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Abstract

An experimental investigation was conducted to characterise the gust environment generated by a cascade of sinusoidally oscillating vanes in the Cranfield University 1.52 m by 1.14 m low-speed, open-jet, closed-circuit wind tunnel operating at 7.5 ms⁻¹ and 14.5 ms⁻¹. Measurements were made at four stream-wise and three vertical positions in the flow-field downstream of the vanes using a cross-wire anemometer. The oscillation angle of the vanes was set at ±8° and ±12° with frequencies of 0.5 Hz, 1.0 Hz and 2.0 Hz corresponding to a reduced frequency of between 0.01 and 0.07. The vertical components of velocity and turbulence intensity were shown to be consistent for the range of measurement points chosen. The peak vertical velocity component downstream of the vanes was shown to be proportional to the maximum vane angle of attack but largely independent of reduced frequency.

Keywords

Gust generator oscillating aerofoil

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The characterisation of a gust generator for aerodynamic testing

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