Work

Control of wind speed and contact angle on submicron particulate matter sampling

Year: 2025

Type: article

Abstract: While particulate matter (PM) instruments are widely used for air quality monitoring and policy development, there is limited research on how wind speed ( U 0 ) and contact angle ( θ ) affect the measurement accuracy of submicron PM, or particles with their diameters ≤ one µm (PM 1 ). This study addresses this gap by employing a wind tunnel experiment with a common sampling system featuring a customized thick-walled cylindrical metal inlet. The results reveal that wind-induced aerosol losses can reach up to 9%, and the sampling efficiency has a negative linear relationship with U 0 and a third-order polynomial relationship with cos( θ ). This model demonstrates a significant discrepancy with classic models in predicting sampling efficiency, which indicates the inapplicability of classic sampling efficiency models to submicron aerosols. The findings of this study can help correct wind-induced errors, improve sampling protocols, and develop new predictive models, which have implications for improving hazardous air quality warning systems and safeguarding public well-being.

Source: PeerJ

DOI: 10.7717/peerj.20235