Effects of Helicity on Lagrangian and Eulerian Time Correlations in Turbulence
نویسندگان
چکیده
Taylor series expansions of turbulent time correlation functions are applied to show that helicity influences Eulerian time correlations more strongly than Lagrangian time correlations: to second order in time, the hclicity effect on Lagrangian time correlations vanishes, but the helicity cffect on Eulerian time correlations is nonzero. Fourier analysis shows that the hclicity effect on Eulerian time correlations is confined to the largest inertial range scales. Some implications for sound radiation by swirling flows arc discussed. Key words, hclicity, timc correlations Subject classification. Fluid Mechanics
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