A quasi-local measure of inter-scale transfer: An approach to understanding turbulence

M. K. Rivera; W. B. Daniel; S. Y. Chen; R. E. Ecke

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A quasi-local measure of inter-scale transfer: An approach to understanding turbulence

M. K. Rivera·W. B. Daniel·S. Y. Chen·R. E. Ecke

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Abstract

Many questions remain in turbulence research---and related fields---about the underlying physical processes that transfer scalar quantities, such as the kinetic energy, between different length scales. Measurement of an ensemble-averaged flux between scales has long been possible using a variety of techniques, but instantaneous, spatially-local realizations of the transfer have not. The ability to visualize scale-to-scale transfer as a field quantity is crucial for developing a clear picture of the physics underlying the transfer processes and the role played by flow structure. A general technique for obtaining these scale-to-scale transfer fields, called the filter approach, is described. The effects of different filters, finite system size, and limited resolution are explored for experimental and numerical data of two-dimensional turbulence.

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M. K. Rivera, W. B. Daniel, S. Y. Chen, R. E. Ecke. 2003-12-03. A quasi-local measure of inter-scale transfer: An approach to understanding turbulence. https://arxiv.org/abs/cond-mat/0312105

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