Novel analysis of yield stress for giant electrorheological fluids

초록

We examine the universality of yield stress (ty(E0)) for giant electrorheological (GER) fluids both experimentally and theoretically. We found that published experimental data on yield stress of GER fluids for different materials and measurement conditions obey a universal yield stress scaling function. In other words, GER yield stress data in the literature collapse to a universal correlation: t = 1.313E tanhE using the scaled variables t = ty(E0) /ty(Ec) and E = E0/Ec. Here, Ec is the critical electric field strength. This novel universal correlation in hyperbolic tangent form differs from our previously published modified Bessel function form. Here, we decompose the GER system into a finite number of elementary regions filled with glueons A & B. In the limit where the elementary region size is reduced to zero, using a diffusion-reaction model for the binary system, a universal correlation was obtained. In modelling the reaction term, we assumed that electric field converts glueons A (active) into B (inactive), i.e., number of glueons B increases as the electric field strength increases. To fit experimental data, we assumed that the reaction term is quadratic in E0 for GER systems in contrast to linear in E0 for an ER system.

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