Comparison of network theory and mechanical dynamic model theory in a parallel duct ER fluid flow

摘要

We proposed a shear rheological relation based on a network theory regarding suspension-type electro-rheological fluid (ERF) having smectite particles. The theoretical constitutive equations concerning ERF under a D.C. electric field were derived using Rodge's network theory. The equations have creative and destructive functions representing behavior as aggregated particles influenced by shear flow and electric field. These numerical results of viscosity based on the equations were compared with experimental data regarding static shear stress in relation to shear rate obtained using a rotating concentric cylindrical rheometer. Our theory well explains the experimental data both quantitatively and qualitatively. The viscosity behaves as a non-affine motion at a small shear rate range and as an affine motion at large one. Next, the theoretical result was compared with that of the mechanical model having Maxwell model in a parallel duct ERF flow problem. The theoretical result of network theory can explain the experimental data of pressure difference at large given flow velocity. At small given flow velocity range, the mechanical model can explain the experimental data.