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Flow Visualization Techniques for the Evaluation of Non-Contact Trace Contraband Detectors



Matthew E. Staymates, Wayne Smith, John G. Gillen, Richard T. Lareau, Robert A. Fletcher


Efforts are underway in the Surface and Microanalysis Science Division at the National Institute of Standards and Technology to study trace aerodynamic sampling of explosive particles using walk-through portal-based detection systems. Explosive trace detection portals are designed to screen human subjects for contraband particles and vapors. A human subject walks into a confining space where they are interrogated by a series of pulsed air jets and are screened for explosive materials by a chemical analyzer. The screening process requires particle and vapor removal, transport, collection, desorption, and detection. Aerodynamic sampling is the critical front-end process for effective detection. In this paper, various visualization techniques are employed to study portal-based aerodynamic sampling in detail. Particle lift-off and removal is visualized using high-speed videography, transport of air and particles by laser light scattering, and desorption surface heating and cooling patterns by infrared thermography. These tools are used to identify sampling inefficiencies and may be employed to study air and sea cargo screening and other methods of aerodynamic sampling of particles.
Proceedings Title
Forum on Fluid Measurement and Instrumentations
Conference Dates
August 2-5, 2010
Conference Location
Montreal, CO
Conference Title
ASME Fluids Engineering Division Summer Meeting 2010


particle sampling, trace sampling, aerodynamic sampling, explosive trace detector, trace detection portal, fluid flow visualization


Staymates, M. , Smith, W. , Gillen, J. , Lareau, R. and Fletcher, R. (2010), Flow Visualization Techniques for the Evaluation of Non-Contact Trace Contraband Detectors, Forum on Fluid Measurement and Instrumentations, Montreal, CO (Accessed June 25, 2024)


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Created August 1, 2010, Updated February 19, 2017