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Updated: May 25, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
Quantifying mixing in viscously unstable porous media flows
Birendra Jha1, Luis Cueto-Felgueroso, Ruben Juanes
1Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 48, Cambridge, Massachusetts 02139, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2012
Summary
Viscous fingering, a fluid instability, enhances mixing by creating disorder. Our study introduces a new model for this mixing process, highlighting the role of mechanical dissipation.
Area of Science:
- Fluid Dynamics
- Hydrodynamic Instabilities
- Mixing Processes
Background:
- Viscous fingering occurs when a less viscous fluid displaces a more viscous fluid.
- This instability is crucial for mixing in miscible fluids, affecting the velocity field and mixing rate.
Purpose of the Study:
- To analyze the mixing process signature in viscously unstable flows.
- To develop a reduced-order model for mixing in these flows.
Main Methods:
- High-resolution numerical simulations were employed.
- A computational strategy stable for arbitrary viscosity ratios was used.
Main Results:
- The study analyzed the characteristic mixing signature in viscously unstable flows.
- A reduced-order model was proposed, incorporating mechanical dissipation rate.
Conclusions:
- The proposed model captures the interplay between channeling and interfacial area creation due to viscous fingering.
- This work offers a new perspective on modeling mixing in such systems.
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