Journal ArticleDOI
The dynamics of the spreading of liquids on a solid surface. Part 2. Surfactants
Reads0
Chats0
TLDR
In this paper, the effect of the presence of a surfactant on the dynamics involved in the movement of the contact line when one liquid displaces an immiscible second liquid where both are in contact with a smooth solid surface is discussed.Abstract:
A theoretical study is made of the effect of the presence of a surfactant on the dynamics involved in the movement of the contact line when one liquid displaces an immiscible second liquid where both are in contact with a smooth solid surface. The general procedure of solution is described for a general model for slip between solid and liquid near the contact line and also for a general macroscopic geometry. For small capillary number and for small values of the length over which slip occurs, it is shown, using singular perturbation analysis, that either 2 or 3 regions of expansion are necessary depending on the type of limiting process being considered. Solutions are obtained for both situations but for the more important three-region expansion case (where there can be large dynamic effects), a detailed discussion is given of the manner in which the observable macroscopic contact angle is shown to depend on the contact line velocity and on surfactant concentration. The conditions of validity for the theory are also discussed.read more
Citations
More filters
Journal ArticleDOI
Wetting and Spreading
TL;DR: In this article, the surface forces that lead to wetting are considered, and the equilibrium surface coverage of a substrate in contact with a drop of liquid is examined, while the hydrodynamics of both wetting and dewetting is influenced by the presence of the three-phase contact line separating "wet" regions from those that are either dry or covered by a microscopic film.
Journal ArticleDOI
The physics of moving wetting lines
TL;DR: This paper seeks to offer a status report on the current approaches to wetting dynamics, to briefly review each of theCurrent approaches, to illustrate their successes and limitations as revealed by experiment and simulation, and to suggest ways in which the different aspects of wetts dynamics might be investigated in the future.
Journal ArticleDOI
Contact angle hysteresis: a review of fundamentals and applications
TL;DR: In this paper, the authors introduce the formalism and models for implementing contact angle hysteresis into relevant physical phenomena, such as sliding drops, coffee stain phenomenon (in general evaporative self-assembly), and curtain and wire coating techniques.
Journal ArticleDOI
Numerical modeling of multiphase flows in microfluidics and micro process engineering: a review of methods and applications
TL;DR: A comprehensive review of numerical methods and models for interface resolving simulations of multiphase flows in microfluidics and micro process engineering is presented in this paper, where three common approaches in the sharp interface limit, namely the volume-of-fluid method with interface reconstruction, the level set method and the front tracking method, as well as methods with finite interface thickness such as color function based methods and the phase-field method are discussed.
Journal ArticleDOI
A variational approach to moving contact line hydrodynamics
TL;DR: In this article, a variational derivation of the generalized Navier boundary condition (GNBC) was proposed to solve the problem of incompatibility between the moving contact line and the no-slip boundary condition, which leads to a nonintegrable singularity.
References
More filters
Journal ArticleDOI
On the Spreading of Liquids on Solid Surfaces: Static and Dynamic Contact Lines
TL;DR: In this article, it is shown that the mutual interaction between the three materials in the immediate vicinity of a contact line can significantly affect the statics as well as the dynamics of an entire flow field.
Journal ArticleDOI
The dynamics of the spreading of liquids on a solid surface. Part 1. Viscous flow
TL;DR: In this paper, the dynamics involved in the movement of the contact line when one liquid displaces an immiscible second liquid where both are in contact with a smooth solid surface are investigated.
Journal ArticleDOI
A moving fluid interface. Part 2. The removal of the force singularity by a slip flow
TL;DR: In this article, the effect of a slip coefficient on the flow in the neighbourhood of the contact line was examined, and the contribution of the vicinity of a contact line to the force on the boundary was obtained.