干旱区生态环境知识资源中心(Arid): Evolution of meniscus structures in hydrophobic granular systems

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DOI	10.1016/j.jhydrol.2021.126954
	Evolution of meniscus structures in hydrophobic granular systems
	Karatza, Zeynep; Buckman, Jim; Medero, Gabriela M.; Beckett, Christopher T. S.
通讯作者	Karatza, Z (corresponding author), Univ Edinburgh, Sch Engn, Inst Infrastruct & Environm, Edinburgh EH9 3JL, Midlothian, Scotland.
来源期刊	JOURNAL OF HYDROLOGY
ISSN	0022-1694
EISSN	1879-2707
出版年	2021
卷号	603
英文摘要	Hydrophobic soils, which form naturally in arid regions or after forest fires, can be problematic for land managers and engineers as they are often associated with impeded or preferential flow paths, increased surface runoff and soil erosion. However, the reduced rainwater infiltration capacity of water-repellent soils can also result in the improvement of the stability of slopes, landfills and capillary barrier cover systems, amongst others. Understanding the hydraulic conditions within these materials is critical if issues of stability and seepage are to become tractable. Traditional understanding of unsaturated hydrophobic soils suggests that convex water menisci, and so positive water pressures, should form between soil particles. However, the limited experimental results presented in the literature do not support this theory. In this work, the effect of particle shape on the formation and evolution of water meniscus structures is investigated at the macro (multiple particles) and particle scales, contrasting meniscus behaviours between spherical glass beads and angular sand grains. The spreading of a sessile drop in the macro-scale is examined and found that the angularity of the sand grains has a significant effect on the apparent contact angle of a sessile drop when deposited on a mono-layer of particles. At the particle scale, Environmental Scanning Electron Microscopy was used to investigate the formation and evolution of capillary bridges and the water retention hysteresis during two wetting and drying cycles. Again, it is shown that the shape and surface roughness of the particles are controlling factors in both the formation and evolution of liquid bridges and that stable convex and concave menisci can co-exist simultaneously between hydrophobic particle surfaces. Additionally, it was found that the hydrophobic nature of the particles allowed menisci to form across much larger separation distances than could be achieved through film coalescence between hydrophilic surfaces, with possible consequences for infiltration and imbibition modelling and, more broadly, manufacturing processes relying on hydrophobic substrates. Lastly, the hydrophobic soils qualitatively exhibited overall much less hysteresis of the water retention curve than their hydrophilic counterparts.
英文关键词	Hydrophobic sand and glass beads Capillary bridges Hysteresis ESEM Contact angle Goniometer
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000715326800002
WOS关键词	SOIL-WATER REPELLENCY ; CONTACT-ANGLE HYSTERESIS ; CAPILLARY BRIDGES ; ROUGH SPHERES ; LIQUID BRIDGE ; MODEL ; WETTABILITY ; RESISTANCE ; RETENTION ; WENZEL
WOS类目	Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources
WOS研究方向	Engineering ; Geology ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/368124
作者单位	[Karatza, Zeynep; Beckett, Christopher T. S.] Univ Edinburgh, Sch Engn, Inst Infrastruct & Environm, Edinburgh EH9 3JL, Midlothian, Scotland; [Buckman, Jim] Heriot Watt Univ, Inst Geoenergy Engn, EGIS, Edinburgh EH14 4AS, Midlothian, Scotland; [Medero, Gabriela M.] Heriot Watt Univ, Inst Infrastruct & Environm Energy Geosci Infrast, Edinburgh EH14 4AS, Midlothian, Scotland
推荐引用方式 GB/T 7714	Karatza, Zeynep,Buckman, Jim,Medero, Gabriela M.,et al. Evolution of meniscus structures in hydrophobic granular systems[J],2021,603.
APA	Karatza, Zeynep,Buckman, Jim,Medero, Gabriela M.,&Beckett, Christopher T. S..(2021).Evolution of meniscus structures in hydrophobic granular systems.JOURNAL OF HYDROLOGY,603.
MLA	Karatza, Zeynep,et al."Evolution of meniscus structures in hydrophobic granular systems".JOURNAL OF HYDROLOGY 603(2021).