Fast Evaporation of Spreading Droplets of Colloidal Suspensions

蒸发 Péclet编号 咖啡环效应 粒子(生态学) 润滑理论 对流 机械 传质 工作(物理) 扩散 粘度 润滑 悬挂(拓扑) 流变学 化学物理 化学 胶体 航程(航空) 材料科学 热力学 物理 复合材料 物理化学 数学 地质学 海洋学 纯数学 同伦
作者
Kara L. Maki,Satish Kumar
出处
期刊:Langmuir [American Chemical Society]
卷期号:27 (18): 11347-11363 被引量:136
标识
DOI:10.1021/la202088s
摘要

When a coffee droplet dries on a countertop, a dark ring of coffee solute is left behind, a phenomenon often referred to as the coffee-ring effect. A closely related yet less-well-explored phenomenon is the formation of a layer of particles, or skin, at the surface of the droplet during drying. In this work, we explore the behavior of a mathematical model that can qualitatively describe both phenomena. We consider a thin axisymmetric droplet of a colloidal suspension on a horizontal substrate undergoing spreading and evaporation. In contrast to prior work, precursor films (rather than pinned contact lines) are present at the droplet edge, and evaporation is assumed to be limited by how quickly molecules can transfer out of the liquid phase (rather than by how quickly they can diffuse through the gas phase). The lubrication approximation is applied to simplify the mass and momentum conservation equations, and the colloidal particles are allowed to influence the droplet rheology through their effect on the viscosity. By describing the transport of the colloidal particles with the full convection-diffusion equation, we are able to capture depthwise gradients in particle concentration and thus describe skin formation, a feature neglected in prior models of droplet evaporation. The highly coupled model equations are solved for a range of problem parameters using a finite-difference scheme based on a moving overset grid. The presence of evaporation and a large particle Peclet number leads to the accumulation of particles at the liquid-air interface. Whereas capillarity creates a flow that drives particles to the droplet edge to produce a coffee ring, Marangoni flows can compete with this and promote skin formation. Increases in viscosity due to particle concentration slow down droplet dynamics and can lead to a reduction in the spreading rate.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
大幅提高文件上传限制,最高150M (2024-4-1)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
刚刚
1秒前
2秒前
有趣的灵魂完成签到,获得积分10
2秒前
2秒前
2秒前
3秒前
24完成签到,获得积分20
3秒前
tcklikai完成签到,获得积分10
3秒前
Lyl完成签到,获得积分10
4秒前
5秒前
传奇3应助朝夕采纳,获得10
5秒前
在水一方应助嘿哟采纳,获得10
6秒前
KYN发布了新的文献求助10
6秒前
6秒前
sunny完成签到,获得积分10
7秒前
繁荣的映雁完成签到,获得积分10
7秒前
cui发布了新的文献求助10
7秒前
Maker发布了新的文献求助10
8秒前
8秒前
24发布了新的文献求助10
9秒前
9秒前
10秒前
10秒前
汉堡包应助名字是乱码采纳,获得10
11秒前
开朗依霜发布了新的文献求助30
11秒前
英俊的铭应助打屁飞采纳,获得10
11秒前
小二郎应助学医自救采纳,获得10
12秒前
coeds完成签到,获得积分10
12秒前
13秒前
孤独的AD钙完成签到,获得积分10
13秒前
zz完成签到,获得积分10
14秒前
小高完成签到,获得积分10
15秒前
spd发布了新的文献求助10
15秒前
学习快乐应助Maker采纳,获得10
15秒前
LNN发布了新的文献求助10
16秒前
花木宝宝发布了新的文献求助10
16秒前
NexusExplorer应助panfan采纳,获得10
16秒前
Mike001发布了新的文献求助10
16秒前
css完成签到,获得积分10
16秒前
高分求助中
Manual of Clinical Microbiology, 4 Volume Set (ASM Books) 13th Edition 1000
Sport in der Antike 800
Aspect and Predication: The Semantics of Argument Structure 666
De arte gymnastica. The art of gymnastics 600
少脉山油柑叶的化学成分研究 530
Electronic Structure Calculations and Structure-Property Relationships on Aromatic Nitro Compounds 500
Berns Ziesemer - Maos deutscher Topagent: Wie China die Bundesrepublik eroberte 500
热门求助领域 (近24小时)
化学 材料科学 医学 生物 有机化学 工程类 生物化学 纳米技术 物理 内科学 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 电极 光电子学 量子力学
热门帖子
关注 科研通微信公众号,转发送积分 2413317
求助须知:如何正确求助?哪些是违规求助? 2107119
关于积分的说明 5325371
捐赠科研通 1834541
什么是DOI,文献DOI怎么找? 914082
版权声明 560992
科研通“疑难数据库(出版商)”最低求助积分说明 488793