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Nonequilibrium fluctuation-induced Casimir pressures in liquid mixtures
T R Kirkpatrick1,2, J M Ortiz de Zárate3, J V Sengers1
1Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA.
Physical Review. E
|April 15, 2016
Summary
This study derives Casimir-like pressures from nonequilibrium concentration fluctuations in liquid mixtures, particularly those influenced by the Soret effect. These pressures are compared to those from temperature fluctuations in single-component fluids.
Area of Science:
- Thermodynamics
- Physical Chemistry
- Fluid Dynamics
Background:
- Nonequilibrium thermodynamics describes systems not in equilibrium.
- The Soret effect describes how temperature gradients induce concentration gradients in mixtures.
- Casimir effects typically arise from quantum fluctuations.
Purpose of the Study:
- To derive expressions for Casimir-like pressures in liquid mixtures due to nonequilibrium concentration fluctuations.
- To investigate the influence of the Soret effect on these pressures.
- To compare these pressures with those arising from temperature fluctuations.
Main Methods:
- Derivation of theoretical expressions for pressure.
- Application of Soret effect principles to liquid mixtures.
- Comparative analysis of fluctuation-induced pressures.
Main Results:
- Expressions for Casimir-like pressures induced by concentration fluctuations were derived.
- The Soret effect was shown to be a key factor in generating these pressures.
- A comparison highlighted differences between concentration and temperature fluctuation-induced pressures.
Conclusions:
- Nonequilibrium concentration fluctuations can induce Casimir-like pressures in liquid mixtures.
- The Soret effect plays a crucial role in this phenomenon.
- Experimental verification of these pressures is feasible and suggested.
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