A study on mixed electro-osmotic/pressure-driven microchannel flows of a generalised Phan-Thien–Tanner fluid

This work presents new semi-analytical solutions for the combined fully developed electro-osmotic pressure-driven flow in microchannels of viscoelastic fluids, described by generalised Phan-Thien–Tanner model (gPTT) recently proposed Ferrás et al. (Journal Non-Newtonian Fluid Mechanics, 269:88–99, 2019). version PTT a function trace stress tensor—the Mittag–Leffler function—where one or two fitting constants are considered order to obtain additional flexibility. The solution is obtained under sufficiently weak electric potential that allows Debye–Hückel approximation electrokinetic fields and thin double layers. Based on solution, effects various relevant dimensionless numbers assessed discussed, such as influence $$\varepsilon Wi^2$$ , parameters $$\alpha $$ $$\beta gPTT model, also $${\bar{\kappa }}$$ parameter. We conclude characteristics enhance both velocity distribution across microchannels. high zeta finite size ions studied numerically.