Hovering of a rigid pyramid in an oscillatory airflow

Annie Weathers, Brendan Folie, Bin Liu, Stephen Childress, Jun Zhang

Research output: Contribution to journalArticle

Abstract

We investigate the dynamics of rigid bodies (hollow pyramids) placed within a background airflow, oscillating with zero mean. The asymmetry of the body introduces a net upward force. We find that when the amplitude of the airflow is above a threshold, the net lift exceeds the weight and the object starts to hover. Our results show that the objects hover at far smaller air amplitudes than would be required by a quasi-steady theory, although this theory accounts qualitatively for the behaviour of the system as the body mass becomes small.

Original languageEnglish (US)
Pages (from-to)415-425
Number of pages11
JournalJournal of Fluid Mechanics
Volume650
DOIs
StatePublished - May 10 2010

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hovering
pyramids
lifts
rigid structures
Air
hollow
asymmetry
thresholds
air

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Condensed Matter Physics

Cite this

Weathers, A., Folie, B., Liu, B., Childress, S., & Zhang, J. (2010). Hovering of a rigid pyramid in an oscillatory airflow. Journal of Fluid Mechanics, 650, 415-425. https://doi.org/10.1017/S0022112010000583

Hovering of a rigid pyramid in an oscillatory airflow. / Weathers, Annie; Folie, Brendan; Liu, Bin; Childress, Stephen; Zhang, Jun.

In: Journal of Fluid Mechanics, Vol. 650, 10.05.2010, p. 415-425.

Research output: Contribution to journalArticle

Weathers, A, Folie, B, Liu, B, Childress, S & Zhang, J 2010, 'Hovering of a rigid pyramid in an oscillatory airflow', Journal of Fluid Mechanics, vol. 650, pp. 415-425. https://doi.org/10.1017/S0022112010000583
Weathers, Annie ; Folie, Brendan ; Liu, Bin ; Childress, Stephen ; Zhang, Jun. / Hovering of a rigid pyramid in an oscillatory airflow. In: Journal of Fluid Mechanics. 2010 ; Vol. 650. pp. 415-425.
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