Optimized Air Distribution for Contaminant Control in a Cleanroom: A Numerical Study

¹ Technical University of Denmark, International Centre for Indoor Environment and Energy, Department of Environmental and Resource Engineering, Kgs. Lyngby, Denmark
² Silesian University of Technology, Department of Heating, Ventilation and Dust Removal Technology, Gliwice, Poland

^* Corresponding author: mbiv@dtu.dk

Abstract

This study aimed to investigate the possibilities of providing the required cleanliness level in an ISO7/8 pharmaceutical cleanroom at a low air change rate of 10 ACH by optimizing the room airflow distribution. The research utilizes numerical modelling to examine the airflow pattern and particle removal effectiveness in a polluted full-scale cleanroom. A novel ventilation approach referred to as hybrid ventilation, which combined a non-unidirectional and a unidirectional supply diffuser, was used to control the particle concentration at reduced ACH. A comparison was made against the traditional mixing air distribution method that employs non-unidirectional supply diffusers. The study provides a qualitative and quantitative analysis of the relationship between room air distribution and particle dispersion. The results demonstrate that the new hybrid ventilation method effectively meets more stringent cleanliness requirements, even at 10 ACH, compared to the mixing air distribution at 20 ACH. The study also emphasizes the limited impact of increasing the ACH on improving the cleanroom cleanliness level. This study contributes to the field by providing a potential energy-saving strategy for pharmaceutical cleanrooms without compromising cleanliness requirements.