Thermokinetic transport of dilatant/pseudoplastic fluids in a hydrophobic patterned micro-slit

The flow enhancement and convective heat transfer along with entropy generation analysis are studied numerically in a micro-slit with alternating hydrodynamic slip patches. The advances in molecular simulations and micro-scale experiments confirmed that the slip of fluid on the solid surfaces occurred at small scale flows and the traditional no-slip boundary conditions cannot be applicable for the flow simulation at the micro- and nano-scale. The coupled Poisson-Boltzmann-Navier-Stokes equations dealing with an external electric potential are involved for the flow enhancement and entropy generation analysis of non-Newtonian fluids in a micro-slit with periodic slips. From the finite volume simulation, it is observed that the drag force effect is very strong along the wall for the transportation and mixing of fluids. This effect is found to be minimized by imposing periodic hydrophobic slippage along the boundary. An additional pressure gradient is generated by imposing electrokinetic pumping, resulting in a higher velocity gradient in the flow direction in the presence of viscous dissipation and Joule heating effects. The results are predicted in terms of the flow enhancement factor (E-f) (which provides maximum species transport), the average heat transfer rate (Nu), and the average entropy generation due to fluid friction, heat transfer, and Joule heating effects. The advantages and disadvantages of utilizing slip conditions are discussed, which has large scale applications on drug delivery and DNA analysis and sequencing, since cell damage due to pumping will be minimized.