Innovative use of fluorescein for the air path study within light-weight wall assemblies

This technique was tested on a number of preliminary tests which showed consistent results and a good repeatability of the measurement. A fluorescein transport model was developed to facilitate the comparison between the experimental fluorescein concentration mappings and the numerical velocity fields. This method was then applied to a specific configuration: an air channel in contact with porous media. A simple analysis of the resulting fluorescein concentration mappings enabled to draw conclusions on the impact of parameters such as the flow velocity or the insulation material on the air infiltration. It has also given evidences of phenomena such as the appearance of thin air gaps between the components of the wall assembly. The results were compared to a numerical study with the fluorescein transport model coupled to a CFD model.