Smoothing of contact lines in spreading droplets by trisiloxane surfactants and its relevance for superspreading

Rolf E. Isele-Holder; Benjamin Berkels; Ahmed E. Ismail

doi:10.1039/c4sm02298j

Smoothing of contact lines in spreading droplets by trisiloxane surfactants and its relevance for superspreading

Soft Matter ◽

10.1039/c4sm02298j ◽

2015 ◽

Vol 11 (22) ◽

pp. 4527-4539 ◽

Cited By ~ 12

Author(s):

Rolf E. Isele-Holder ◽

Benjamin Berkels ◽

Ahmed E. Ismail

Keyword(s):

Contact Lines ◽

Droplet Spreading ◽

Trisiloxane Surfactants ◽

Liquid Vapor

Trisiloxane surfactants allow for smooth transfer of surfactant between the liquid–vapor and liquid–substrate interfaces, enabling faster droplet spreading.

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Numerical Investigation on the Regime of Cavitation Shedding and Collapse During the Water-Exit of Submerged Projectile

Journal of Fluids Engineering ◽

10.1115/1.4044831 ◽

2019 ◽

Vol 142 (1) ◽

Author(s):

Ying Chen ◽

Zhaoxin Gong ◽

Jie Li ◽

Xin Chen ◽

Chuanjing Lu

Keyword(s):

Water Surface ◽

High Speed ◽

Leading Edge ◽

Joint Effect ◽

Contact Lines ◽

Moving Wall ◽

Eddy Simulation ◽

Cavity Closure ◽

Water Exit ◽

Liquid Vapor

Abstract Cavitation may develop on upward-launched submerged objects approaching sea surface with high speed. In this work, the cavitation shedding and collapse during the water-exit of an axisymmetric projectile is investigated using large eddy simulation (LES). High resolution is guaranteed by carefully fulfilling the requisites of y+<1, Δx+<100, and Δz+<40 to resolve at least 80% of the turbulent kinetic energy. The result indicates that the cavity in growth is always undeveloped as the ambient hydrostatic pressure keeps decreasing. The cavity is pushed by the water surface to shed downward and keep shrinking until its final collapse. The vapor inside cavity during the water-exit process is separated by a layer of water so as not to mix with the air. The front of the re-entrant jet barely catches up with the moving wall, and the cavity is pinched off by the joint effect of the jet front and water surface. It is also found that the angle of attack (AOA) generates inversely inclined liquid-vapor contact lines of the cavity leading edge and cavity closure. The advancing contact lines finally intersect on the pressure side to make the cavity break off, which can cause noticeable pressure impulse on the break-off spot. The pressure feature of the water-exit cavitation evolution is studied with intensively arranged monitor points on the wall, which can sense pressure peaks when the liquid-vapor contact lines sweep over them. The instantaneous high pressure induced by cavitation collapse is resolved.

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Experimental Characterization of the Reliability of 3-Terminal Dual-Damascene Copper Interconnect Trees

MRS Proceedings ◽

10.1557/proc-716-b8.13 ◽

2002 ◽

Vol 716 ◽

Cited By ~ 4

Author(s):

C. L. Gan ◽

C. V. Thompson ◽

K. L. Pey ◽

W. K. Choi ◽

F. Wei ◽

...

Keyword(s):

Stress Conditions ◽

Experimental Characterization ◽

Contact Lines ◽

Tree Structures ◽

Similar Test ◽

Dual Damascene ◽

Copper Interconnect ◽

Test Conditions

AbstractElectromigration experiments have been carried out on simple Cu dual-damascene interconnect tree structures consisting of straight via-to-via (or contact-to-contact) lines with an extra via in the middle of the line. As with Al-based interconnects, the reliability of a segment in this tree strongly depends on the stress conditions of the connected segment. Beyond this, there are important differences in the results obtained under similar test conditions for Al-based and Cu-based interconnect trees. These differences are thought to be associated with variations in the architectural schemes of the two metallizations. The absence of a conducting electromigrationresistant overlayer in Cu technology, and the possibility of liner rupture at stressed vias lead to significant differences in tree reliabilities in Cu compared to Al.

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