A Comprehensive Validation of Two Airflow Models - COMIS and CONTAM

TLDR

Several airflow and contaminant dispersion models have been developed to study air distribution in buildings. The authors validated COMIS and CONTAM at three levels—inter‑program comparison with CBSAIR, AIRNET and BUS; controlled‑environment experiments (fan pressurisation, smoke and tracer‑gas tests) to assess envelope permeability, crack detection and inter‑zonal airflow; and field measurements in a residential building using tracer gas. The validation showed good agreement between COMIS and CONTAM and with other software, and between model predictions and measured data, though some discrepancies were noted.

Abstract

Abstract Several airflow and contaminant dispersion models have been developed to study air distribution in buildings. This paper reports the results of a comprehensive validation of two models: COMIS and CONTAM. The validation process was carried out at three different levels; inter-program comparison; validation with experimental data which was collected in a controlled environment; and finally, validation with field measurement data. At the inter-program level, the airflow rates and pressure values predicted by COMIS and CONTAM for a four-zone paper building were compared with the airflow rates and pressures predicted by CBSAIR, AIRNET and BUS. The results show good agreement between these software programs. The second level of validation compares the models' predictions with measured data collected in a controlled environment. Fan pressurisation, smoke and tracer gas tests were conducted to estimate the permeability of building envelope components, to locate cracks, and to determine the interzonal airflow rates between rooms. The results confirm that there is good agreement between predictions made by COMIS and CONTAM; there are, however, some differences between these models' predictions and the measured data. The predictions made by these models were also compared with the results of a tracer gas measurement carried out in a residential building. The predicted and measured values were in good agreement.