Electroosmotic and pressure-driven slip flow of fractional viscoelastic fluids in microchannels

This study investigates the unsteady electroosmotic slip flow of viscoelastic fluid through a parallel plate microchannel under the combined effect of electroosmotic and pressure gradient forcings. Analytical solutions for velocity and potential distributions are derived using the Debye-Hackel linearization, Laplace transform, and residue theorem. Numerical solutions are also provided based on the finite difference method. The process through which the velocity and flow rate attain a steady state is related to the governing groups, including the fractional calculus parameter alpha, slip coefficient L , Deborah number De , normalized electrokinetic width K and ratio 17 of the pressure to electroosmotic driving forces. Results show that an increase in alpha, De , L or 17 increases the time required to reach a steady state. The steady flow rate depends on L and K but is independent of alpha and De . For the same slip coefficient, increases in alpha, De or K increase the slip velocity at the wall. (c) 2022 Elsevier Inc. All rights reserved.