Tunable viscosity of photo-rheological fluids and its application to structural damping control

This research presents a state-of-art smart fluid for vibration control. A new class of photo-rheological (PR) fluid whose rheological behavior can be changed by ultraviolet (UV) light is proposed by mixing with luminescence microparticles to enhance the rheological properties. When the PR fluid was exposed to UV light, the viscosity of PR fluid becomes decreased, while viscosity recovered its initial value when UV light was turned off, which implies that the viscosity of PR fluid can be reversible, and variable. The main advantages of PR fluid application are no deposition due to single solution, and no EMI environment because of using only UV light. We will demonstrate that the viscosity changes of PRFs can be induced by UV light, and can successfully apply to semi-active damping control of vibrating structures.