Publication Date:
1992-02-01
Description:
Incoherent turbulent motion modulated by coherent large-scale motion contributes to second-order coherent stresses. The spatial distribution of wave-induced stress was measured in a jet whose cross-section had been distorted through controlled resonant interactions between two forced, helical waves spinning in opposite directions. The transfer of energy from the coherent motion to broadband turbulence is documented. Shape assumptions are examined by comparing radial distributions to predictions from linear, inviscid stability theory. Control over small-scale mixing is examined by demodulating the coherent envelope of small-scale turbulence and by correlating it with features of the coherent, large-scale motion. Coherent production is shown to be associated with the roll-up process and there is evidence of secondary, inflexional instabilities. © 1992, Cambridge University Press. All rights reserved.
Print ISSN:
0022-1120
Electronic ISSN:
1469-7645
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
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