Effect of Wedge-Shaped Deflectors on Flow Fields of Dual-Stream Jets
نویسندگان
چکیده
The effect of wedge-shaped fan flow deflectors on the mean and turbulent flow-fields of dual-stream jets is investigated. Several wedge-shaped deflector concepts were used to create asymmetry in the plume of a dual-stream jet issuing from a scaled down version of the NASA Glenn ‘5BB’ bypass-ratio 8 turbofan nozzle. The deflector configurations comprised internal and external wedges with and without a pylon. Some external wedges incorporated local extensions of the fan nacelle. All the deflectors reduced radial velocity gradients, magnitudes of peak Reynolds stresses, and peak turbulent kinetic energy beneath the jet centerplane, with an increase above the jet centerplane. A correlation was obtained between the maximum radial velocity gradient and the peak turbulent kinetic energy in the dominant noise source region.
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