Gradient dynamics model for chemically driven running drops
arXiv:2601.22962 · doi:10.1140/epjs/s11734-026-02296-w
Abstract
We present a thermodynamically consistent model for chemically driven running drops on a solid substrate with reversible substrate adsorption of a wettability-changing chemical species. We consider drops confined to a vertical gap, thereby allowing us to first obtain a gradient dynamics description of the closed system, corresponding to a set of coupled dynamical equations for the drop profile and the chemical concentration profiles of species on the substrate and in both fluids (drop, ambient medium). Chemostatting the species in the drop and the ambient medium, we then derive a reduced model for the dynamics of the drop and the adsorbate on the substrate. When the externally imposed chemical potentials are distinct, the system is driven away from thermodynamic equilibrium, allowing for sustained drop self-propulsion across the substrate due to a wettability contrast maintained by chemical reactions. We numerically study the resulting running drops and show how they emerge from drift-pitchfork bifurcations.
References in corpus (39)
- Propulsion of a molecular machine by asymmetric distribution of reaction--products
- Self Running Droplet: Emergence of Regular Motion from Nonequilibrium Noise
- Nonequilibrium Thermodynamics of Chemical Reaction Networks: Wisdom from Stochastic Thermodynamics
- Nonreciprocity as a generic route to traveling states
- Mode Selection in the Spontaneous Motion of an Alcohol Droplet
- Self-propulsion of chemically-active droplets
- Scalar Active Mixtures: The Non-Reciprocal Cahn-Hilliard Model
- Adhesion of membranes via receptor-ligand complexes: Domain formation, binding cooperativity, and active processes
- Long-wave theory of bounded two-layer films with a free liquid-liquid interface: Short- and long-time evolution
- Binding cooperativity of membrane adhesion receptors
- Spontaneous motion of a droplet coupled with a chemical wave
- Dynamical Model for Chemically Driven Running Droplets
- Self-propelled running droplets on solid substrates driven by chemical reactions
- Gradient dynamics models for liquid films with soluble surfactant
- Chemo-Sensitive Running Droplet
- Nonreciprocal pattern formation of conserved fields
- Gradient dynamics description for films of mixtures and suspensions - the case of dewetting triggered by coupled film height and concentration fluctuations
- Recent advances in and future challenges for mesoscopic hydrodynamic modelling of complex wetting
- Suppression of coarsening and emergence of oscillatory behavior in a Cahn-Hilliard model with nonvariational coupling
- Enzyme-enriched condensates show self-propulsion, positioning, and coexistence
- Nonreciprocal Cahn-Hilliard model emerges as a universal amplitude equation
- Thermodynamically consistent description of the hydrodynamics of free surfaces covered by insoluble surfactants of high concentration
- Nonequilibrium Thermodynamics of Non-Ideal Chemical Reaction Networks
- Equilibrium contact angle and adsorption layer properties with surfactants
- Gradient-dynamics model for liquid drops on elastic substrates
- Thin-Film Modelling of Resting and Moving Active Droplets
- Sessile drop evaporation in a gap -- crossover between diffusion-limited and phase transition-limited regime
- Criticality in Cell Adhesion
- Drops on polymer brushes -- advances in thin-film modelling of adaptive substrates
- Nonequilibrium Thermodynamics of Non-Ideal Reaction-Diffusion Systems: Implications for Active Self-Organization
- Self-consistent sharp interface theory of active condensate dynamics
- Self-similar finite-time singularity formation in degenerate parabolic equations arising in thin-film flows
- Stationary broken parity states in active matter models
- Coexistence of uniform and oscillatory states resulting from nonreciprocity and conservation laws
- Gradient dynamics approach to reactive thin-film hydrodynamics
- Mesoscopic hydrodynamic model for spreading, sliding and coarsening compound drops
- Chemomechanical motility modes of partially wetting liquid droplets
- What is a chemostat? Insights from hybrid dynamics and stochastic thermodynamics
- From bipedal to chaotic motion of chemically fueled partially wetting liquid drops