Effect of wellbore storage and finite thickness skin on flow to a partially penetrating well in a phreatic aquifer

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

“…In general, the well skin can be classified into two types, the infinitesimal skin and finite thickness skin. The thickness of the well skin cannot be neglected (Novakowski 1989;Yang and Yeh 2007;Pasandi et al 2008;Yang et al 2014). In this case, the skin zone should be treated as a different formation zone with individual hydrodynamic properties and thickness.…”

“…In this case, the skin zone should be treated as a different formation zone with individual hydrodynamic properties and thickness. The flow to a constant-flux pumping well in an aquifer, considering finite thickness skin, has been extensively investigated (Yeh et al 2003;Perina and Lee 2006;Pasandi et al 2008;Chiu et al 2007). For instance, Yeh et al (2003) developed a closed-form analytical solution for a fully penetrating constant-flux pumping well in a two-zone confined aquifer.…”

Hydraulics of a partially penetrating well with skin zone in a confined aquifer

“…However, in some circumstances, a zone of higher conductivity (negative skin) in the immediate vicinity of a well as compared to regions farther away from the well may also develop due to extensive spalling and fracturing of the wellbore during drilling and/or due to extensive well development [29,30,39,[41][42][43][44]. The skin hydraulics problem for an aquifer of infinite horizontal dimension was solved analytically by several investigators [5,6,11,13,14,20,29,[31][32][33]39,[41][42][43][44] utilizing different assumptions. Whereas Novakowski [29], Yang and Yeh [39], Yeh et al [43], Cimen [14] and Yeh and Yang [44] provided analytical solutions to the problem by neglecting vertical flow, Novakowski [31] provided a solution by assigning a specified head on the well face but a zero head and not a zero flux in the non-active portion of the well, and Hyder et al [20], Yang and Yeh [41], Chiu et al [13], Yeh et al [42] and Chang et al [11] presented solutions by assuming a uniform radial flux at the well screen.…”

“…1 et al [6] in their analytical development. Pasandi et al [32] solved the skin hydraulics problem for a partially penetrating well in a phreatic aquifer but here also the well screen flux was assumed to be independent of the vertical ordinate, the aquifer to be of infinite horizontal extent and the bottom of the wellbore to not collect any water from the aquifer in the analysis. In this paper, we propose to develop a general steady state analytical solution to the partially penetrating well hydraulics problem for a confined aquifer with a finite skin by incorporating bottom flow as well as finite horizontal and vertical extent of the aquifer into the solution.…”

Transient solution for radial two‐zone flow in unconfined aquifers under constant‐head tests

“…They took a non-uniform radial flux along the screen and a finite-thickness well skin into account. Pasandi et al (2008) presented an analytical solution for CRT conducted in a partially penetrating well in an unconfined aquifer. A finite thickness of well skin is considered in their solution and the influence of the skin is also investigated.…”