Turbulence management in free shear flows by control of coherent structures

The possibility of controlling turbulence by manipulating coherent structures is discussed. The processes of the generation, evolution, and interaction of coherent structures are described together with measurements necessary to analyze such coherent-structure properties as coherent vorticity, incoherent turbulence intensities, coherent and incoherent Reynolds stresses, and coherent turbulence production. Experimental findings are presented, in which the modified coherent structures were shown to result in favorable effects on the turbulence field.