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Rotor wake interactions with an obstacle on the ground

Published online by Cambridge University Press:  06 March 2018

D.J. Pickles ,
R.B Green  and
M. Giuni
D.J. Pickles*
Affiliation:
Aerospace Science Division, School of Engineering, University Of Glasgow, Glasgow, United Kingdom
R.B Green
Affiliation:
Aerospace Science Division, School of Engineering, University Of Glasgow, Glasgow, United Kingdom
M. Giuni
Affiliation:
Aerospace Science Division, School of Engineering, University Of Glasgow, Glasgow, United Kingdom
*
[email protected]
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Abstract

An investigation of the flow around an obstacle positioned within the wake of a rotor is described. A flow visualisation survey was performed using a smoke wand and particle image velocimetry, and surface pressure measurements on the obstacle were taken. The flow patterns were strongly dependent upon the rotor height above the ground and obstacle, and the relative position of the obstacle and rotor axis. High positive and suction pressures were measured on the obstacle surfaces, and these were unsteady in response to the passage of the vortex driven rotor wake over the surfaces. Integrated surface forces are of the order of the rotor thrust, and unsteady pressure information shows local unsteady loading of the same order as the mean loading. Rotor blade-tip vortex trajectories are responsible for the generation of these forces.

Keywords

Helicopterground effectrotor wakevortex interaction
Type
Research Article
Information
The Aeronautical Journal , Volume 122 , Issue 1251 , May 2018 , pp. 798 - 820
Copyright
Copyright © Royal Aeronautical Society 2018 

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