Comments on “Viscosity of high crystal content melts: dependence on solid fraction”

where η is the relative viscosity, φ the volume fraction of particles, B the Einstein coefficient (with a theoretical value B = 2.5), and α, β, γ are three adjustable parameters. The proposed parameterisation approximately reduces to the classical, well established relationships for small fractions. On the other hand, a weak point of equation (1) is that for large φ, the relative viscosity tends quickly to a constant value, because the non-linear term in the erf function rapidly saturates