Indoor-outdoor pollutant transport through a hollow cube with a cross-ventilating flow

Cross-ventilation plays a critical role in dispersing indoor pollutants by promoting the exchange of indoor and outdoor air. To investigate pollutant transport in such scenarios, we experimentally investigate the flow through a hollow cube immersed in an atmospheric boundary layer as an idealized representation, with a ground-level passive scalar (pollutant) source placed at the centre of the building. The focus is on characterizing the velocity and concentration fields to understand the scalar transport mechanisms within and outside the cube. Two different experiments are conducted comparing results from the University of Surrey EnFlo wind tunnel and the University of Southampton water tunnel. The wind tunnel experiments used a laser Doppler anemometer (LDA) and a Fast flame ionization detector (FFID) to collect point measurements of the velocity and concentration, respectively. The water tunnel experiments used Planar Laser-Induced Fluorescence (PLIF) and Particle Image Velocimetry (PIV) to obtain simultaneous measurements of scalar and flow fields. The insights gained from this study can potentially improve our understanding and help model pollutant exchange between indoor and outdoor environments, especially in complex atmospheric boundary layer conditions