유동 모드 하에서 ER 유체의 빙햄 특성에 대한 연구

A Study on the Bingham Properties of an ER Fluid under Flow Mode

This experimental study presents Bingham properties under the flow mode. Among working modes of ER fluids the flow mode is considered in this study. In order to undertake this work, a flow mode type electro-viscometer is manufactured. The experimental setup is similar to the ER damper which is operated by the double-rod hydraulic cylinder. The electrode gap is chosen by 1.00㎜. The pressure drops in the viscometer are measured by two pressure sensors at each end of the electrode. The yield stresses are then obtained through analytical procedures. As for the ER fluid to be tested, two types of ER fluids are employed; soluble-arabic gum based ER fluid(I3S50), an ER fluid of Bayer. The first one is composed in-housingly. The pressure drops of ER fluids are measured by increasing the electric field from zero to maximum voltage in room temperature. Consequently, the yield stresses of the ER fluids are obtained. The significant factor of Bingham properties, ？？ and ？？ values, of all ER fluid in the flow mode appeared to be greater than that in the shear mode, exclusive of soluble-arabic gum based ER fluid. Therefore, the Bingham model applied to the application of flow-mode type of device, the results obtained from the flow-mode type of experiment should be used.