TURBULENT FORCED CONVECTIVE HEAT-TRANSFER IN THE ENTRANCE REGION OF A CONFINED JET

Forced convective heat transfer in the entrance region of a confined turbulent jet is studied numerically. The solution of the transport equations is based on a combination of an iterative, finite-volume computational procedure using primitive dependent variables and a two-equation turbulence closure model. The separated flow zone, which extends as far as three pipe diameters, is observed to be a site of high turbulence. The heat transfer results show little sensitivity to the total number of grid points. The variation of the Nusselt number is influenced by the growth of the thermal boundary layer and the presence of the separated zone. Locations of the minimum and maximum Nusselt numbers are found to be functions of the Craya-Curtet number. Finally, the heat transfer predictions are clearly shown to be sensitive to the location of the grid point next to the wall.