Evaluating Oxygen Deficiency and Toxic Gas Hazards Using CFD Modeling
Daniel Hall & Steve Trammell
Analysis and development labs as well as test and assembly areas often use a variety of inert, toxic and/or flammable gases in their operations. Usage of these gases are typically small volumes and general laboratory room ventilation systems are adequate to dilute any gases in process use to very low and safe levels. However, to address rare events such as pipe breaks or equipment failures which may release large quantities of gas, it is common to equip the labs with gas and O2 detection equipment to provide a warning to personnel. Placement of detection equipment is usually done by observation, convenience, or perceived effectiveness, such as near a power source, near an exit door, or near the equipment using the gas of concern.
This method of placement does not comprehend relative location of the leak to the detector, room air circulation or ventilation. This presentation will introduce the use of computational fluid dynamics (CFD) to this situation, which can model such leak scenarios and accurately predict room O2 or hazardous gas concentration over time, considering leak location, room geometry and room air supply and exhaust. An example using a typical laboratory layout and leak scenario will be presented and CFD modeling results presented.