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

Abstract

The entropy generation from convective hybrid nanofluid flow within the odd-shaped geometries using the finite element method is examined is examined. The flow domain is filled by variable porosity and permeability porous media. Also, the thermal conductivity is assumed to be heterogeneous, and the Brinkman extended non-Darcy model is applied to simulate the 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 a porous (case 3) and the entire domain is a non-porous (case 4). Different designs of the odd-geometry are taken into account based on the aspect ratio. The characteristic-based split (CBS) based on semi-implicit (SI) scheme is used to treat the governing equations. Simulations are carried out for various values of the maximum Darcy parameter $${\text{Da}}_{\hbox{max} }$$ , alumina-copper volume fraction $$\phi_{Al} , \phi_{Cu}$$ and different conditions of the porous domain. It is noted that the case of the heterogeneous thermal conductivity maximizes the irreversibility from heat transfer and total entropy generation. Also, a weakness in values of the average Bejan number is obtained as the Rayleigh number is grown, regardless the porous conditions.