AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Particle Removal from Substrates with an Impinging Air Jet
BABAK NASR, Jana Kesavan, Andrea R. Ferro, Goodarz Ahmadi, Suresh Dhaniyala, Clarkson University
Abstract Number: 559 Working Group: Environmental Fate of Infectious Aerosols
Abstract Resuspension of chemical and biological particles from surfaces is a concern from a human health perspective. The net adhesive force acting on particles depends on particle and surface properties and the nature of the external force field. While several theoretical particle adhesion models exist, their implementation is made challenging by the uncertainties in the particle/surface properties and in calculating the external force fields. Here, we use a combination of computational fluid dynamics (CFD) simulations and experimental testing to validate the predictions of classical adhesion models. Particle removal from surfaces is possible when acted upon by flow with a velocity larger than a critical shear velocity. For removal of particles smaller than 10 µm, the critical shear velocities required are large, and one possible way to obtain these large shear velocities is by using jets directed at substrates. In this study, CFD simulations were conducted to determine the characteristics of flow exiting a nozzle and impinging on a substrate. The simulation results were analyzed to determine shear velocities along the surface and the calculated values were compared against theoretically-predicted critical values. The spatial extent of removal of particles of different sizes was then determined. The CFD-predicted removal regions for particles of different sizes were compared against experimental data obtained at ECBC for a range of particle sizes and relative humidities. The modeling details and experimental approach will be discussed in this presentation.