Using air curtain to control pollutant spreading for emergency management in a cleanroom

The present investigation aims to examine the pollutant dispersion flowfield in an IQC cleanroom. Experimentally, the airflow velocities were measured using a TSI 8495 hot-wire anemometer to inspect the flow characteristics. Three ppbRAE PGM-7240 photoionization detectors were employed to concurrently measure the spatial and temporal distributions of ethanol concentration from a gas-pollutant leaking source. The computational analysis was based on the time-dependent three-dimensional conservation equations of mass, momentum and species concentration for the incompressible isothermal turbulent flow with a k-ɛ two-equation turbulent model adopted for turbulence closure. Considering a massive amount of gaseous ethanol released from a malfunction machine, we presented a novel application of using an air curtain to resolve the personnel safety concern for emergency management in a contaminated cleanroom. For the cases without and with activation of an air curtain device, the airflow and contaminant characteristics were explored to better understand the pollutant spreading process for contamination control purpose. Numerical simulations were extended to verify if the air curtain device can establish a satisfactory shield for constraint of pollutant dispersal and optimize the sealing performance by systematically varying the parameters of ejection velocity, ejection angle and installation height.