On the aquitard–aquifer interface flow and the drawdown sensitivity with a partially penetrating pumping well in an anisotropic leaky confined aquifer

Feng, Qilin; Zhan, Hongbin

doi:10.1016/j.jhydrol.2014.11.058

Cited by 32 publications

(16 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Malama et al (2008) derived a semi-analytical solution for flow toward a partially penetrating well pumped at a constant rate in a leaky unconfined aquifer. Feng and Zhan (2015) derived a semi-analytical solution for flow toward a partially penetrating well pumped at a constant rate in a leaky confined aquifer. Most of the previous studies about groundwater flow to a partially penetrating well are based on the flow being Darcian.…”

Section: Introductionmentioning

confidence: 99%

Non-Darcian flow to a partially penetrating well in a confined aquifer with a finite-thickness skin

Feng

Wen

2016

Hydrogeol J

Self Cite

View full text Add to dashboard Cite

Non-Darcian flow to a partially penetrating well in a confined aquifer with a finite-thickness skin was investigated. The Izbash equation is used to describe the non-Darcian flow in the horizontal direction, and the vertical flow is described as Darcian. The solution for the newly developed nonDarcian flow model can be obtained by applying the linearization procedure in conjunction with the Laplace transform and the finite Fourier cosine transform. The flow model combines the effects of the non-Darcian flow, partial penetration of the well, and the finite thickness of the well skin. The results show that the depression cone spread is larger for the Darcian flow than for the non-Darcian flow. The drawdowns within the skin zone for a fully penetrating well are smaller than those for the partially penetrating well. The skin type and skin thickness have great impact on the drawdown in the skin zone, while they have little influence on drawdown in the formation zone. The sensitivity analysis indicates that the drawdown in the formation zone is sensitive to the power index (n), the length of well screen (w), the apparent radial hydraulic conductivity of the formation zone (K r2 ), and the specific storage of the formation zone (S s2 ) at early times, and it is very sensitive to the parameters n, w and K r2 at late times, especially to n, while it is not sensitive to the skin thickness (r s ).

show abstract

Section: Introductionmentioning

confidence: 99%

Non-Darcian flow to a partially penetrating well in a confined aquifer with a finite-thickness skin

Feng

Wen

2016

Hydrogeol J

Self Cite

View full text Add to dashboard Cite

show abstract

“…Neuman [44,45] developed solutions considering both confined storage and delayed yield from the unconfined aquifer. A variety of new analytical approaches were applied to deal with well hydraulics models involving mixed and complicated boundaries, which gained more accurate solutions for particular conditions [7,36,39,[46][47][48][49][50][51]. Mishra and Kuhlman [52] have recently summarized the application of the Dupuit theory for an unconfined aquifer from Dupuit to the present.…”

Section: Dupuit and Dupuit-thiem Formulaementioning

confidence: 99%

Seepage Characteristics of a Single Ascending Relief Well Dewatering an Overlying Aquifer

Wang

Faybishenko

Jiang

et al. 2020

Water

View full text Add to dashboard Cite

The application of groundwater relief, i.e., dewatering, ascending wells, drilled upward from the mining tunnel into the overlying aquifer, is common in underground mining engineering. In this study, the seepage characteristics of single ascending partially and fully penetrating relief wells are investigated using a series of laboratory sand-tank experiments and numerical simulations. The seepage characteristics of ascending wells dewatering an overlying aquifer are different from those of conventional pumping wells descending from the ground surface into the underlying aquifer, because of the pronounced influence of the seepage face boundary condition along the seepage boundary of the ascending dewatering well. The seepage face of the ascending well is formed as the well casing remains open and water is discharged under the action of gravity through the well casing. The results of laboratory sand-tank experiments and modeling show that when the degree of penetration of an ascending relief well does not exceed a critical value, the effect of the seepage face cannot be ignored. In particular, the seepage flux increases as the degree of penetration increases following an exponential function, and the relationship between the seepage flux and the well radius can be described using a power law function. The results of numerical simulations are used to develop a series of type curves to evaluate the effects of the critical degree of penetration for different well radii and different aquifer water levels. Modified versions of the Dupuit and Dupuit–Thiem formulae for a single ascending partially well for the degree of penetration less than the critical one for the unconfined, confined, and confined-unconfined aquifers are developed.

show abstract

“…(2020), Feng et al (2019Feng et al ( , 2020, Feng and Zhan (2015, 2016, Hantush (1960Hantush ( , 1964,  Hemker and Maas (1987), Hunt (2005), Moehch (1985, Neuman and Witherspoon (1969),  Sepúlveda (2008), Wang et al (2015) and Wen et al (2011Wen et al ( , 2013…”

Section: mentioning

confidence: 99%

Three-dimensional transient flow to a partially penetrated well with variable discharge in a general three-layer aquifer system

Feng

2020

Preprint

Self Cite

View full text Add to dashboard Cite

Abstract. A general analytical model for three-dimensional flow in a three-layered aquifer system with a partial penetration well having a variable discharge of pumping is developed by taking account of the interface flow on the adjacent layers. This general three-layer system includes the conventional aquitard-aquifer-aquitard system as a subset and does not require that the permeability contrasts of different layers must be greater than a few orders of magnitude, and does not ignore any flow components (either vertical or horizontal) in any particular layer. The pumping well of infinitesimal radius is screened at any portion of the middle layer. Three widely used top and bottom boundary conditions are considered that can be specified as a constant-head boundary (Case1) or a no-flux boundary (Case 2), and a constant-head boundary at the top in combination with a no-flux boundary at the bottom (Case 3). Laplace domain solutions for dimensionless drawdown are obtained by the use of Hankel transformation, and associated time-domain solutions are evaluated numerically. The newly obtained solutions include some available solutions for two- or single-layer aquifer systems as subsets. The drawdowns for individual layers caused by a well with an exponentially decreased discharge are explored as an example of illustration. The results indicate that the pumped layer drawdown close to the partially penetrated well is mainly influenced by the variable pumping rate. The late-time drawdowns for all layers are remarkably affected by the chosen types of top and bottom boundary conditions, and the drawdown for Case 3 is greater than that for Case 1 and smaller than that for Case 2. Additionally, the effect of the pumped layer anisotropy on drawdowns in the three-layer system is significant, and the anisotropy of the unpumped layers significantly affects the drawdown in the whole aquifer system without large contrast of hydraulic conductivity between the unpumped layers and the pumped layer. The drawdowns in all three layers are greatly affected by the location and length of well screen, and a larger drawdown can be seen at the position that is closer to the middle point of the screen of the partially penetrating pumping well.

show abstract

On the aquitard–aquifer interface flow and the drawdown sensitivity with a partially penetrating pumping well in an anisotropic leaky confined aquifer

Cited by 32 publications

References 51 publications

Non-Darcian flow to a partially penetrating well in a confined aquifer with a finite-thickness skin

Non-Darcian flow to a partially penetrating well in a confined aquifer with a finite-thickness skin

Seepage Characteristics of a Single Ascending Relief Well Dewatering an Overlying Aquifer

Three-dimensional transient flow to a partially penetrated well with variable discharge in a general three-layer aquifer system

Contact Info

Product

Resources

About