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The flow around a model helicopter main rotor in ground effect

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Abstract

Wind tunnel measurements of the wake below and ahead of a model helicopter main rotor in simulated forward flight in ground effect are presented. The wind tunnel used was equipped with a rolling road, and the ground speed was matched to the wind tunnel speed for a representative simulation in the wind tunnel of forward flight over the ground. Particle image velocimetry was used to investigate the structure of the wake, and it was observed that the moving ground had a remarkable effect on the flow; the wake is closer to the rotor and its size is reduced compared with the stationary ground case. The detailed distribution of vorticity within the wake is affected by the moving ground, and the mechanism for this is discussed in the paper.

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Acknowledgments

N. D. Nathan was in receipt of a British Council Overseas Research Student award. The authors wish to thank the technical staff of the School of Engineering, University of Glasgow, for assistance in setting up the rotor rig. The PIV system was funded under the Glasgow Research Partnership in Engineering scheme. Elements of this work formed a contribution to GARTEUR Action Group HC-AG17.

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Authors and Affiliations

  1. Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore

    N. D. Nathan

  2. Aerospace Sciences Division, School of Engineering, University of Glasgow, Glasgow, Scotland, UK

    R. B. Green

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  1. N. D. Nathan
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  2. R. B. Green
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Correspondence to R. B. Green.

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Nathan, N.D., Green, R.B. The flow around a model helicopter main rotor in ground effect. Exp Fluids 52, 151–166 (2012). https://doi.org/10.1007/s00348-011-1212-1

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  • DOI: https://doi.org/10.1007/s00348-011-1212-1

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