It is well known that surface tension is dependent on temperature, and thus a nonuniform temperature may cause thermocapillary flow which is referred to as the Marangoni effect. For a thin liquid-air film confined between a flat hot plate and a topographical cold template, it undergoes deformation due to thermocapillary flow. This phenomenon is termed as thermocapillary patterning, and has been used to fabricate micro- and nanostructure in polymer films. In most cases, the obtained structure conforms to the template; i.e., it can be considered as a replication technique. In this paper, we developed a two-phase flow numerical model based on the phase field to study the dynamic process of thermocapillary patterning. As a remeshing-free method, the phase field enables the incorporation of thermal field and multiphase flow with free surface deformation. The numerical model was employed to study the dynamic process of thermocapillary patterning. Meanwhile, the effects of some parameters, e.g., temperature, geometry parameters, and contact angle, were also investigated.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1103/PhysRevE.106.015111 | DOI Listing |
Phys Rev E
September 2024
School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD 4001, Australia.
The study of viscous thin film flow has led to the development of highly nonlinear partial differential equations that model how the evolution of the film height is affected by different forces. We investigate a model of interaction between surface tension and the thermocapillary Marangoni effect, with a particular focus on the long-time limit. In this limit, the model predicts the creation of an infinite cascade of successively smaller satellite droplets near points where the film thickness vanishes.
View Article and Find Full Text PDFLangmuir
July 2024
Photonics and Microfluidics Laboratory, X-BIO Institute, University of Tyumen, Tyumen 625003, Russia.
The production of particle deposits with a desired distribution geometry has significant potential for materials science, printing, and coating technologies. Most methods for achieving well-defined assemblies rely on the spontaneous evaporation of colloidal solutions on substrates with predetermined properties, or on precise control of particle arrangement by external stimuli. Here, we present a combined method that enables the production of centimeter-scale microparticle deposits with a desired geometric shape.
View Article and Find Full Text PDFMaterials (Basel)
March 2024
Metallurgy Department, Montanuniversitaet of Leoben, Franz-Josef-Str. 18, A-8700 Leoben, Austria.
Due to the high computational costs of the Eulerian multiphase model, which solves the conservation equations for each considered phase, a two-phase mixture model is proposed to reduce these costs in the current study. Only one single equation for each the momentum and enthalpy equations has to be solved for the mixture phase. The Navier-Stokes and energy equations were solved using the 3D finite volume method.
View Article and Find Full Text PDFMicromachines (Basel)
September 2023
School of Mechanical Engineering, Xiangtan University, Xiangtan 411105, China.
Laser polishing is an emerging efficient technique to remove surface asperity without polluting the environment. However, the insufficient understanding of the mechanism of laser polishing has limited its practical application in industry. In this study, a dual-beam laser polishing experiment was carried out to reduce the roughness of a primary Ti6Al4V sample, and the polishing mechanism was well studied using simulation analysis.
View Article and Find Full Text PDFSoft Matter
July 2023
Optofluidics and Interface Science Laboratory, Department of Physics, National Institute of Technology Calicut, Kozhikode, India.
The generation and control of microscale flows are crucial for fundamental as well as applied aspects of microfluidics. Commonly employed strategies for creating microflows are based on electric field, magnetic field, surface tension, temperature, pressure, light, Among them, light as an external stimulus is gaining increased attention as it offers non-contact actuation, high spatial and temporal resolution, tunable wavelength and intensity, ease of miniaturization, and fast response. Optically tuning the surface tension is promising because a surface tension gradient of a few mN m along the liquid surface is sufficient to create a strong Marangoni flow.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!