Impact of the magnetic field and the height and number of triangular blades inside a rectangular cavity on natural convection heat transfer

Abstract

In this article, the effect of the blades placed in a cavity on the natural flow of alumina/water nanofluid is examined. The cavity has two insulated walls, a cold wall at the top, and a hot wall at the bottom affected by a magnetic field. The triangular blades at the same temperature at the bottom wall are placed on the wall. For the simulations, the Lattice Boltzmann Method (LBM) is used. The findings show that the average Nusselt number (Nu-Av) increases by more than 96 % when the dimensionless length of the blades (L-B) is raised from 0.3 to 0.7 for the case of 3 blades. With the initial increase in the L-Bs, the Nu is increased. The L-B of 0.4 and the highest value of the Nu-Av are equivalent. As the L-Bs is enhanced, the Nu is decreased. At Ra = 103, the enhancement in the number of blades (N-Bs) causes an increment in heat transfer (HTR), but at Ra = 105, maximum HTR occurs when the N-Bs is 2, and enhancing the N-Bs causes a decrease in HTR.