A Modified Smoothed Particle Hydrodynamics Approach for Modelling Dynamic Contact Angle Hysteresis

TL;DR

This paper introduces a modified smoothed particle hydrodynamics (SPH) model incorporating a viscous force at the liquid-solid interface to accurately simulate dynamic contact angle hysteresis in multiphase flows, aligning well with experimental data.

Contribution

The work develops a new viscous force formulation within SPH to model rate-dependent contact line dynamics, enhancing simulation accuracy for wetting phenomena.

Findings

The modified SPH model accurately reproduces dynamic contact angles.

Interfacial viscous force influences contact angle monotonically.

Results align with experimental and theoretical predictions.

Abstract

Dynamic wetting plays an important role in the physics of multiphase flow, and has significant influence on many industrial and geotechnical applications. In this work, a modified smoothed particle hydrodynamics (SPH) model is employed to simulate surface tension, contact angle, and dynamic wetting effects. The wetting and dewetting phenomena are simulated in a capillary tube, where the liquid particles are raised or withdrawn by a shifting substrate. The SPH model is modified by introducing a newly-developed viscous force formulation at liquid-solid interface to reproduce the rate-dependent behaviour of moving contact line. Dynamic contact angle simulations with interfacial viscous force are conducted to verify the effectiveness and accuracy of this new formulation. In addition, the influence of interfacial viscous force with different magnitude on contact angle dynamics is examined by empirical power law correlations, and the derived constants suggest the dynamic contact angle changes monotonically with interfacial viscous force. The simulation results are consistent with the experimental observations and theoretical predictions, implying that the interfacial viscous force can be associated with slip length of flow and microscopic surface roughness. This work has demonstrated that the modified SPH model can successfully account for the rate-dependent effects of moving contact line, and can be used for realistic multiphase flow simulation under dynamic conditions.