Validation and assessment of the CFD-0 module of CONTAM software for airborne contaminant transport simulation in laboratory and hospital applications

Abstract

Hospital and laboratory buildings are designed with intrinsic features for infection control, and are related to an intensive energy use. Although many studies suggest that insufficient ventilation increases the risk of disease transmission in the indoor environment, significant questions still remain on the ventilation requirements for airborne infection control. ASHRAE proposes high research priority on the study of indoor flow regimes, room pressurization and filtration, for hospitals and laboratories where infectious diseases agents are handled. The objective of this paper is to promote an assessment and validation of the CFD-0 module of the CONTAM software, for the simulation of airborne contaminant transport in hospital and laboratory applications. These objectives are justified by the fact that this public domain code, supported by the NIST, may be an important tool for studying the role of ventilation parameters in infection control for hospital and laboratory settings. Three benchmarks were selected for that task: the ASHRAE-RP 1271, geared to challenge the code ability in simulating the complex indoor airflow features, such as jets, separation, impingement, and thermal plumes, that arise in room transitional non-isothermal confined flow; A benchmark that resembles real laboratory spaces; and a third benchmark, that resembles real hospital isolation rooms. Results demonstrated that CFD-0 provided, at least, a marginally acceptable performance, for mixed and displacement ventilation modes. The prediction results are more meaningful than those using the “perfect mixture” assumption, for assessments on ventilation performance and personnel exposure to hazardous substances in these spaces.