Line tension at high contact angle wetting: Contribution to interfacial energy at long distances (≫100Å) from the triple line contour

The wetting of Ag-5 wt.% CuO (Ag-5CuO) alloy on initial/CuO-coated zirconia toughened alumina (ZTA) composite ceramic in air was studied in detail. The results showed that the contact angle of the Ag-5CuO/ZTA system rapidly decreased from 81° at 970 °C to 45° at 990 °C during the heating process, however, moderate reductions in contact angle were observed in the subsequent heating and temperature holding stages. In comparison with the contact angle of pure Al2O3, an increment of about 4° of the stable contact angle of Ag-5CuO alloy on the heterogeneous ZTA was observed. The reaction between Al2O3 and CuO can reduce the damage of the CuO-rich liquid to ZrO2 in the ZTA substrate. Both oxygen and CuO were helpful in reducing the contact angle of Ag on ZTA and enhancing the bonding of the Ag/ZTA interface. The continuous CuO coating on ZTA and the monotectic liquid containing more CuO in the region near the triple line induced reductions of more than 40° and about 10° in the contact angle, respectively, between the initial and the CuO coating-improved wetting systems.

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The Pressure Drop and Dynamic Contact Angle of Motion of Triple-Lines in Hydrophobic Microchannels

ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels: Parts A and B ◽

10.1115/fedsm-icnmm2010-30677 ◽

2010 ◽

Author(s):

Dongin Yu ◽

Chiwoong Choi ◽

Moohwan Kim

Keyword(s):

Contact Angle ◽

Pressure Drop ◽

Liquid Film ◽

Dynamic Contact Angle ◽

Triple Line ◽

Dynamic Contact ◽

Superficial Velocity ◽

Channel Diameter ◽

Fluid Property ◽

Static Contact

At two-phase flow in microchannels, slug flow regime is different for wettability of surface. A slug in a hydrophilic microchannel has liquid film. However, a slug in a hydrophobic microchannel has no liquid film instead, the slug has triple-lines and makes higher pressure drop due to the motion of the triple-line. In previous researches, pressure drop of triple-line is depended of dynamic contact angle, channel diameter and fluid property. And, dynamic contact angle is depended of static contact angle, superficial velocity and fluid property. In order to understand the pressure drop of motion of triple-lines, pressure drop of slug with triple-lines in case of various diameters (0.546, 0.763, 1.018, 1.555, 2.075 mm), various fluids (D.I.water, D.I.water-1, 5, 10% ethanol mixture) and various superficial velocity (j = 0.01∼0.4 m/s) was measured. Dynamic contact angle was calculated from relation of the pressure drop of slug with triple-lines. Comparing with previous dynamic contact angle correlations, previous correlation underestimated dynamic contact angle in the region of this study. (10−4≤Ca≤10−3, 10−2≤We≤10−1, 68°≤θS≤110°)

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The impact of line tension on the contact angle of nanodroplets

Molecular Simulation ◽

10.1080/08927022.2013.828210 ◽

2013 ◽

Vol 40 (12) ◽

pp. 934-941 ◽

Cited By ~ 26

Author(s):

Hong Peng ◽

Greg R. Birkett ◽

Anh V. Nguyen

Keyword(s):

Contact Angle ◽

Line Tension ◽

The Impact

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COMPARABLE EFFECTS OF ADSORPTION AND LINE TENSION ON CONTACT ANGLE OF A NUCLEATED DROPLET ON A PARTIALLY WETTABLE SUBSTRATE

Interfacial Phenomena and Heat Transfer ◽

10.1615/interfacphenomheattransfer.2018025483 ◽

2017 ◽

Vol 5 (2) ◽

pp. 113-128 ◽

Cited By ~ 2

Author(s):

Dmitry V. Tatyanenko ◽

Alexander K. Shchekin

Keyword(s):

Contact Angle ◽

Line Tension

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Dependence of the Contact Angle on Adsorption at the Solid-Liquid Interface

ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels: Parts A and B ◽

10.1115/fedsm-icnmm2010-30180 ◽

2010 ◽

Author(s):

C. A. Ward

Keyword(s):

Surface Tension ◽

Contact Angle ◽

Pressure Range ◽

Line Tension ◽

Liquid Interface ◽

Fluid Interfaces ◽

Phase Line ◽

Three Phase ◽

Solid Liquid Interface ◽

Solid Liquid

A method for determining the surface tension of solid-fluid interfaces has been proposed. For a given temperature and fluid-solid combination, these surface tensions are expressed in terms of material properties that can be determined by measuring the amount of vapor adsorbed on the solid surface as a function of xV, the ratio of the vapor-phase pressure to the saturation-vapor pressure. The thermodynamic concept of pressure is shown to be in conflict with that of continuum mechanics, but is supported experimentally. This approach leads to the prediction that the contact angle, θ, can only exist in a narrow pressure range and that in this pressure range, the solid-vapor surface tension is constant and equal to the surface tension of the liquid-vapor interface, γLV. The surface tension of the solid-liquid interface, γSL, may be expressed in terms of measurable properties, γLV and θ: γSL = γLV(1 − cosθ). The value of θ is predicted to depend on both the pressure in the liquid at the three-phase, line x3L, and the three-phase line curvature, Ccl. We examine these predictions using sessile water droplets on a polished Cu surface, maintained in a closed, constant volume, isothermal container. The value of θ is found to depend on the adsorption at the solid-liquid interface, nSL = nSL(x3L,Ccl). The predicted value of θ is compared with that measured, and found to be in close agreement, but no effect of line tension is found.

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Line tension and reduction of apparent contact angle associated with electric double layers

Physics of Fluids ◽

10.1063/1.4892621 ◽

2014 ◽

Vol 26 (8) ◽

pp. 082105 ◽

Cited By ~ 9

Author(s):

Aaron Dörr ◽

Steffen Hardt

Keyword(s):

Contact Angle ◽

Line Tension ◽

Apparent Contact Angle ◽

Double Layers ◽

Electric Double Layers

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Special Wetting Behaviors on Canna Leaf and its Dependence with Microstructures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.779-780.64 ◽

2013 ◽

Vol 779-780 ◽

pp. 64-67

Author(s):

Xiao Hua Yang ◽

Jian Hua Xiao ◽

Jun Fei Ou

Keyword(s):

Contact Angle ◽

Contact Angle Hysteresis ◽

Lotus Leaf ◽

Micro Scale ◽

High Adhesion ◽

Rose Petal ◽

High Contact Angle ◽

Wetting Behaviors ◽

The Rose ◽

Rose Petal Effect

Like lotus leaf and rose petal, the canna leaf also has excellent super hydrophobicity.The purpose of this paper is to systematically study the super hydrophilicity of canna leaf. Using SEM to observe the morphology of the canna leaf, and analytical balance to measure the adhensive force between water droplet and the leaf . This paper shows that the first type of the canna leaf which has co-exsitence of the nanocrumb and micro-scale convex cells has the high contact angle and low contact angle hysteresis similar to lotus leaf. The another type on the leaf has high contact angle but high adhesion in a certain extent like the rose petal effect, whose microstructure unitarily simple has the micro convex cells, do not distributed anything of nanoscale.

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THE MODIFIED YOUNG'S EQUATION FOR THE CONTACT ANGLE OF A SMALL SESSILE DROP FROM AN INTERFACE DISPLACEMENT MODEL

International Journal of Modern Physics B ◽

10.1142/s0217979299003003 ◽

1999 ◽

Vol 13 (27) ◽

pp. 3255-3259 ◽

Cited By ~ 18

Author(s):

HARVEY DOBBS

Keyword(s):

Contact Angle ◽

Sessile Drop ◽

Unit Length ◽

Excess Free Energy ◽

Line Tension ◽

Rigid Substrate ◽

Three Phase ◽

Interface Displacement ◽

Displacement Model ◽

Young's Equation

We derive the modified Young's equation for the contact angle of a fluid droplet on a rigid substrate using an interface displacement model and identify the line tension with the excess free energy per unit length calculated previously for a straight three-phase contact line.

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