Date of Award
Master of Science
Department of Engineering Physics
Robert S. Wacker, PhD.
The impact of particle size and wind speed on brownout cloud development was investigated among various rotary aircraft using Continuum Dynamics, Inc. (CDI) Brownout Analysis Tool, a high physical fidelity brownout model that is used by both U.S. Army Aviation and NASA for Rotorwash analysis. Simulations were run over 125 different combinations of particle size, wind speed, and aircraft type then output data was post-processed to determine a transmissivity and ultimately a visibility value that could be used in developing a severity metric for the brownout clouds generated. For most aircraft types evaluated, stronger wind speeds and smaller particle diameters resulted in denser clouds. Wind speeds greater than 6 m s -1 were required to lift particles greater than 30 micrometers in diameter in most cases.
DTIC Accession Number
Swanson, Brandy A., "Investigating the Impacts of Particle Size and Wind Speed on Brownout" (2015). Theses and Dissertations. 93.