Performance assessment and optimization of air curtain for pollutant containment around a semi-open industrial building: A predictive response surface model

Vehicle unloading in semi-open industrial buildings frequently release fugitive pollutants, creating significant environmental exposure risks. Current studies have mainly focused on pollutant containment by local exhaust ventilation, while a comprehensive multi-parameter assessment for air curtain performance in semi-open industrial buildings remain undeveloped. This study aims to systematically investigate and optimize the controlling performance of an air curtain for this issue using computational fluid dynamics (CFD) and response surface methodology (RSM). To validate CFD results, simulated results are compared with wind tunnel experimental results. Meanwhile, 51 test cases are conducted to comprehensively explore the interplay among the bottom opening ratio, natural wind direction, and air curtain’s key parameters (jet velocity, angle, and installation type). Results reveal that bottom opening ratio significantly affects pollutant escape, revealing the 30% ratio representing the worst-case scenario. The control efficiency is also sensitive to different natural wind directions. Furthermore, a predictive model with errors under 5% is proposed by RSM, achieving an R² value of 0.96. This model successfully predicts control efficiency for various parameter combinations and provides the optimal operational parameters for three installation types of the air curtain, predicting a peak control efficiency of 98.33% with a top installation at a dimensionless jet velocity of 3.50 and a jet angle of 4.03°. This work provides a theoretical reference for the practical design and operation of air curtains.