Composite chiral shear vibration damper

The work describes a structural composite damper concept based on a chiral auxetic configuration. Chiral structures couple uniaxial and rotational deformations to provide a negative Poisson’s ratio behaviour and high dissipation through shear strain energy, and this feature is exploited by up-scaling the deformation mechanism of the chiral cell to design a damper that dissipates energy in the edgewise/shear modes, like the ones occurring in wind turbine blades. The damper concept and its configuration are evaluated through a series of Finite Element parametric and probabilistic models. A small-scale demonstrator is manufactured and subjected to compressive cyclic loading at increasing maximum displacements. Good agreement between the numerical and experimental force–displacement and energy dissipated-displacement curves is observed, showing the feasibility of the chiral composite damper concept for vibration damping-related applications at low frequencies.