Sub-particle-scale investigation of seepage in sands

Autor: Simon J. Carr, Catherine O'Sullivan, Way Way Sim, H. F. Taylor
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Technology
CONSTRICTION SIZE
Water flow
POROUS-MEDIA
FLOW
IMAGES
0211 other engineering and technologies
02 engineering and technology
Computational fluid dynamics
Sands
010502 geochemistry & geophysics
PORE
Geological & Geomatics Engineering
01 natural sciences
Seepage
Permeability
0905 Civil Engineering
Physics::Geophysics
Hydraulic head
TORTUOSITY
0999 Other Engineering
Engineering
Hydraulic conductivity
Geotechnical engineering
Engineering
Geological

0503 Soil Sciences
Geosciences
Multidisciplinary

Z661
021101 geological & geomatics engineering
0105 earth and related environmental sciences
Civil and Structural Engineering
Permeameter
Science & Technology
SIZE DISTRIBUTIONS
business.industry
Geology
Geotechnical Engineering and Engineering Geology
Laboratory tests (IGC: D04/E13)
Volumetric flow rate
MODEL
Permeability (earth sciences)
Flow velocity
Numerical modelling
Physical Sciences
SIMULATION
business
ISSN: 0038-0806
Popis: While seepage poses significant challenges to many geotechnical projects and hydraulic conductivity is a key soil property, the fundamental pore-scale understanding of the water flow in soil is poor. The seepage velocities considered in geotechnical engineering are area-averaged flow rates and their relation to the actual fluid velocity is unclear. Some of the predictive formulae for sand currently used in engineering practice were developed using simplified particle-scale analytical models whose validity is not well-established. Recent advances in modelling and imaging enable these uncertainties associated with seepage to be addressed and this paper proposes a first principles simulation approach in which the flow in the void space is modelled by applying Computational Fluid Dynamics (CFD) to void geometries obtained using X-ray micro-Computed Tomography (microCT). The model was verified by comparing it to hydraulic conductivity data from laboratory permeameter tests on the same materials. The generated data provide significant sub-particle-scale insight into fluid velocities and head loss. The results are used to show that the existing models for predicting hydraulic conductivity struggle to account for the full range of particle variables and fail to explain the true governing variables, which relate to the micro-scale properties of the void space.
Databáze: OpenAIRE