A fractional-order Maxwell model for non-Newtonian fluids

This work considers an extension of the fractional-order Maxwell arrangement to incorporate a relaxation process with non-Newtonian viscosity behavior. The resulting model becomes a fractional-order nonlinear differential equation with stable solution converging asymptotically to a unique equilibrium point. Expressions for the corresponding storage and loss moduli as function of strain frequency and amplitude are computed via a first-harmonic analysis of the differential equation. Some distinctive features and their relationship to the classical and fractional-order linear Maxwell models are discussed. Three examples are used to illustrate the ability of the fractional-order Maxwell model to describe experimental data.