1216 Analytical Study of Reacting Forces of Liquid Meniscus Bridge : Effects of Dynamic Behavior of Contact Line and Contact Angle and Analysis of Liquid Meniscus Bridge Configuration

2013 ◽  
Vol 2013.51 (0) ◽  
pp. _1216-1_-_1216-2_
Author(s):  
Tadahiko ITANI ◽  
Hiroshige MATSUOKA ◽  
Shigehisa FUKUI
Keyword(s):  
Contact Angle ◽  
Dynamic Behavior ◽  
Contact Line ◽  
Analytical Study ◽  
Liquid Meniscus

scholarly journals Wetting of doubly periodic rough surfaces in Wenzel’s regime

2018 ◽  
Vol 145 ◽  
pp. 03006
Author(s):  
Stanimir Iliev ◽  
Nina Pesheva ◽  
Pavel Iliev
Keyword(s):  
Contact Angle ◽  
Contact Line ◽  
Numerical Study ◽  
Rough Surfaces ◽  
Contact Angle Hysteresis ◽  
Stick Slip ◽  
Liquid Meniscus ◽  
Three Phase ◽  
Mutual Disposition ◽  
Physical Defects

In this work we present preliminary results from our numerical study of the shapes of a liquid meniscus in contact with doubly sinusoidal rough surfaces in Wenzel’s wetting regime. Using the full capillary model we obtain the advancing and the receding equilibrium meniscus shapes for a broad interval of surface roughness factors. The contact angle hysteresis is obtained when the three-phase contact line is located on one row (block case) or several rows (kink case) of physical defects. We find that depending on the mutual disposition of the contact line and the lattice of periodic defects, different stick-slip behaviors of the contact line depinning mechanism appear, leading to different values of the contact angle hysteresis.

Evolution of Liquid Meniscus Shape in a Capillary Tube

2007 ◽  
Vol 129 (8) ◽  
pp. 957-965 ◽  
Author(s):  
Shong-Leih Lee ◽  
Hong-Draw Lee
Keyword(s):  
Contact Angle ◽  
Contact Line ◽  
Capillary Rise ◽  
Stress Singularity ◽  
Dynamic Contact Angle ◽  
Dynamic Contact ◽  
Surface Flow ◽  
Force Balance ◽  
Liquid Meniscus ◽  
Meniscus Shape

There are still many unanswered questions related to the problem of a capillary surface rising in a tube. One of the major questions is the evolution of the liquid meniscus shape. In this paper, a simple geometry method is proposed to solve the force balance equation on the liquid meniscus. Based on a proper model for the macroscopic dynamic contact angle, the evolution of the liquid meniscus, including the moving speed and the shape, is obtained. The wall condition of zero dynamic contact angle is allowed. The resulting slipping velocity at the contact line resolves the stress singularity successfully. Performance of the present method is examined through six well-documented capillary-rise examples. Good agreements between the predictions and the measurements are observable if a reliable model for the dynamic contact angle is available. Although only the capillary-rise problem is demonstrated in this paper, the concept of this method is equally applicable to free surface flow in the vicinity of a contact line where the capillary force dominates the flow.

Surface Topography Induced Ultrahydrophobic Behavior: Effect of Three-Phase Contact Line Topology

2006 ◽  
Author(s):  
Neeharika Anantharaju ◽  
Mahesh Panchagnula ◽  
Wayne Kimsey ◽  
Sudhakar Neti ◽  
Svetlana Tatic-Lucic
Keyword(s):  
Contact Angle ◽  
Contact Line ◽  
Anomalous Behavior ◽  
Contact Angles ◽  
Wet Etching ◽  
Surface Geometry ◽  
Wetting Behavior ◽  
Void Fractions ◽  
Three Phase ◽  
Receding Contact

The wettability of silicon surface hydrophobized using silanization reagents was studied. The advancing and receding contact angles were measured with the captive needle approach. In this approach, a drop under study was held on the hydrophobized surface with a fine needle immersed in it. The asymptotic advancing and receding angles were obtained by incrementally increasing the volume added and removed, respectively, until no change in angles was observed. The values were compared with the previously published results. Further, the wetting behavior of water droplets on periodically structured hydrophobic surfaces was investigated. The surfaces were prepared with the wet etching process and contain posts and holes of different sizes and void fractions. The surface geometry brought up a scope to study the Wenzel (filling of surface grooves) and Cassie (non filling of the surface grooves) theories and effects of surface geometry and roughness on the contact angle. Experimental data point to an anomalous behavior where the data does not obey either Wenzel or Cassie type phenomenology. This behavior is explained by an understanding of the contact line topography. The effect of contact line topography on the contact angle was thus parametrically studied. It was also inferred that, the contact angle increased with the increase in void fraction. The observations may serve as guidelines in designing surfaces with the desired wetting behavior.

scholarly journals Analytical study of the dynamic behavior of geometrically nonlinear shaft-disk rotor systems

2011 ◽  
Vol 12 (6) ◽  
pp. 433-443
Author(s):  
Muhammad Rizwan Shad ◽  
Guilhem Michon ◽  
Alain Berlioz
Keyword(s):  
Dynamic Behavior ◽  
Analytical Study ◽  
Geometrically Nonlinear ◽  
Rotor Systems
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