Qualitative analysis of natural ventilation: comparison between experimental tests on the water table and computational simulations in CFD

The optimization of natural ventilation in buildings contributes to the reduction of energy consumption. However, to precisely analyze the physical parameters involving natural ventilation, the use of complex software is required. Nevertheless, to address this limitation, the use of water tables is an accessible and easy-to-handle strategy that allows the visualization of the phenomenon, especially in the early stages of project. Therefore, the objective is to avaluate qualitatively assess whether the results generated on the water table accurately represent the natural ventilation flow in physical models. For this purpose, simplified physical experiments are compared with Computational Fluid Dynamics (CFD) simulations. The methodology consists of four stages: 1) Determination of the model; 2) Characterization of the water table and its input parameters for experiment development; 3) Description of the configurations adopted in computational simulations; and 4) Analysis of the results. The results were satisfactory, and the qualitative assessment of natural ventilation through the comparison of the water table and CFD simulation tools demonstrated compatibility, with significant similarities in fluid flow characteristics in both the internal and external areas of the dwelling.