1 research outputs found
Flow Behavior Characterization of a Polyacrylamide-Based Friction Reducer in Microchannels
Horizontal well and hydraulic fracturing
have been proven to be
effective technologies for increasing the recovery of shale gas reservoirs.
During a fracturing treatment, a pair of main fractures is first generated
perpendicular to the wellbore direction. As fluids continue to be
pumped, more microsized fractures are generated near the main fractures
and form a fracture network. This micrometer-sized fracture network
has much more contact area with the matrix than a traditional single
pair of fractures and holds the majority of the productivity potential
of shale gas. Friction reducer (FR) is one of the primary components
of this fracturing fluid. It is used to decrease the flowing friction
in pipeline. Flow loop tests in lab and field applications have addressed
this issue thoroughly. However, the flow characteristics of friction
reducer solutions in microfractures are not clear. This study used
capillary tubes to represent microchannels, and the flow behavior
of FR solutions in these microchannels was systematically studied.
With FR solution flowing in the microchannels at various velocities,
the impact of different FR concentrations, microchannel sizes, and
microchannel surface wettability on the FR flow behavior was investigated
in detail. It is found that the friction reducer is a slight shear-thinning
fluid with properties that can be expressed by a power-law equation.
Its residual resistance factor to water was also specified, which
is closely related with the fluid flowback. Finally, the experimental
results were compared with the data in a flow loop experiment. Its
flow resistance was found to be increased in microchannels rather
than decreased as was observed in the centimeter-sized tubing