Nonlocal transport models for capturing solute transport in one-dimensional sand columns: Model review, applicability, limitations and improvement

Zhang，Yong1; Zhou，Dongbao2; Yin，Maosheng3; Sun，Hong Guang2; Wei，Wei4; Li，Shiyin4; Zheng，Chunmiao5

2020

10.1002/hyp.13930

HYDROLOGICAL PROCESSES   影响因子和分区

0885-6087

1099-1085

Modelling pollutant transport in water is one of the core tasks of computational hydrology, and various physical models including especially the widely used nonlocal transport models have been developed and applied in the last three decades. No studies, however, have been conducted to systematically assess the applicability, limitations and improvement of these nonlocal transport models. To fill this knowledge gap, this study reviewed, tested and improved the state-of-the-art nonlocal transport models, including their physical background, mathematical formula and especially the capability to quantify conservative tracers moving in one-dimensional sand columns, which represents perhaps the simplest real-world application. Applications showed that, surprisingly, neither the popular time-nonlocal transport models (including the multi-rate mass transfer model, the continuous time random walk framework and the time fractional advection-dispersion equation), nor the spatiotemporally nonlocal transport model (ST-fADE) can accurately fit passive tracers moving through a 15-m-long heterogeneous sand column documented in literature, if a constant dispersion coefficient or dispersivity is used. This is because pollutant transport in heterogeneous media can be scale-dependent (represented by a dispersion coefficient or dispersivity increasing with spatiotemporal scales), non-Fickian (where plume variance increases nonlinearly in time) and/or pre-asymptotic (with transition between non-Fickian and Fickian transport). These different properties cannot be simultaneously and accurately modelled by any of the transport models reviewed by this study. To bypass this limitation, five possible corrections were proposed, and two of them were tested successfully, including a time fractional and space Hausdorff fractal model which minimizes the scale-dependency of the dispersion coefficient in the non-Euclidean space, and a two-region time fractional advection-dispersion equation which accounts for the spatial mixing of solute particles from different mobile domains. Therefore, more efforts are still needed to accurately model transport in non-ideal porous media, and the five model corrections proposed by this study may shed light on these indispensable modelling efforts.

non-Fickian dispersion nonlocal models sand column scale-dependent

SCI ; EI

英语

其他

National Natural Science Foundation of China[41931292] ; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control[2017B030301012]

Water Resources

Water Resources

WOS:000579735200001

WILEY

20204309383814

Continuous time systems ; One dimensional ; Solute transport ; Water pollution ; Mass transfer ; Sand ; Advection

Water Pollution:453 ; Soils and Soil Mechanics:483.1 ; Mass Transfer:641.3 ; Classical Physics; Quantum Theory; Relativity:931 ; Materials Science:951 ; Systems Science:961

ENVIRONMENT/ECOLOGY

2-s2.0-85092777276

Scopus

1.Department of Geological Sciences,University of Alabama,Tuscaloosa,United States
2.College of Mechanics and Materials,Hohai University,Nanjing,China
3.School of Environmental Studies,China University of Geosciences,Wuhan,China
4.School of Environment,Nanjing Normal University,Nanjing,China
5.School of Environmental Science & Engineering,Southern University of Science and Technology,Shenzhen,China

Zhang，Yong,Zhou，Dongbao,Yin，Maosheng,et al. Nonlocal transport models for capturing solute transport in one-dimensional sand columns: Model review, applicability, limitations and improvement[J]. HYDROLOGICAL PROCESSES,2020,34(25):5104-5122.

Zhang，Yong.,Zhou，Dongbao.,Yin，Maosheng.,Sun，Hong Guang.,Wei，Wei.,...&Zheng，Chunmiao.(2020).Nonlocal transport models for capturing solute transport in one-dimensional sand columns: Model review, applicability, limitations and improvement.HYDROLOGICAL PROCESSES,34(25),5104-5122.

Zhang，Yong,et al."Nonlocal transport models for capturing solute transport in one-dimensional sand columns: Model review, applicability, limitations and improvement".HYDROLOGICAL PROCESSES 34.25(2020):5104-5122.