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arXiv · 1412.3513

Electric-field-induced turbulent energy cascade in an oil-in-oil emulsion

Atul Varshney·Mayur Sathe·Shankar Ghosh·Anand Yethiraj·S. Bhattacharya·J. B. Joshi
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Abstract

We observe electro-hydrodynamically driven turbulent flows at low Reynolds numbers in a two-fluid emulsion consisting of micron-scale droplets. In the presence of electric fields, the droplets produce interacting hydrodynamic flows which result in a dynamical organization at a spatial scale much larger than the size of the individual droplets. We characterize the dynamics associated with these structures by both video imaging and a simultaneous, in situ, measurement of the time variation of the bulk Reynolds stress with a rheometer. The results display scale invariance in the energy spectra in both space and time.

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Atul Varshney, Mayur Sathe, Shankar Ghosh, Anand Yethiraj, S. Bhattacharya, J. B. Joshi. 2014-12-11. Electric-field-induced turbulent energy cascade in an oil-in-oil emulsion. https://doi.org/10.1039/c5sm02316e

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