The simultaneous effects of image force and diffusion on ultrafine particle deposition onto vegetation: A wind tunnel study

Abstract

AbstractAtmospheric ultrafine particles (UFP) and their associated sources and sinks continue to attract significant research attention in climate and air pollution science. Vegetation is an important sink for UFP given its large area coverage. What remains a subject of inquiry are the aerodynamic and electromagnetic processes governing the aforementioned vegetation sink. Single fiber theory can explain deposition of zero charged UFP onto vegetation by treating vegetation as filter media. However, the ability of single fiber theory to predict deposition of charged UFP onto vegetation remains to be explored and frames the scope here. Wind tunnel experiments were used to investigate UFP dry deposition onto Juniper branches (Juniperus chinesis) under three different wind speeds (0.3, 0.6, and 0.9 m/s). Results indicate that the single fiber theory can describe the deposition of singly charged particles onto vegetation if both the image force and Brownian diffusion are simultaneously considered. The image for...