Engineering applications of electro-rheological fluids

The use of electro-rheological (ER) fluids is relatively new in engineering applications.\ud ER fluids can change from liquid to solid-like gel under an electrical field, and this\ud change takes place within milliseconds. The change is reversible once the electrical field\ud is removed. This thesis is an experimental investigation to deal with three particular\ud engineering applications of ER fluids. The first application is improving the vibration\ud control characteristics of a conventional tuned absorber using an ER fluid as the working\ud fluid of the absorber. The second application is to demonstrate the same ER fluid's ability\ud to couple two discs for power transmission. This concept is similar to the operation of a\ud clutch or direct coupling device between rotating machinery. The third application is of\ud more exploratory type. It deals with switching the shape of an airfoil in flight between\ud two different profiles. The purpose of such switching action is to exploit different\ud aerodynamic properties of two different profiles, ultimately leading to a simple design for\ud improved flight safety