Improvement of the performance of a simple box model using CFD modeling to predict indoor air formaldehyde concentration

Abstract

The purpose of this study is to improve the predictive potential of a simple box model by using CFD simulation. In this easy-use box model, the material/air mass transfer is governed by a convective coefficient of pollutant through the boundary layer settling on the surface of material (hoi) which is a key parameter for the prediction of indoor air pollution. The aim of this study is to better assess this parameter as function of several variables (material surface emissions, room configurations and ventilation conditions) by means of CFD simulations. First, dimensional analysis method is applied to CFD results to establish a new relationship between physical parameters involved in the transfer of compounds in air, particularly room characteristic length, mean air velocity in inlet section area and molecular diffusion of formaldehyde in air. Thus, the validity of this relation is tested by CFD modeling for large range of room sizes, mean air velocities and inlet section locations. Lastly, results of a first measurement campaign show the improvement of the prediction of the box model compared to the previous version including this new relation by a better assessment of indoor material contributions to indoor air formaldehyde concentration.