scholarly journals Instabilities in a drop-strip system: a simplified model

2012 ◽  
Vol 468 (2141) ◽  
pp. 1304-1324 ◽  
Author(s):  
Marco Rivetti ◽  
Sébastien Neukirch
Keyword(s):  
Experimental Data ◽  
Surface Tension ◽  
Energy Barrier ◽  
Applied Load ◽  
Liquid Drop ◽  
Elastic Beam ◽  
Simplified Model ◽  
Elastic Strip ◽  
System A ◽  
Surface Tension Forces

We study the deformation of an elastic strip by a liquid drop. At small enough scales, capillarity is the dominant fluid effect and surface tension forces may be sufficient to fold the beam, resulting in the wrapping of the drop by the beam. However, wrapping of the drop can be inhibited by the weight of the beam, which creates an energy barrier. The barrier can be overcome by input of kinetic energy in the form of impact of the drop. We introduce a semi-analytical model to study equilibria and their stability in three drop-beam systems: evaporation of a drop wetting and bending an elastic beam; impact of a drop on an elastic beam; lifting of a heavy elastic beam by a drop and we show the model reproduces experimental data. In relevant cases, we use the concept of suddenly applied load to discuss dynamic instabilities.

The Effect of Thermocapillary Flow on Heat Transfer in Dropwise Condensation

1970 ◽  
Vol 92 (1) ◽  
pp. 46-52 ◽  
Author(s):  
J. J. Lorenz ◽  
B. B. Mikic
Keyword(s):  
Heat Transfer ◽  
Surface Tension ◽  
Marangoni Number ◽  
Liquid Drop ◽  
Practical Interest ◽  
Dropwise Condensation ◽  
Internal Circulation ◽  
Vapor Interface ◽  
Surface Tension Forces ◽  
Finite Difference Techniques

The effect of fluid flow induced by surface tension forces on heat transfer through a drop was considered. The model is a hemispherical liquid drop growing on a flat isothermal-surface. The solution was obtained by finite-difference techniques for different values of the Marangoni number (Nm) associated with surface tension forces and the Biot number (Bi) associated with heat transfer at the liquid-vapor interface. The ranges of parameters covered by this investigation include the regimes of most practical interest for water. The results show that the contribution of internal circulation in the drops to the increase of heat transfer in dropwise condensation is insignificant.

Condensation of water vapour during supersonic expansion in nozzles

1966 ◽  
Vol 25 (3) ◽  
pp. 593-620 ◽  
Author(s):  
Philip G. Hill
Keyword(s):  
Experimental Data ◽  
Surface Tension ◽  
Liquid Drop ◽  
Accommodation Coefficient ◽  
Nucleation Theory ◽  
Growth Theory ◽  
Condensation Coefficient ◽  
Moist Air ◽  
Supersonic Expansion ◽  
Existing Data

Existing data on the condensation of steam and moist air in supersonic nozzles are compared with predictions based on nucleation and drop-growth theory. It is concluded that, if the surface tension is assumed independent of curvature, and the classical liquid-drop theory (based on a stationary liquid drop) is used, the theory is in general agreement with the data. The effects of uncertainties in cluster surface energy and also of the large corrections to nucleation theory due to the ‘gasification’ concept are examined. The gasification correction is in accord with experimental data only if the surface tension is considered to rise significantly with curvature. In neither case can the Tolman or Kirkwood–Buff equations be supported. A review of existing data shows that there is some question as to the appropriate value of the condensation coefficient but this is of little consequence as long as the accommodation coefficient for the liquid–vapour surface is taken to be unity. The usefulness of the nozzle experiments for testing the validity of nucleation theory is demonstrated.

INFLUENCE OF SURFACE TENSION FORCES ON FILMWISE CONDENSATION INTENSITY

2016 ◽  
Vol 7 (1-2) ◽  
pp. 93-102
Author(s):  
Vasily Buz ◽  
Konstantin Goncharov ◽  
Henry F. Smirnov
Keyword(s):  
Surface Tension ◽  
Surface Tension Forces

Isothermal and isobaric vapour-liquid equilibrium data in the tetrachloromethane-sec-butyl alcohol system

1983 ◽  
Vol 48 (9) ◽  
pp. 2446-2453 ◽  
Author(s):  
Jan Linek
Keyword(s):  
Experimental Data ◽  
Boiling Point ◽  
Butyl Alcohol ◽  
Correlation Equations ◽  
Wilson Equation ◽  
Liquid Equilibrium ◽  
Raoult’S Law ◽  
System A ◽  
Equilibrium Data ◽  
Alcohol System

Isothermal vapour-liquid equilibrium data at 65, 73 and 80 °C and isobaric ones at 101.3 kPa were measured in the tetrachloromethane-sec-butyl alcohol system. A modified circulation still of the Gillespie type was used for the measurements. Under the conditions of measurement, the system exhibits positive deviations from Raoult's law and minimum boiling-point azeotropes. The experimental data were fitted to a number of correlation equations, the most suitable being the Wilson equation.

scholarly journals Revisiting Kelvin equation and Peng–Robinson equation of state for accurate modeling of hydrocarbon phase behavior in nano capillaries

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ilyas Al-Kindi ◽  
Tayfun Babadagli
Keyword(s):  
Experimental Data ◽  
Surface Tension ◽  
Equation Of State ◽  
Phase Behavior ◽  
Pore Radius ◽  
Microfluidic Chips ◽  
Tight Sandstone ◽  
Kelvin Equation ◽  
Rock Samples ◽  
Robinson Equation

AbstractThe thermodynamics of fluids in confined (capillary) media is different from the bulk conditions due to the effects of the surface tension, wettability, and pore radius as described by the classical Kelvin equation. This study provides experimental data showing the deviation of propane vapour pressures in capillary media from the bulk conditions. Comparisons were also made with the vapour pressures calculated by the Peng–Robinson equation-of-state (PR-EOS). While the propane vapour pressures measured using synthetic capillary medium models (Hele–Shaw cells and microfluidic chips) were comparable with those measured at bulk conditions, the measured vapour pressures in the rock samples (sandstone, limestone, tight sandstone, and shale) were 15% (on average) less than those modelled by PR-EOS.

Effects of surface tension and viscosity on airway reopening

1990 ◽  
Vol 69 (1) ◽  
pp. 74-85 ◽  
Author(s):  
D. P. Gaver ◽  
R. W. Samsel ◽  
J. Solway
Keyword(s):  
Surface Tension ◽  
Fluid Viscosity ◽  
Opening Pressure ◽  
Viscous Forces ◽  
Considerable Portion ◽  
Airway Opening ◽  
Wall Compliance ◽  
Large Opening ◽  
Surface Tension Forces ◽  
The Relationship

We studied airway opening in a benchtop model intended to mimic bronchial walls held in apposition by airway lining fluid. We measured the relationship between the airway opening velocity (U) and the applied airway opening pressure in thin-walled polyethylene tubes of different radii (R) using lining fluids of different surface tensions (gamma) and viscosities (mu). Axial wall tension (T) was applied to modify the apparent wall compliance characteristics, and the lining film thickness (H) was varied. Increasing mu or gamma or decreasing R or T led to an increase in the airway opening pressures. The effect of H depended on T: when T was small, opening pressures increased slightly as H was decreased; when T was large, opening pressure was independent of H. Using dimensional analysis, we found that the relative importance of viscous and surface tension forces depends on the capillary number (Ca = microU/gamma). When Ca is small, the opening pressure is approximately 8 gamma/R and acts as an apparent “yield pressure” that must be exceeded before airway opening can begin. When Ca is large (Ca greater than 0.5), viscous forces add appreciably to the overall opening pressures. Based on these results, predictions of airway opening times suggest that airway closure can persist through a considerable portion of inspiration when lining fluid viscosity or surface tension are elevated.

Buckling Design of Axially Compressed Cylindrical Shells Based on Energy Barrier Approach

2021 ◽  
pp. 2150165
Author(s):  
Haigui Fan ◽  
Wenguang Gu ◽  
Longhua Li ◽  
Peiqi Liu ◽  
Dapeng Hu
Keyword(s):  
Experimental Data ◽  
Energy Barrier ◽  
Thin Shell ◽  
Design Method ◽  
Lightweight Design ◽  
Cylindrical Shells ◽  
Design Criterion ◽  
The Other ◽  
Shell Structures ◽  
Buckling Loads

Buckling design of axially compressed cylindrical shells is still a challenging subject considering the high imperfection-sensitive characteristic in this kind of structure. With the development of various design methods, the energy barrier concept dealing with buckling of imperfection-sensitive cylindrical shells exhibits a promising prospect in recent years. In this study, buckling design of imperfection-sensitive cylindrical shells under axial compression based on the energy barrier approach is systematically investigated. The methodology about buckling design based on the energy barrier approach is described in detail first taking advantage of the cylindrical shells whose buckling loads have been extensively tested. Then, validation and discussion about this buckling design method have been carried out by the numerical and experimental analyses on the cylindrical shells with different geometrical and boundary imperfections. Results in this study together with the available experimental data have verified the reliability and advantage of the buckling design method based on energy barrier approach. A design criterion based on the energy barrier approach is therefore established and compared with the other criteria. Results indicate that buckling design based on energy barrier approach can be used as an efficient way in the lightweight design of thin-shell structures.

Concentration Dependence of the Surface Tension of Three and Four-Component Systems with Peculiarities in the Surface Tension Isotherms of Lateral Binary Melts

2021 ◽  
Vol 1022 ◽  
pp. 194-202
Author(s):  
R.Kh. Dadashev ◽  
R.A. Kutuev
Keyword(s):  
Experimental Data ◽  
Surface Tension ◽  
Concentration Dependence ◽  
Experimental Error ◽  
Binary Systems ◽  
Experimental Studies ◽  
Study Results ◽  
Component Systems ◽  
Minimum Depth ◽  
Surface Tension Isotherms

The experimental study results of the melts concentration dependence of the surface tension of the four-component indium-tin-lead-bismuth system and its constituent binary systems of indium-tin, indium-lead, indium-bismuth, tin-lead, tin-bismuth, lead-bismuth are presented in the paper. It is shown that the concentration dependence of the melts surface tension of the In-Sn-Pb-Bi four-component system can be predicted from the data on ST (surface tension) values of lateral binary systems. Features in the ST isotherms in the form of a minimum are observed only in the indium-tin lateral system from all lateral binaries. A distinctive feature of the detected minimum is that the minimum depth slightly exceeds the experimental error. Therefore, in addition to the fact that the area of average compositions was studied more thoroughly, we carried out the surface tension measurements by two independent methods. The experimental data obtained by both methods coincide within the experimental error and indicate the extremum availability on ST isotherms. Thus, ST experimental studies by two independent methods confirmed the presence of a flat minimum on ST isotherms of the indium-tin binary system increasing the reliability of the obtained data. The obtained outcomes and their comparison with experimental data have shown that the considered models for predicting surface properties based on data due to similar properties of lateral binary systems adequately reflect the experimental dependences. However, the prediction model based on Kohler's method of excess values describes the experimental curves more accurately.

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