Numerical simulation by a lattice Boltzmann method of fluid flow and heat transfer characteristics in a discreetly heated cavity containing water near its density maximum

Abstract

A partially heated square cavity containing water near its density maximum is studied numerically by a lattice Boltzmann method. This paper investigates the effect of varying the size of the heated portion [Formula: see text] as well as the imposed temperatures [Formula: see text] at the hot wall, which is modelized through the inversion parameter [Formula: see text]. Two thermal behaviors have been distinguished and discussed in light of the Nusselt number Nu computed at the cold wall [Formula: see text] and heatlines visualization: At [Formula: see text], a unicellular structure obtained for [Formula: see text] corresponding to [Formula: see text] leads to maximum heat transfer. At [Formula: see text], the maximum heat transfer is given by the bicellular structure obtained for [Formula: see text] corresponding to [Formula: see text]. From the results of this work, it can be concluded that in certain cases, [Formula: see text], the system reaches a maximum heat transfer at a low applied temperature [Formula: see text].