Computational analysis of room pressure control in airtight cleanrooms

Room pressure differential is an important aspect in order to guarantee sufficient contamination control, but is difficult to control in airtight cleanrooms. This research uses simulation models to get an understanding and to quantify the room pressure controllability of airtight cleanrooms. The most influential parameters on the room pressure controllability are identified using a sensitivity analysis. The effects of the shell airtightness and overflow flowrates are quantified, and the effect of a flow/pressure cascade with three coupled rooms is investigated. Also, the effect of other parameters in the control system on the room pressure controllability are quantified. The main conclusion is that creating a flow/pressure cascade with a substantial flow rate can lead to significant improvements in room pressure controllability