Electrorheological fluids: structures and mechanisms

摘要: Electrorheology denotes the control of a colloid's flow properties through an electric field. We delineate basic characteristics electrorheological (ER) fluids, and show that use effective dielectric constant concept can yield quantitative predictions. In particular, ground state structure, structural transition occurs under crossed magnetic fields, high-field stress its variation with particle size are all in good agreement experiments. The recently discovered giant effect, owing origin to molecular dipoles, is described contrasted conventional ER effect arises from induced polarization effects.