Mohammad Nemati - Ph.D. Student, Department of Mechanical Engineering, Yazd University, Yazd, Iran
Mohammad Saleh Barghi Jahromi - Ph.D. Student, Department of Mechanical Engineering, Yazd University, Yazd, Iran
Hajar Mohamadzade - Ph.D. Student, Department of Mechanical Engineering, University of Science and Technology, Tehran, Iran
Mohammad Sefid - professor, Department of Mechanical Engineering, Yazd University, Yazd, Iran

In this paper, the effect of shape and aspect ratio of wall on natural convection heat transfer of non-Newtonian fluid with power law model within two-dimensional enclosure in the presence of a uniform magnetic field by lattice Boltzmann method (LBM) is investigated. The left wall is at a constant hot temperature, while the right wall is kept on cold constant temperature and other walls are considered adiabatic. In this simulation, the flow field and temperature are calculated by simultaneously solving the flow and temperature distribution functions. The effect of various parameters such as Hartmann number, aspect ratio, different shape of the wall and power index of non-Newtonian fluid is investigated. The results show that increasing power index, aspect ratio and Hartmann number decrease the average Nusselt number. Also, the highest amount of heat transfer is generally associated with the case of a triangular wall. In addition, increasing the power index reduces the effect of the magnetic field.

LBM, Natural convection, Non-Newtonian fluid, Magnetic field, Different shape of the wall.