Carbon-nanotube-based structural health monitoring for wind turbine applications

This paper presents a study on incorporation of carbon nanotubes (CNTs) in fiber-reinforced plastics for potential real-time structural health monitoring. CNTs dispersed in a solvent were uniformly spray-coated on the surfaces of glass fiber textile plies, which were then layed-up and impregnated with unsaturated polyester resin using vacuum-assisted resin transfer molding to form a 150 mm by 150 mm composite panel. Prior to resin infusion, electrodes were embedded on the periphery as well as between the plies for resistance monitoring. The composite panel was subjected to three-point bending, during which the changes in resistances between various electrode pairs were measured and recorded. Experimental results revealed the dependence of resistance change measurements on the loading conditions, amount of CNTs coated, measured directions, and presence of structural failure. The proof-of-concept was demonstrated by fabricating and testing with a miniaturized wind turbine blade.