Investigating the Impacts of Particle Size and Wind Speed on Brownout

Abstract

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 delity brownout model that is used by both U.S. Army Aviation and NASA for Rotorwash analysis. Simulations were run over 125 di erent 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

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Document Details

Document Type
Technical Report
Publication Date
Mar 26, 2015
Accession Number
ADA614925

Entities

People

  • Brandy A. Swanson

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Biomedical

DTIC Thesaurus Topics

  • Air Force
  • Aircraft Equipment
  • Aircrafts
  • Airframes
  • Boundary Layer
  • Computational Fluid Dynamics
  • Fluid Dynamics
  • Fluid Flow
  • Geography
  • Governments
  • Optical Properties
  • Rotary Wing Aircraft
  • Surface Roughness
  • Turbulent Mixing
  • United States
  • United States Government
  • Weather Forecasting

Fields of Study

  • Environmental science

Readers

  • Aerosol Science/Aerosol Physics
  • Aerospace Engineering
  • Computational Modeling and Simulation