are proposed. Several geometries and laminate configurations are investigated using finite element nonlinear static analysis. The magnitude of loads required to actuate the airfoil section between the stable shapes is evaluated. The impact of manufacturability on producing viable morphing mechanisms within the airfoil section is also discussed.