Examples of how CFD may be used to demonstrate dynamic effects in laboratories.
Fume Hood Spill due to a Walk-By
Shown from a plan view, a person walks by one fully open and improperly loaded fume hood in a lab. Usually, this type of hood performs well over a wide range of operating conditions, but the combination of poor loading, a wide open sash and the currents from a moving person cause a momentary spill. The person is walking at 4 fps and the cloud surface has a concentration of 0.1 ppm SF6.
Fume Hood Spill due to a Rapid Sash Motion
Shown from an isometric view, a person fully opens the sash of a hood in less than one second. Because this is a variable air volume system, the controls, fan and air momentum take at least 3 seconds to adjust for the new sash opening. The sudden loss of air speed through the open sash causes a momentary spill that will disappear as the system compensates. In the mean time, contaminants will disperse into the breathing zone of the lab worker. Total length of animation is 2.8 seconds.