The non-equilibrium thermodynamics of active suspensions
arXiv:2505.21009 · doi:10.1088/1367-2630/adf660
Abstract
Active suspensions composed of self-propelled colloidal particles are considered. Their propulsion of is generated by chemical reactions occurring by heterogeneous catalysis and diffusiophoresis coupling the concentration gradients of reacting molecular species to the fluid velocity. By this mechanism, chemical free energy is transduced into mechanical motion. The non-equilibrium thermodynamics of such active suspensions is developed by explicitly taking into account the internal degrees of freedom of active particles, which are the Eulerian angles specifying their orientation. Accordingly, the distribution function of colloidal particles is defined in the six-dimensional configuration space of their position and their orientation, which fully characterises polar, nematic, and higher orientational orders in the active system. The local Gibbs and Euler thermodynamic relations are expressed in terms of the colloidal distribution function, the dynamics of which is ruled by a six-dimensional local conservation equation. All the processes contributing to the entropy production rate are derived from the local conservation and kinetic equations for colloids, molecular species, mass, linear momentum, and energy, identifying their thermodynamic forces, also called affinities, and their dissipative current densities. The non-equilibrium constitutive relations are obtained using the Curie symmetry principle and the Onsager-Casimir reciprocal relations based on microreversibility. In this way, all the mechanochemical coupling coefficients are completely determined for isothermal, incompressible, dilute suspensions composed of spherical Janus particles on the basis of the interfacial properties between the fluid solution and the solid particles and chemohydrodynamics. The complete expression of the entropy production rate is established for such active systems.
References in corpus (27)
- Active Particles in Complex and Crowded Environments
- Self-motile colloidal particles: from directed propulsion to random walk
- The Mechanics and Statistics of Active Matter
- Motility-Induced Phase Separation
- Designing phoretic micro- and nano-swimmers
- Electrokinetic Effects in Catalytic Pt-Insulator Janus Swimmers
- Probing the nanohydrodynamics at liquid-solid interfaces using thermal motion
- A Classical Density-Functional Theory for Describing Water Interfaces
- Theories of Binary Fluid Mixtures: From Phase-Separation Kinetics to Active Emulsions
- Phoretic Motion of Spheroidal Particles Due To Self-Generated Solute Gradients
- Irreversibility and biased ensembles in active matter: Insights from stochastic thermodynamics
- Entropy production of active particles and for particles in active baths
- Experimental Observation of Flow Fields Around Active Janus Spheres
- Chemistry in Motion: Tiny Synthetic Motors
- Multiple phoretic mechanisms in the self-propulsion of a Pt-insulator Janus swimmer
- Thermodynamics of active field theories: Energetic cost of coupling to reservoirs
- Fluctuating chemohydrodynamics and the stochastic motion of self-diffusiophoretic particles
- Mechanochemical fluctuation theorem and thermodynamics of self-phoretic motors
- Thermodynamics and statistical mechanics of chemically-powered synthetic nanomotors
- Thermodynamics of active matter: Tracking dissipation across scales
- Near-wall nanovelocimetry based on Total Internal Reflection Fluorescence with continuous tracking
- The measurement of Navier slip on individual nanoparticles in liquid
- Active matter, microreversibility, and thermodynamics
- Microscopic and continuum descriptions of Janus motor fluid flow fields
- Thermodynamic Approach to the Self-Diffusiophoresis of Colloidal Janus Particles
- Molecular theory of Langevin dynamics for active self-diffusiophoretic colloids
- Microscopic theory of a Janus motor in a non-equilibrium fluid: Surface hydrodynamics and boundary conditions