University of Sistan and Baluchestan,
Iranian Society Of Mechanical EngineersChallenges in Nano and Micro Scale Science and Technology2821-000X1120130101Natural Convection and Entropy Generation in Γ-Shaped Enclosure Using Lattice Boltzmann Method11899110.7508/tpnms.2013.01.001ENE.FattahiFaculty of Mechanical Engineering, Babol University of Technology Babol, IranM.FarhadiFaculty of Mechanical Engineering, Babol University of Technology Babol, IranK.SedighiFaculty of Mechanical Engineering, Babol University of Technology Babol, IranJournal Article20130629This work presents a numerical analysis of entropy generation in Γ-Shaped enclosure that was submitted to the natural convection process using a simple thermal lattice Boltzmann method (TLBM) with the Boussinesq approximation. A 2D thermal lattice Boltzmann method with 9 velocities, D2Q9, is used to solve the thermal flow problem. The simulations are performed at a constant Prandtl number (Pr = 0.71) and Rayleigh numbers ranging from 10<sup>3</sup> to 10<sup>6</sup> at the macroscopic scale (Kn = 10<sup>-4</sup>). In every case, an appropriate value of the characteristic velocity is chosen using a simple model based on the kinetic theory. By considering the obtained dimensionless velocity and temperature values, the distributions of entropy generation due to heat transfer and fluid friction are determined. It is found that for an enclosure with high value of Rayleigh number (i.e., Ra=10<sup>5</sup>), the total entropy generation due to fluid friction and total Nu number increases with decreasing the aspect ratio.https://chal.usb.ac.ir/article_991_ed33fb88310481a59b7edd67542621f9.pdf