Page 174 - Percolation Models for Transport in Porous Media With

10.2 OPTIMAL TREATMENT REGIME 171

I
J

2
2

!'

2 4 !gt/t.
Figure 64: Relation for the irreversible change of well production when it is
treated with alternating (1', 2') and impulse (1, 2} current

In fig. 64, the dependencies of the well production change for a homogeneous
and a heterogeneous media are presented. The parameters of these dependencies
are the same as in §8.2, 8.4. Calculations involving /(r) of the form (8.19} with
i = 1, j = 2 and i = 5, j = 10 correspond to the numbers 1, 2, respectively.
Duration of the electric treatment is plotted on the x-axis and is uniquely
related to the total energy consumption

t
We= U 2 J dt/Ro(t)
0
Here to is the time for the input of an energy unit Weo, for example, of 1 kilojoule.

10.2 Reversible Change of Permeability. Deter-

mination of Optimal Regime for Electric
Treatment

In chapter 9, it was shown how the dependence of the effective permeability on the
amount of electric energy put in the medium (or on the current density and the du-
ration of treatment) can be determined using the data of a laboratory experiment.
If the heat capacity and the density of the medium are known, these dependencies
can be transformed into a temperature dependence of the permeability.
Consider the problem of steady state flow of a conducting fluid in a micro-
heteroeneous medium as current I passes through it, and the increase of the per-
meability is reversible.
Suppose that the fluid is recovered from a well with radius rw, kept at the
constant pressure Pw· Let the regions of current and fluid flow coincide and be