Fundamental Study of Fluid Transfer using Electro-Rheological Effect

Experimental and theoretical examinations have been made on the method of feeding an Electro-Rheological-Fluid which effectively uses the electronic characteristics of the ERF whose apparent viscosity is changed by the application of voltage. The principle and configuration of this pump and the methods of theoretical analysis are described, and the influences of the voltage applied and the rotation speed on the feeding characteristics are examined. Experiments showed that even when the dispersoid-type ERF is used, not only the induced viscous stress but also the viscosity is affected by the electric field strength and that the induced viscous stress obtained under the consideration of variable viscosity becomes about an half of the value obtained by assuming that the viscosity is held constant irrespective of the application of the voltage. The analysis gave qualitative evaluations about the flow rate and pressure difference. The condition of pseudo-plastic fluid gives the result that the flow rates in pumps and annular pipes are in proportion to the square of the pressure difference, and this fact agrees well with the relationship obtained experimentally.