Numerical natural convection in a sector-shaped enclosure

The purpose of this paper is to compare the numerical laminar two-dimension al unsteady natural convection in a partial sector-shaped enclosure submitt ed respectively to a constant heat flux density q1 and a uniform temperatur e T1 on the inner cylindrical wall. The numerical model performed in this p aper is applied more particularly for high Grashof numbers, in order to poi nt out the advent and the development of pre-turbulent flows. Results of nu merical runs are presented. The mean Nusselt number on active walls is repr esented as a function of the Grashof number Gr and the aspect ratio F-r The results may be correlated very well with an expression of the form (Nu) ov er bar = k1 Gr(1)(k2), for technical calculations.