Impacts of the Variable Properties of a Porous Medium on the Entropy Analysis Within Odd‑Shaped Enclosures Filled by Hybrid Nanofluids

摘要

The entropy generation from convective hybrid nanofluid flow within the odd-shaped geometries using the finite elementmethod is examined is examined. The flow domain is filled by variable porosity and permeability porous media. Also, thethermal conductivity is assumed to be heterogeneous, and the Brinkman extended non-Darcy model is applied to simulatethe porous medium. The geometry is considered partially/fully filled by the porous medium and four cases are assumed,namely, only the horizontal channel is a porous (case 1), only the vertical channel is a porous (case 2), the entire domain is aporous (case 3) and the entire domain is a non-porous (case 4). Different designs of the odd-geometry are taken into accountbased on the aspect ratio. The characteristic-based split (CBS) based on semi-implicit (SI) scheme is used to treat the governingequations. Simulations are carried out for various values of the maximum Darcy parameter Da_(max) , alumina-coppervolume fraction Φ_(Al), Φ_(Cu) and different conditions of the porous domain. It is noted that the case of the heterogeneous thermalconductivity maximizes the irreversibility from heat transfer and total entropy generation. Also, a weakness in values of theaverage Bejan number is obtained as the Rayleigh number is grown, regardless the porous conditions.