Temporally-resolved hydrodynamics in the vicinity of a vibrating ionic polymer metal composite

Abstract

In this paper, we study the hydrodynamics induced by an ionic polymer metal composite (IPMC) cantilever vibrating in a quiescent fluid. Time-resolved particle image velocimetry is used to measure the velocity field in the vicinity of the vibrating IPMC strip and a control volume analysis is utilized to estimate the thrust production per unit IPMC width. The governing fluid dynamics dimensionless parameters are varied parametrically to ascertain the influence of the Reynolds number, the peak tip displacement to IPMC length ratio, and the IPMC aspect ratio. It is found that the Reynolds number is the dominant parameter in determining the thrust produced by the IPMC, while the relative tip displacement and aspect ratio play secondary roles. An increase in the relative tip displacement has a minimal effect on the produced thrust, while an increase in the aspect ratio results in a mild decrease in thrust production. It is further found that estimating the thrust from the mean velocity field significantly underpredicts the thrust estimate.