On the natural displacement ventilation flow through a full scale enclosure, driven by a source of buoyancy at floor level

This paper presents experimental data for the temperature stratification established within a full-scale enclosure, for the natural displacement ventilation flow driven by a source of buoyancy at floor level within the space with air as the working fluid. A range of predictive techniques is also investigated for the flow, and for each technique a critical comparison with the experimental data is presented. It is confirmed that the salt-bath modelling technique and related mathematical model of Linden et, al. (1990) is not appropriate for the prediction of this type of ventilation flow in full-scale buildings. Computational fluid dynamics is a powerful technique that can yield realistic predictions for this type of ventilation flow. Even this approach, however, requires further investigation before it can be used routinely. In particular, this paper illustrates the effect of applying different models of turbulence, and highlights the requirement to employ a complete thermal   radiation   model   when   using   the   CFD technique to predict this class of flow.