EXPERIMENTAL INVESTIGATION INTO THE ELECTRICAL MODELING OF ELECTRORHEOLOGICAL FLUIDS IN THE SHEAR MADE

An understanding of the mechanical, thermal and electrical response ch aracteristics of electrorheological (ER) fluids is vital to the design of any machine based on them. If the full potential of this original mechatronic medium is to be utilised, all will be included in steady a nd time domain-interactive optimisations of the particular application /process aim. The paper deals with the electrical modelling of ER flui ds in the shear mode and presents the results of experimental tests co nducted under true engineering conditions. In particular, the effects of the electrode separation and surface area are investigated for a ra nge of shear rates and field magnitudes and a study of the effect of f luid temperature is reported. It is shown that controller capacitance typically does not vary significantly with the field strength, the she ar rate or the temperature applied, but increases with increasing elec trode surface area and reduces with increasing interelectrode spacing. The electrical resistance of a controller, however,,although showing no reliable dependency on shear rate, reduces with increasing field st rength, temperature and electrode surface area and increases with incr easing interelectrode gap.