Aerodynamic damping and amplitude response of piezoelectric fans in free and confined space

Abstract

The main objective is to develop a predictive model to directly predict and describe the sensitivity of aerodynamic damping and amplitude response to the proximity of surrounding walls. To achieve the objective of this study, the instantaneous fluid force loaded on the vibrating cantilever in free space and confined space are numerically studied. The correlation mechanisms between the unsteady flow characteristics and the aerodynamic damping are also discussed. It can be concluded that the fluid structure interactions can be attributed to the change in viscous damping when the vibrating cantilever approaches the solid wall. Based on Newton’s law of viscous fluid, a fluid flow model is developed to estimate the additional fluid force generated between the cantilever and the sidewall. The new developed predictive model for aerodynamic damping and amplitude response are validated, and the results show that there is a good agreement with the experimental results. The developed model provides an important tool for the prediction of damping and amplitude to help implement piezoelectric fans in practical confined physical space.

Keywords

• piezoelectric fans
• vibrating cantilevers
• aerodynamic damping
• flow structure interaction