Study of natural convection in thermosiphon constructed with two hyperbolic walls with the aid of the modified 'SIMPLER' code. Case for the walls maintained at constant and equal temperatures

The authors numerically study natural thermal laminar and bidimensional convection of a Newtonian fluid in the development of a thermosiphon in which the walls have hyperbolic surfaces, maintained at constant and equal temperatures. The transfer equations, written in original variables which are discretised in utilising the Patankar scheme of volume control, are resolved thanks to the double scanning method. The influence of the Grashof number, the form factor and of the half-height on the local and average Nusselt number, the output and the average output temperature, are analysed.