Numerical entropy analysis of MHD electro-osmotic flow of peristaltic movement in a nanofluid with a Darcy–Forchheimer porous medium

This study examines entropy generation in the magnetohydrodynamic (MHD) electro-osmotic peristaltic flow of a nanofluid through an asymmetric microchannel saturated with a Darcy–Forchheimer porous medium, including Hall current, Joule heating, temperature-dependent thermal conductivity, and velocity and thermal slip. The electric double-layer potential is obtained from the Debye–Hückel-linearized Poisson–Boltzmann equation, and the lubrication-reduced momentum, energy, and nanoparticle-concentration equations are solved with the MATLAB bvp4c collocation solver, which is verified against an exact limiting solution and through mesh- and tolerance-independence tests. Increasing the Hartmann number from 1 to 3 lowers the peak axial velocity by approximately 34 %, whereas increasing the Darcy number from 0.05 to 0.5 raises it approximately fivefold and increases the channel-averaged entropy generation by 41–163 %. The Forchheimer drag alters the velocity by less than 6 % for Fr ≤2. Increasing the Joule heating parameter from 0 to 1 raises the peak temperature by 29–43 %. A variance-based (Sobol) sensitivity analysis shows that the Joule heating parameter dominates the peak temperature and the total entropy generation, the thermal Grashof and Darcy numbers dominate the volumetric flow rate, and Brownian diffusion controls the Bejan number. The results provide quantitative guidance for the design of electro-osmotic micropumps and biomedical microfluidic devices.