Methodology for the Evaluation of Natural Ventilation in ... - Cham

Figure 39. Two Heated Zone ModelWith two heated zones, one above the other, both the effects due to radiation from the heaters ineach heated zone and any heat transfer between the zones due to conduction from the ceiling ofthe ground floor zone through the floor of the first floor zone had to be accounted for.Experiments were carried out with for two cases, one with the stacks open and one the stacksclosed. The window location was kept constant for these cases, with only a single set of lowerwindows in each heated zone was left open.A CFD model was created to compare the results of the experimental model with a numericalmodel. As with the single-heated zone case, the total heat input was equal to the combinedheater output. In the two-zone case, however, not only the radiation from floor to ceiling, butalso the heat transfer between the ground floor and first floor zones had to be accounted for inthe model. This modification was done in a similar manner to the way it was done in the singlezonecase. Plates were located on the ceiling to account for the radiation to the ceiling for eachzone, and a plate was added to the floor of the first floor zone with a low-level heat flux of 15Watts per square meter to account for the heat transfer from the ground floor zone to the firstfloor zone.110