Entropy Generation In an Unsteady MHD Channel Flow With Navier Slip and Asymmetric Convective Cooling

The combined effects of magnetic field, Navier slip and convective heating on the entropy generation in a flow of a viscous incompressible electrically conducting fluid between two infinite horizontal parallel plates under a constant pressure gradient have been examined. Both the lower and upper plates of the channel are subjected to asymmetric convective heat exchange with the ambient fluid. The governing non-linear governing partial differential equations are solved using the MATLAB PDE solver. The entropy generation number and the Bejan number are also obtained. The influences of the pertinent flow parameters on velocity, temperature, entropy generation and Bejan number are discussed graphically. It is observed that the plate surfaces act as a strong source of entropy generation and heat transfer irreversibility. Also, the entropy generation number decreases for increasing values of the magnetic parameter. The slip parameters are found to control the entropy generation. By using asymmetric cooling of the plates, it is possible to operate the system with reduced entropy generation rate.