Control strategy of fan filter units in cleanroom considering of the moving personnel

Abstract

Fan filter units (FFUs) are crucial to maintaining the cleanliness of cleanrooms. Traditionally, the air volume of FFU is not adjusted and maintained at a rated value, resulting in a huge amount of energy. Previous research proved that controlling FFUs based on personnel position was effective in cleanrooms with the non-uniform environment, and could further reduce the air volumes. However, the control strategy for moving personnel has not been given. In this study, moving personnel is numerically simulated in a typical cleanroom. A control strategy is proposed that only the 4 FFUs above the personnel operate at high velocity and still operate at high velocity for 10 seconds after the personnel leaves. The results show that the control strategy can guarantee satisfactory cleanliness, and the air volume of the proposed strategy can be reduced by 53.6% and 18.7% compared with the uniform velocity strategies at designed velocity and decreased velocity, respectively. Since fewer and fewer personnel are in the cleanroom, the study will conduce to tremendous energy reductions of FFUs, which may have promising application potential in cleanrooms