Effect of uniform sinusoidal roughness on natural convection in an enclosure with partially linearly heater

The aim of the present study is to examine natural convection heat transfer in a square cavity filled with SWCNT-water nanofluid using lattice Boltzmann method. The left wall is smooth and partially heated linearly, while uniform sinusoidal roughness elements are placed on right wall and it is maintained at the constant temperature of Tc. The top and the bottom horizontal walls are smooth and insulated against heat and mass. The variation of density is slight; thus, hydrodynamics and thermal fields equations are coupled using the Boussinesq approximation. The density and energy distribution are both solved by D2Q9 model. The influence of pertinent parameters, such as Rayleigh number (Ra), solid volume fraction of nanoparticles (φ) and frequency of uniform sinusoidal roughness elements (N) on flow and heat transfer fields is investigated in the present paper. Results show that the heat transfer increases with the increment of Rayleigh number and nanoparticles volume fraction. It is observed that for a fixed Rayleigh number, by tuning the of roughness elements, maximum average Nusselt number occurs for N=8, but the minimum value of Nusselt number is function of Rayleigh number

کلیدواژه ها:

Natural convection ، sinusoidal roughness ، nanofluid ، lattice Boltzmann method ، D2Q9 Model