Page 326 - Intelligent Digital Oil And Gas Fields

Smart Wells and Techniques for Reservoir Monitoring 271

μ o, μ w , and μ g are the oil, water, and gas viscosities at pressure and temper-
ature in cP,
water.vol, oil.vol, and gas.vol are the volume fractions of the phases in the
wellbore at time t,
X is the device strength parameter, which is measured during the calibration
3
3
process in psi/(lb/ft ft ),
β is the viscosity exponent measured during the calibration in the lab
(dimensionless), and
α is the rate-dependent exponent measured during the calibration in the lab
(dimensionless).
Carvajal and Torres (2014) have shown the impact of an AICD comple-
tion coupled with a 3D-gridded, three-phase flow numerical model applied
in a horizontal well with three different oil viscosities: 1, 10, and 100cP.
They found that an AICD does not have a significant impact on the produc-
tion for those cases with oil viscosity below 1cP or viscosity close to water
viscosity. However, they found that in a scenario with a viscosity ratio two
times more than water viscosity, the AICD had a significant impact on oil
recovery. They simulated one horizontal well producer of 5000ft with an
injector horizontal well in a reservoir of 10cP oil viscosity and permeability
variation between 1 and 100 md. The model was set up with 40 AICDs (a
grid block per AICD, grid block size¼20ft). The simulation results are
shown in Fig. 7.15 comparing an open-hole completion with an AICD
and a full producer completion with an AICD.
The producer well and the injector are separated by a distance of 3km.
The water breaks through the producer at 380days after the first water injec-
tion. In both cases, the water breakthrough time is the same; water arrived at
the middle of the lateral. Therefore, the AICD does not contribute signif-
icantly in delaying the water breakthrough. However, before day 1500 of
production, using streamline simulation, the water is deviated and bypassed
the wellbore, whereas oil was directly injected into the wellbore, following
exactly the same physics principles of kinematic differences between fluids
(ρ o .μ w /ρ w .μ o ).
Finally, they found that using AICDs, the oil-recovery factor was
increased by 20%, and water is significantly reduced from 60% to 20%, com-
pared with an open-hole completion. More than 20% increment was
observed after water breakthrough. The AICD had a significant impact
on controlling water after water breakthrough. Nevertheless, we believe
that the best combination is to set up both an ICD and an AICD, which
could reduce the water breakthrough time.