TY - JOUR T1 - Lattice Boltzmann Simulation of Magnetic Field Effect on Natural Convection of Power-Law Nanofluids in Rectangular Enclosures AU - Wang , Lei AU - Chai , Zhenhua AU - Shi , Baochang JO - Advances in Applied Mathematics and Mechanics VL - 5 SP - 1094 EP - 1110 PY - 2018 DA - 2018/05 SN - 9 DO - http://doi.org/10.4208/aamm.OA-2016-0066 UR - https://global-sci.org/intro/article_detail/aamm/12191.html KW - magnetic field, nanofluid, power-law viscosity, lattice Boltzmann method. AB -

In this paper, the magnetic field effects on natural convection of power-law nanofluids in rectangular enclosures are investigated numerically with the lattice Boltzmann method. The fluid in the cavity is a water-based nanofluid containing Cu nanoparticles and the investigations are carried out for different governing parameters including Hartmann number (0.0≤$Ha$≤20.0), Rayleigh number (104≤$Ra$≤106 ), power-law index (0.5≤$n$≤1.0), nanopartical volume fraction (0.0≤$ϕ$≤0.1) and aspect ratio (0.125≤$AR$≤8.0). The results reveal that the flow oscillations can be suppressed effectively by imposing an external magnetic field and the augmentation of Hartmann number and power-law index generally decreases the heat transfer rate. Additionally, it is observed that the average Nusselt number is increased with the increase of Rayleigh number and nanoparticle volume fraction. Moreover, the present results also indicate that there is a critical value for aspect ratio at which the impact on heat transfer is the most pronounced.