# Non-equilibrium concentration fluctuations in binary liquids with realistic boundary conditions

@article{OrtizdeZrate2015NonequilibriumCF, title={Non-equilibrium concentration fluctuations in binary liquids with realistic boundary conditions}, author={Jos{\'e} Marıa Ortiz de Z{\'a}rate and T. R. Kirkpatrick and Jan V. Sengers}, journal={The European Physical Journal E}, year={2015}, volume={38}, pages={1-9} }

Because of the spatially long-ranged nature of spontaneous fluctuations in thermal non-equilibrium systems, they are affected by boundary conditions for the fluctuating hydrodynamic variables. In this paper we consider a liquid mixture between two rigid and impervious plates with a stationary concentration gradient resulting from a temperature gradient through the Soret effect. For liquid mixtures with large Lewis and Schmidt numbers, we are able to obtain explicit analytical expressions for…

## 19 Citations

### The NEUF-DIX space project - Non-EquilibriUm Fluctuations during DIffusion in compleX liquids

- PhysicsThe European physical journal. E, Soft matter
- 2016

The focus of the project is on the investigation in micro-gravity conditions of the non-equilibrium fluctuations in complex liquids, trying to tackle several challenging problems that emerged during the latest years, such as the theoretical predictions of Casimir-like forces induced by non-Equilibrium fluctuations.

### Non-local fluctuation phenomena in liquids

- PhysicsThe European physical journal. E, Soft matter
- 2016

The experimental evidence for the consistency between this assumption of local equilibrium in the equations and the non-local fluctuation phenomena observed is reviewed.

### Kinetics of growth of non-equilibrium fluctuations during thermodiffusion in a polymer solution

- PhysicsThe European physical journal. E, Soft matter
- 2019

A phenomenological model is formulated that allows to relate the rate of growth of non-equilibrium fluctuations to the growth of the macroscopic concentration profile in the absence of arbitrary parameters.

### Shadowgraph Analysis of Non-equilibrium Fluctuations for Measuring Transport Properties in Microgravity in the GRADFLEX Experiment

- PhysicsMicrogravity Science and Technology
- 2016

In a fluid system driven out of equilibrium by the presence of a gradient, fluctuations become long-ranged and their intensity diverges at large spatial scales. This divergence is prevented by…

### Shadowgraph Analysis of Non-equilibrium Fluctuations for Measuring Transport Properties in Microgravity in the GRADFLEX Experiment

- Physics
- 2016

In a fluid system driven out of equilibrium by the presence of a gradient, fluctuations become long-ranged and their intensity diverges at large spatial scales. This divergence is prevented by…

### Giant Fluctuations Induced by Thermal Diffusion in Complex Liquids

- PhysicsMicrogravity Science and Technology
- 2020

The GRADFLEX experiment of ESA has shown that under microgravity conditions a stationary thermodiffusion process is accompanied by giant non-equilibrium fluctuations with size as large as the size of…

### Non-equilibrium concentration fluctuations in superparamagnetic nanocolloids

- PhysicsThe European physical journal. E, Soft matter
- 2017

It is found that the mass diffusion coefficient decreases in the presence of the external magnetic field and slowly rebounds after the magnetic field was turned off, and no correlation between the kinematic viscosity coefficient and the internal magnetic field is found.

### Dynamic scaling for the growth of non-equilibrium fluctuations during thermophoretic diffusion in microgravity

- PhysicsScientific Reports
- 2015

This work investigates the onset of non-equilibrium concentration fluctuations induced by thermophoretic diffusion in microgravity, a regime not accessible to analytical calculations but of great relevance for the understanding of several natural and technological processes.

### Fluctuating hydrodynamics of reactive liquid mixtures.

- PhysicsThe Journal of chemical physics
- 2018

The FHD approach provides remarkable computational efficiency over traditional reaction-diffusion master equation methods when the number of reactive molecules is large, while also retaining accuracy even when there are as few as ten reactive molecules per hydrodynamic cell.

### Low Mach Number Fluctuating Hydrodynamics for Electrolytes

- Physics
- 2016

We formulate and study computationally the low Mach number fluctuating hydrodynamic equations for electrolyte solutions. We are interested in studying transport in mixtures of charged species at the…

## References

SHOWING 1-10 OF 46 REFERENCES

### Long-wavelength nonequilibrium concentration fluctuations induced by the Soret effect.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2006

It is shown how one can obtain an exact expression for the nonequilibrium structure factor in the long-wavelength limit for a fluid layer with realistic impermeable and no-slip boundary conditions.

### Nonequilibrium fluctuations in the Rayleigh-Bénard problem for binary fluid mixtures

- PhysicsThe European physical journal. E, Soft matter
- 2004

A simpler small-Lewis-number approximation scheme is proposed, which is useful to represent nonequilibrium concentration fluctuations for mixtures with positive separation ratio, even close to (but below) the convective instability.

### Nonequilibrium Casimir-like Forces in Liquid Mixtures.

- PhysicsPhysical review letters
- 2015

In this Letter, a liquid mixture confined between two thermally conducting walls subjected to a stationary temperature gradient is considered, finding that nonequilibrium fluctuations in a mixture induce a Casimir-like force on the walls.

### Slowing-down of non-equilibrium concentration fluctuations in confinement

- Physics
- 2014

Fluctuations in a fluid are strongly affected by the presence of a macroscopic gradient making them long-ranged and enhancing their amplitude. While small-scale fluctuations exhibit diffusive…

### Fluctuating hydrodynamics of multispecies nonreactive mixtures.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2014

Good agreement with theory and experiment demonstrates that the formulation of the fluctuating Navier-Stokes equations for multispecies, nonreactive fluids is robust and can serve as a useful tool in the study of thermal fluctuations for mult ispecies fluids.

### Nonequilibrium Concentration Fluctuations in Binary Liquid Systems Induced by the Soret Effect

- Physics
- 2002

When a binary liquid system is brought into a stationary thermal nonequilibrium state by the imposition of a temperature gradient, the Soret effect induces long-range concentration fluctuations even…

### Hydrodynamic Fluctuations in Laminar Fluid Flow. I. Fluctuating Orr-Sommerfeld Equation

- Physics, Engineering
- 2011

In recent years it has become evident that fluctuating hydrodynamics predicts that fluctuations in nonequilibrium states are always spatially long ranged. In this paper we consider the application of…

### Fluctuation-induced pressures in fluids in thermal nonequilibrium steady states.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2014

Nonequilibrium temperature fluctuations induce nonequilibrium Casimir-like pressures proportional to the square of the temperature gradient, which causes a breakdown of the concept of local thermal equilibrium.