Purpose – This paper aims to investigate the entropy generation due to magnetohydrodynamic natural
convection flow and heat transfer in a porous enclosure filled with Cu-water nanofluid in the presence of
viscous dissipation effect. The left and right walls of the cavity are thermally insulated. There are heated and
cold parts, and these are placed on the bottom and top wall, respectively, whereas the remaining parts are
thermally insulated.
Design/methodology/approach – The finite volume method is used to solve the dimensionless partial
differential equations governing the problem. A comparison with previously published woks is presented and
is found to be in an excellent agreement.
Findings – The minimization of entropy generation and local heat transfer according to different values of
the governing parameters are presented in details. It is found that the presence of magnetic field has negative
effects on the local entropy generation because of heat transfer and the local total entropy generation. Also, the
increase in the heated part length leads to a decrease in the local Nusselt number.
Originality/value – This problem is original, as it has not been considered previously.