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Helicopter brownout – Can it be modelled?

Published online by Cambridge University Press:  27 January 2016

C. Phillips
Affiliation:
Department of Aerospace Engineering, University of Glasgow, Glasgow
H. W. Kim
Affiliation:
Department of Aerospace Engineering, University of Glasgow, Glasgow
R. E. Brown
Affiliation:
Department of Mechanical Engineering, University of Strathclyde, Glasgow

Abstract

Significant progress has been made to date in modelling, computationally, the formation and development of the dust cloud that forms in the air surrounding the rotorcraft under brownout conditions. Modern computational methods are able to replicate not only the development of the dust cloud in appropriate operational scenarios, but also the sensitivity of the shape and density of the dust cloud to the detailed design of the rotorcraft. Results so far suggest that attempts to ameliorate brownout by aerodynamic means, for instance by modifying the rotor properties, will be frustrated to some extent by the inherent instability of the flow field that is produced by the helicopter. Nonetheless, very recent advances in understanding the fundamental mechanisms that lead to the formation of the dust cloud may allow substantial progress to be made once certain elements of the basic physics of the problem are more fully understood and better quantified.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2011

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