<title>Experimental investigation on the characteristics of a class of hydrous electro-rheological fluids and macroscopically smart beamlike structures featuring this class of colloidal suspensions</title>

Abstract

This experimental investigation is focused on characterizing a class of electro-rheological (ER) fluids and also characterizing a class of smart structures featuring this class of suspensions. These studies involved the imposition of different applied voltages on the ER fluid domain and various concentrations of the suspension particles. Electro-rheological fluids belong to a class of colloidal suspensions whose global characteristics can be controlled by the imposition of an appropriate external electric field upon the fluid domain. Therefore, when these fluids are embedded within a smart beam-like structure, the global properties of the beam, and hence its vibrational response, can also be controlled. In this work, the energy dissipation characteristics of smart cantilever beam specimens were measured. Different ER fluid smart beam specimens with various concentrations were employed in these investigations to provide insight on the relationship between the particle concentration of the suspension with damping ratio of the smart beam and the electric field intensity imposed on the beam. The coupled electrical and mechanical dynamic properties of smart materials featuring hydrous ER fluids were experimentally studied using a Rheometrics RMS 800 mechanical spectrometer to gain insight into their effectiveness in vibration control applications. THe experimental results demonstrate the non-Newtonian rheological behavior of ER fluids, and the ability of this class of smart beams to dissipate energy increases with the increase of particulate concentration and also the applied electric field.