A dynamic optimization strategy is presented to generate customized equations of state (EOS) for the numerical simulation non-ideal fluids at high density ratio. While stable branches analytical EOS are preserved, spinodal region self-tuned during simulation, in order compensate errors caused by discretization phase space. The employed permits readily setting sound speeds gas and liquid phases, thus allowing with (1 : 10 1 1000) compressibility ratios (250 1–25000 1). present technique...

We study numerically the hydrodynamics of dip coating from a suspension and report mechanism for colloidal assembly pattern formation on smooth uniform substrates. Below critical withdrawal speed substrate, capillary forces required to deform meniscus prevent particles entering film. Capillary are overcome by hydrodynamic drag only after minimum number organize in close-packed within meniscus. Once film, formed moves at nearly rapidly separates next assembly. The interplay between can thus...

The adsorption of a colloidal particle at fluid interface is studied theoretically and numerically, documenting distinctly different relaxation regimes. perfectly smooth characterized by fast exponential to thermodynamic equilibrium where the interfacial free energy reaches global minimum. short time given ratio viscous damping capillary forces. Physical and/or chemical heterogeneities, however, can result in multiple minima giving rise metastability. In presence metastable states we observe...

Solving the Boltzmann–BGK equation, we investigate a flow generated by an infinite plate oscillating with frequency ω. The geometrical simplicity of problem allows solution in entire range dimensionless variation 0 ≤ ωτ ∞, where τ is properly defined relaxation time. A transition from viscoelastic behaviour Newtonian fluid (ωτ → 0) to purely elastic dynamics limit ∞ discovered. relation derived solutions nanofluidics demonstrated on solvable example ‘plane oscillator’. results formulae...

Solvent-induced interactions produce the kinetic trapping of nanoparticles at nanoscale particle–wall separations.

Nanoparticle suspensions hold promise to transform functionality of next-generation electrochemical systems including batteries, capacitors, wastewater treatment, and sensors, challenging the limits existing models. Classical solution-based electrochemistry assumes that charge is transported transferred by point-like carriers. Herein, we examine a model aqueous suspension nondissolvable electroactive nanoparticles over wide concentration range using rotating disk electrode. Past rotation...

We present a model based on the lattice Boltzmann equation that is suitable for simulation of dynamic wetting. The capable exhibiting fundamental interfacial phenomena such as weak adsorption fluid solid substrate and presence thin surface film within which disjoining pressure acts. Dynamics in this film, tightly coupled with hydrodynamics bulk, determine macroscopic properties primary interest: hydrodynamic slip; equilibrium contact angle; static hysteresis angles. pseudo-potentials...

The adsorption of single colloidal microparticles (0.5--1 $\mu$m radius) at a water-oil interface has been recently studied experimentally using digital holographic microscopy [Kaz \textit{et al., Nat. Mater.}, 2012, \textbf{11}, 138--142]. An initially fast dynamics driven by capillary forces is followed an unexpectedly slow relaxation to equilibrium that logarithmic in time and can span hours or days. kinetics attributed the presence surface "defects" with nanoscale dimensions (1--5\,nm)...

Micro-or nano-structurally roughened solid surfaces exhibit a rich variety of wetting behavior types, ranging from superhydro- or superoleophobicity to superoleophilicity. Depending on their material chemistry, the scale and morphology roughness even application external electric fields, apparent wettability can be significantly modified giving rise challenging technological applications by exploiting associated capillary phenomena at micrometer scale. Certain applications, however, are...

Abstract Dual‐scale hierarchical structures with regular microscale patterns and varying degree of nanoscale crystalline order are synthesized on physically chemically homogeneous substrates by evaporative self‐assembly a suspension DNA‐functionalized nanoparticles (NPs) charged core shell. For certain NP concentration range, periodic concentric rings in stripe‐like micropattern produced over macroscale surface areas an monolayer hexagonal lattice structure at the nanoscale. The stripe...

Using fluorescence microscopy we study the adsorption of single latex microparticles at a water/water interface between demixing aqueous solutions polymers, generally known as water-in-water emulsion. Similar molecular liquids have exhibited an extremely slow relaxation preventing observation expected equilibrium states. This phenomenon has been attributed to "long-lived" metastable states caused by significant energy barriers $\Delta{\cal F}\sim \gamma A_d\gg k_B T$ induced high interfacial...

Nanoparticles with different surface morphologies that straddle the interface between two immiscible liquids are studied via molecular dynamics simulations. The methodology employed allows us to compute interfacial free energy at angular orientations of nanoparticle. Due their atomistic nature, nanoparticles present both microscale and macroscale geometrical features cannot be accurately modeled as a perfectly smooth body (e.g., spheres cylinders). Under certain physical conditions, can...

Surface roughness can play a critical role in dynamic wetting processes like imbibition and drainage of capillaries. In the presence nanoscale roughness, The shear-driven microscale capillary grooves exhibits regimes that cannot be described by solely considering hydrodynamic effects. Thermal motion surface ``characterized AFM'' induce rates predicted Kramers theory thermally activated transitions.

In this work, closure of the Boltzmann--Bhatnagar-Gross-Krook (Boltzmann-BGK) moment hierarchy is accomplished via projection distribution function $f$ onto a space ${\mathbb{H}}^{N}$ spanned by $N$-order Hermite polynomials. While successive order approximations retain an increasing number leading-order moments $f$, presented procedure produces (single) partial-differential equations providing exact analytical description hydrodynamics rendered ($N$-order) lattice Boltzmann-BGK (LBBGK)...

In this work, we employ a kinetic-theory-based approach to predict the hydrodynamic forces on electromechanical resonators operating in gaseous media. Using Boltzmann–BGK equation, investigate influence of resonator geometry fluid resistance entire range non-dimensional frequency variation 0 ≤ τω ∞; here relaxation time τ = μ/ p is determined by gas viscosity μ and pressure at thermodynamic equilibrium, ω (angular) oscillation frequency. Our results capture two important aspects recent...

Theoretical analysis and fully atomistic molecular dynamics simulations reveal a Brownian ratchet mechanism by which thermal fluctuations drive the net displacement of immiscible liquids confined in channels or pores with micro- nanoscale dimensions. The thermally driven is induced surface nanostructures directional asymmetry can occur against direction action wetting capillary forces. Mean rates are predicted via analytical solution Smoluchowski diffusion equation for position probability...

A complex dynamics of a shear wave decay, defined as an initial value problem u(y,0)=U sin(ky)i, where i is unit vector in the x-direction, investigated entire range Weissenberg–Knudsen number (Wi=τνk2=τ2c2k2) variation 0≤Wi≤∞, τ and c are fluid relaxation time speed sound vicinity thermodynamic equilibrium, respectively. It shown that limit Wi⪡1, decay purely viscous process obeying parabolic diffusion equation. When Wi⪢1, completely new regime emerges, flow behaves dissipative transverse...

Using molecular dynamics simulations, we investigate the fate of a nanoparticle deposited on solid surface as liquid-liquid interface moves past it, depending wetting by two liquids and magnitude driving force. Interfacial pinning is observed below critical value Above force for large contact angle values observe stick-slip motion, with intermittent interfacial particle sliding at interface. At low angles that rolling precedes detachment, which indicates importance dynamic effects not...