Page 172 - Percolation Models for Transport in Porous Media With
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10.1  CALCULATION                                                    169


            In this case the apparent resistance of the medium is
                                         00
                                 Ro(t) e:!  j[E(r,t)S (r)t dr               (10.8)
                                                       1
                                                  0
            Having divided  (10.2)  by  E(r, t)  and  after integrating with  respect  to r  from
         rw  to oo,  with regard to (10.8), we obtain

                        J(t) =  U  / Ro(t),  E(r, t) =  J(t)[E(r, t)S (r)t 1   {10.9)
                                                           0
            After adding the initial condition

                                        E(r, 0) =Eo                        {10.10)

         we obtain the following from  {10.9) - {10.10)
                             R{O)  =  Ro,  /(0) =  Io  = U/Ro,             (10.11)

                                                   0
                                     E(r,O) =  Io(EoS (r)t 1
            The expressions {10.7)- {10.11) represent a closed system of equations for the
         determination of the field  intensity distribution E(r, t), if the dependence of the
         specific electric conductivity on r  and t is known.
            To  determine  the change  in  the  well  production  after electric  treatment,  we
         will  use the equations of steady state flow  of an incompressible fluid  in  a  porous
         medium

                                         divv = 0,                        {10.12)
                                    v = -KJL-hilp                         {10.13)

         where v is the flow  velocity vector.
            Under the assumption the fluid flows at a constant depth, the initial and bound-
         ary conditions, have the following form

                       p(r, 0) =Po,  p(rw, t) =  Pw,  p(Raq, t) =Po,      {10.14)
                                      K(r, 0) = Ko(r)  e:!  K(Raq, t)

            Here,  as in  (10.1)  - {10.3),  the quasi-stationary nature of the process is  pro-
         posed, and therefore time tin (10.12) - (10.14) can be treated as a parameter.  In
         {10.14) Pw  is the pressure of the fluid  in  the well, Po  is the pressure at the supply
         line  Raq  ~>  rw,  where  the permeability  K 0  does  not  change and is  equal  to its
         initial value.  The initial layer pressure is also equal to Po·
            Since the well production
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