Transp Porous Med
DOI 10.1007/s11242-017-0932-y
Exact Analytical Solution of the Telegraphic Warren
and Root Model
Alfredo González-Calderón
1
· Luis X. Vivas-Cruz
1
·
Uriel Salmerón-Rodríguez
1
Received: 9 March 2017 / Accepted: 18 September 2017
© Springer Science+Business Media B.V. 2017
Abstract We exactly solved a Warren and Root-like model that considers telegraphic fluid
flow, a constant hydraulic head at the bottomhole, and an infinite Euclidean reservoir with
radial flux. Complex integrals on the Bromwich contour are used to obtain the exact solutions
of the hydraulic head and flux. Given that the behavior of the propagation of the hydraulic
head has a discontinuous front, this system is appropriate for evaluating numerical methods
that have difficulties with discontinuities. To this end, the results from the Stehfest method
and Iseger method are analyzed.
Keywords Inversion Laplace transform · Telegraphic fluid flow · Double-porosity model
1 Introduction
Fluid flow through a porous medium is usually modeled using Darcy’s law. As a consequence
of this law, the partial differential equations (PDEs) used are diffusive type, i.e., parabolic type,
which implies that the disturbances in the pressure at the bottomhole are transmitted at infinite
velocity (Rehbinder 1989). With the goal of considering finite velocity pressure propagation,
Darcy’s law is modified in such a way that it looks similar to the Cattaneo equation (Cattaneo
1958). This extended formulation gives rise to hyperbolic PDEs, i.e., second-order wave-like
equations, which describe anomalous transport at short times Compte and Metzler (1997)
and ordinary diffusion at times greater than the relaxation time. It is noteworthy that these
hyperbolic models are usually known as telegraphic models. It has been observed that this
description has applications in petroleum engineering and groundwater sciences because
anomalous fluxes are associated with carbonate reservoirs (Wang 2013).
According to Economides and Nolte (2000), the equation for a single-phase radial flow at
the bottomhole of a single porosity medium “is perhaps the most important relationship in
B Alfredo González-Calderón
alfredo.gonzalez@cidesi.edu.mx
1
CONACyT - Centro de Ingeniería y Desarrollo Industrial (CIDESI), Av. Playa Pie de la cuesta 702,
Desarrollo San Pablo, 76125 Querétaro, QRO, Mexico
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