Water and Air Redistribution within a Dual Permeability Porous System Investigated Using Neutron Imaging

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F15%3A00230815" target="_blank" >RIV/68407700:21110/15:00230815 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21720/15:00230815

Výsledek na webu

<a href="http://www.sciencedirect.com/science/article/pii/S1875389215006859" target="_blank" >http://www.sciencedirect.com/science/article/pii/S1875389215006859</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.phpro.2015.07.075" target="_blank" >10.1016/j.phpro.2015.07.075</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Water and Air Redistribution within a Dual Permeability Porous System Investigated Using Neutron Imaging

Popis výsledku v původním jazyce

A ponded infiltration experiment was conducted under simultaneous imaging to investigate variations in quasi-saturated hydraulic conductivity a process frequently observed in infiltration experiments in soils with wide grain - size distribution. An artificially prepared heterogeneous sample composed of coarse quartz sand (representing pathways of preferential flow) and fine porous ceramic (representing soil matrix) was investigated. The sample was 34.5 mm high and 29.0 mm in diameter. Sequences of neutron radiography images (RI) of pixel size 0.045 x 0.045 mm were taken at one angle during particular transient phases of the flow process. During quasi-steady state flow stages of the experiment radiography images were acquired in range of angles 0-180° in 0.9° step and. 3D neutron tomograms (TI) were then developed. Using the data a quantitative evaluation of the spatial and temporal distribution of water content within the sample was conducted. For every RI and TI the amount of water in particular pixels and voxels, respectively, was calculated by subtracting the image of dry sample. The accuracy of the water content estimates derived from the images was checked by comparing them to the corresponding gravimetrically determined water content data. Heavy water with equilibrium air saturation was introduced into the sample during two recurrent infiltrations. Thirty five hours later, during second infiltration, the inflow was switched to degassed heavy water in order to remove residual air present in the sample. During the first twelve hours of first infiltration run flow rate through the sample decreased from 3.7 cm/hour to 1.0 cm/hour at the end of the “steady state flow” stage. The flow rate in second run decreased from 3.6 cm/hour to 1.6 cm/hour. Comparison of the tomogram of the sample at the beginning and one taken at the end of the steady state flow stage in each run shows an increase of water content in the porous ceramic.

Název v anglickém jazyce

Water and Air Redistribution within a Dual Permeability Porous System Investigated Using Neutron Imaging

Popis výsledku anglicky

A ponded infiltration experiment was conducted under simultaneous imaging to investigate variations in quasi-saturated hydraulic conductivity a process frequently observed in infiltration experiments in soils with wide grain - size distribution. An artificially prepared heterogeneous sample composed of coarse quartz sand (representing pathways of preferential flow) and fine porous ceramic (representing soil matrix) was investigated. The sample was 34.5 mm high and 29.0 mm in diameter. Sequences of neutron radiography images (RI) of pixel size 0.045 x 0.045 mm were taken at one angle during particular transient phases of the flow process. During quasi-steady state flow stages of the experiment radiography images were acquired in range of angles 0-180° in 0.9° step and. 3D neutron tomograms (TI) were then developed. Using the data a quantitative evaluation of the spatial and temporal distribution of water content within the sample was conducted. For every RI and TI the amount of water in particular pixels and voxels, respectively, was calculated by subtracting the image of dry sample. The accuracy of the water content estimates derived from the images was checked by comparing them to the corresponding gravimetrically determined water content data. Heavy water with equilibrium air saturation was introduced into the sample during two recurrent infiltrations. Thirty five hours later, during second infiltration, the inflow was switched to degassed heavy water in order to remove residual air present in the sample. During the first twelve hours of first infiltration run flow rate through the sample decreased from 3.7 cm/hour to 1.0 cm/hour at the end of the “steady state flow” stage. The flow rate in second run decreased from 3.6 cm/hour to 1.6 cm/hour. Comparison of the tomogram of the sample at the beginning and one taken at the end of the steady state flow stage in each run shows an increase of water content in the porous ceramic.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20101 - Civil engineering

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2015

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Physics Procedia

ISBN

—

ISSN

1875-3892

e-ISSN

1875-3892

Počet stran výsledku

7

Strana od-do

530-536

Název nakladatele

Elsevier

Místo vydání

Amsterdam

Místo konání akce

Grindelwald

Datum konání akce

5. 10. 2014

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000380606800075