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Multi-zone Modeling of Size- Resolved Outdoor Ultrafine Particle Entry into a Test House



Dong H. Rim, Andrew K. Persily, Lance L. Wallace, William S. Dols, Steven J. Emmerich


Airborne particle transport into buildings is important for human exposure to particles and associated health effects. The present study investigated the entry of size-resolved outdoor ultrafine particles into a test building under three different ventilation scenarios using a multi-zone airflow and contaminant transport model. Measurement and simulation of the entry of outdoor ultrafine particles into a residential test building were performed and the results compared. These results show that simulations need to consider both particle deposition and penetration losses to predict accurately the time-varying particle concentrations in buildings. Both deposition and penetration have significant effects on the predictions for closed window condition, while deposition loss is much more important than penetration for open window conditions. With windows open, the filtering effect of the building shell decreases and more outdoor particles enter the building. The study results also show how the indoor–outdoor (I-O) concentration ratio varies with particle size and building operating conditions. The comparison between measurements and prediction suggests that multi-zone particle transport model can provide insight into the general trend of particle entry into buildings under various building operating scenarios.
Atmospheric Environment


ultrafine particles, indoor-outdoor relationship, multi-zone modeling


Rim, D. , Persily, A. , Wallace, L. , Dols, W. and Emmerich, S. (2012), Multi-zone Modeling of Size- Resolved Outdoor Ultrafine Particle Entry into a Test House, Atmospheric Environment, [online], (Accessed April 20, 2024)
Created December 11, 2012, Updated February 19, 2017