Particle motion driven by non-uniform thermodynamic forces
arXiv:1902.04801 · doi:10.1063/1.5085739
Abstract
We present a complete reciprocal description of particle motion inside multi-component fluids that extends the conventional Onsager formulation of non-equilibrium transport to systems where the thermodynamic forces are non-uniform on the colloidal scale. Based on the dynamic length and time scale separation in suspensions, the particle flux is shown to be related to the volume-averaged coupling between the Stokes flow tensor and the thermodynamic force density acting on the fluid. The flux is then expressed in terms of thermodynamic quantities that can be computed from the interfacial properties and equation of state of the colloids. Our results correctly describe diffusion and sedimentation, and suggest that force-free phoretic motion can occur even in the absence of interfacial interactions, provided that the thermodynamic gradients are non-uniform at the colloidal surface. In particular, we derive an explicit hydrodynamic form for the phoretic force resulting from these non-uniform gradients. The form is validated by the recovery of the Henry function for electrophoresis and the Ruckenstein term for thermophoresis.
The following article has been accepted by the Journal of Chemical Physics. After it is published, it will be found at https://aip.scitation.org/journal/jcp
References in corpus (8)
- Propulsion of a molecular machine by asymmetric distribution of reaction--products
- Transport in Charged Colloids Driven by Thermoelectricity
- Giant amplification of interfacially driven transport by hydrodynamic slip: diffusio-osmosis and beyond
- Flow pattern in the vicinity of self-propelling hot Janus particles
- Polarization of active Janus particles
- Thermophoresis of charged colloidal particles
- Fluctuating chemohydrodynamics and the stochastic motion of self-diffusiophoretic particles
- Van't Hoff's law for active suspensions: the role of the solvent chemical potential