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Updated: Mar 28, 2026
08:58
Double Emulsion Generation Using a Polydimethylsiloxane PDMS Co-axial Flow Focus Device
Published on: December 25, 2015
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Multiscale flow in an electro-hydrodynamically driven oil-in-oil emulsion.
Atul Varshney1, Smita Gohil, Mayur Sathe
1Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel. atul.varshney@weizmann.ac.il.
Soft Matter
|December 24, 2015
Summary
This study reveals a new electro-hydrodynamic flow in viscous emulsions, creating large-scale structures and efficient mixing. The findings show scale-invariant energy spectra, similar to turbulent convection, in micro-scale systems.
Area of Science:
- Fluid dynamics
- Rheology
- Soft matter physics
Background:
- Efficient mixing in viscous fluids is challenging due to suppressed multi-scale flows.
- Highly viscous systems often hinder the generation of complex flow patterns necessary for effective mixing.
Purpose of the Study:
- To investigate a novel multi-scale flow driven by an external electric field in a highly viscous oil-in-oil emulsion.
- To characterize the dynamics and scale invariance of electro-hydrodynamic flows in micro-scale systems.
- To demonstrate the mixing efficiency achieved through these induced flows.
Main Methods:
- Utilized a highly viscous oil-in-oil emulsion with micron-size droplets.
- Applied an external electric field to induce electro-hydrodynamic flow.
- Measured bulk Reynolds stress using a rheometer.
- Performed micro-scale rheometric measurements via fiber cantilever fluctuation spectrum analysis.
Main Results:
- Observed dynamical organization at scales larger than individual droplets.
- Demonstrated scale invariance in energy spectra over three decades.
- Identified a power law in energy spectra similar to turbulent convection.
- Confirmed efficient mixing capabilities in the micro-scale system.
Conclusions:
- External electric fields can generate novel multi-scale flows in highly viscous emulsions.
- These electro-hydrodynamic flows exhibit scale-invariant properties analogous to turbulence.
- The study demonstrates a promising method for efficient mixing in micro-scale viscous systems.
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