Thermo-hydraulic characteristics investigation of nanofluid heat transfer in a microchannel with super hydrophobic surfaces under non-uniform magnetic field using Incompressible Preconditioned Lattice Boltzmann Method (IPLBM)

Present study concerns the heat transfer and fluid flow investigation of thermo-hydraulic characteristics of a nanofluid in a microchannel with super hydrophobic surfaces. In this regard, the walls of microchannel are kept in constant temperature. The incompressible version of lattice Boltzmann method with precondition factor (IPLBM) is employed to achieve a true prediction of friction factor and Nusselt number under the effect of ascending magnetic field. Simulations are performed for volume fraction of nanoparticles, Ha number (Ha) and dimensionless slip coefficient of respectively 0% to 2%, 0 to 40 and 0 to 0.1. Results show that volume fraction and Hartman numbers cause increase in Nu number and friction factor, whereas dimensionless slip coefficient has various effects on Nu number; unlike friction coefficient that causes it to reduce. The results indicated that with tuning the hydrophobicity level, one can yield a specific behavior in microchannel, so that upon using super hydrophobic surface having a dimensionless slip coefficient 0.1, at Ha number of 40 concerning a nanofluid that is of 2% volume fraction, the shear stress reduces to approximately 70%. Also, in this condition Nu number only reduces 1.7%. Numerical procedure has been validated by comparing with experimental results as well as analytical and numerical ones.