Page 217 - Reservoir Formation Damage
P. 217
198 Reservoir Formation Damage
Substituting Eqs. 10-66 and 67, and rearranging Eq. 10-65 becomes:
(10-68)
subject to the initial condition given by:
•
= 4UW = 1, 2, •-, n, t = 0 (10-69)
(<!>Pp/) y
and the boundary condition given by:
(10-70)
The mass balance of particles captured at the pore throats is given by:
dm p /dt = r r (10-71)
subject to
= 0, t = 0 (10-72)
m p
The mass balance of indigeneous particles remaining on pore surfaces is
dm* p/dt = -r e (10-73)
subject to
rn p=m po,t = (10-74)
where m po is the mass of particles initially available on pore surface.
The rate of particle entrainment by the flowing phase is assumed both
colloidally and hydrodynamically induced.
r=oc m l +oc, |T — T Ifl (10-75)
T
e c ' p h V c ) s
T is shear stress. a s is the specific pore surface area. <*£, is the colloidally
induced release coefficient given by (Khilar and Fogler, 1983):
(10-76)