Entropy analysis and MHD mixed convection heat transfer of the magnetic nanofluid in an asymmetric T-shaped cavity using the lattice Boltzmann method

Abstract

The magneto hydrodynamic (MHD) mixed convection of titanium oxide/water nanofluids (NFs) in a T-shaped two-dimensional cavity is studied numerically in this article. The upper wall of the cavity has a low temperature and the lower walls of the cavity have a high temperature. The cavity has an inclination angle of 45⁰ under the influence of a horizontal magnetic field (MFD) with Ha = 20. On the upper wall, the slip parameter is changed from 0 to 0.1. The values ​​of entropy generation (ETG), Bejan number (Be), and Nusselt number (Nu), as well as velocity and temperature contours, are presented for different slip parameters when Richardson number (Ri) changes in the range of 0.1 to 100. Lattice Boltzmann method (LBM) is used for simulations. The results demonstrate that an enhancement of the slip parameter causes a decrease in the ETG and a reduction in Nu slightly. ETG and Nu have a decreasing trend by changing Ri from 0.1 to 10; but, they are increased with a further increase of Ri to 100. With an increase in Ri, the local Nusselt number on the left side of the cold wall decreases.