We examine if signals emanating from sensors measuring aerodynamic quantities (e.g. aerodynamic pressure over an airfoil section) can be used to detect structural damage (e.g. crack) on a long and slender aeroelastic structure (e.g. wind turbine blade). This work was motivated by current efforts on development of a novel micro-electro-mechanical monitoring system based on aerodynamic surface pressure and aero-acoustic measurements for structural health monitoring of wind turbine blades, as part of the Aerosense project (https://www.aerosense.ai/). Sensing nodes are distributed along the span of the blade, delivering measurements of local sectional aerodynamic pressure distributions and aero-acoustic and acceleration signals. Assuming the availability of such a monitoring system, we explore our proposition via an experimental setup, an analytical aeroelastic numerical model and an unsteady Fluid-Structure-Interaction model in Comsol. The experimental and simulations setup consist of a 180cm long slender Aluminium beam, and a 3D printed airfoil section assembled to the mid-span of the beam. The beam is excited with a rotating imbalanced mass at the tip and a fan is used in front of the setup as a source of wind loading as well. The airfoil section is partially soft allowing for static morphing. Damage is introduced on both the beam and the 3D printed airfoil section. We compare our proposition of damage detection via aerodynamic pressure vs a vibration based a damage detection approach. Our initial results indicate that structural damage could indeed be identified via aerodynamic pressure signals, for an aero-structural coupled system.

Tag: "aerodynamic"

detecting structural damage using aerodynamic quantities