BIDIRECTIONAL DOWNHOLE FLUID FLOW CONTROL
SYSTEM AND METHOD
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates, in general, to equipment utilized in conjunction with
operations performed in subterranean wells and, in particular, to a downhole fluid flow
control system and method that are operable to control the inflow of formation fluids and the
outflow of injection fluids.
BACKGROUND OF THE INVENTION
[0002] Without limiting the scope of the present invention, its background will be
described with reference to steam injection into a hydrocarbon bearing subterranean
formation, as an example.
[0003] During the production of heavy oil, oil with high viscosity and high specific
gravity, it is sometimes desirable to inject a recovery enhancement fluid into the reservoir to
improve oil mobility. One type of recovery enhancement fluid is steam that may be injected
using a cyclic steam injection process, which is commonly referred to as a "huff and puff
operation. In such a cyclic steam stimulation operation, a well is put through cycles of steam
injection, soak and oil production. In the first stage, high temperature steam is injected into
the reservoir. In the second stage, the well is shut to allow for heat distribution in the
reservoir to thin the oil. During the third stage, the thinned oil is produced into the well and
may be pumped to the surface. This process may be repeated as required during the
productive lifespan of the well.
[0004] In wells having multiple zones, due to differences in the pressure and/or
permeability of the zones as well as pressure and thermal losses in the tubular string, the
amount of steam entering each zone may be difficult to control. One way to assure the
desired steam injection at each zone is to establish a critical flow regime through nozzles
associated with each zone. Critical flow of a compressible fluid through a nozzle is achieved
when the velocity through the throat of the nozzle is equal to the sound speed of the fluid at
local fluid conditions. Once sonic velocity is reached, the velocity and therefore the flow rate
of the fluid through the nozzle cannot increase regardless of changes in downstream
conditions. Accordingly, regardless of the differences in annular pressure at each zone, as
long as critical flow is maintained at each nozzle, the amount of steam entering each zone is
known.
[0005] It has been found, however, that achieving the desired injection flowrate and
pressure profile by reverse flow through conventional flow control devices is impracticable.
As the flow control components are designed for production flowrates, attempting to reverse
flow through conventional flow control components at injection flowrates causes an
unacceptable pressure drop. Accordingly, a need has arisen for a fluid flow control system
that is operable to control the inflow of fluids for production from the formation. A need has
also arisen for such a fluid flow control system that is operable to control the outflow of
fluids from the completion string into the formation at the desired injection flowrate. Further,
a need has arisen for such a fluid flow control system that is operable to allow repeated cycles
of inflow of formation fluids and outflow of injection fluids.
SUMMARY OF THE INVENTION
[0006] The present invention disclosed herein comprises a downhole fluid flow control
system and method for controlling the inflow of fluids for production from the formation. In
addition, the downhole fluid flow control system and method of the present invention are
operable to control the outflow of fluids from the completion string into the formation at the
desired injection flowrate. Further, the downhole fluid flow control system and method of
the present invention are operable to allow repeated cycles of inflow of formation fluids and
outflow of injection fluids.
[0007] In one aspect, the present invention is directed to a bidirectional downhole fluid
flow control system. The system includes at least one injection flow control component and
at least one production flow control component, in parallel with the at least one injection flow
control component. The at least one injection flow control component and the at least one
production flow control component each have direction dependent flow resistance such that
injection fluid flow experiences a greater flow resistance through the at least one production
flow control component than through the at least one injection flow control component and
such that production fluid flow experiences a greater flow resistance through the at least one
injection flow control component than through the at least one production flow control
component.
[0008] In one embodiment, the at least one injection flow control component may be a
fluidic diode providing greater resistance to flow in the production direction than in the
injection direction. In this embodiment, the fluidic diode may be a vortex diode wherein
injection fluid flow entering the vortex diode travels primarily in a radial direction and
wherein production fluid flow entering the vortex diode travels primarily in a tangential
direction. In another embodiment, the at least one production flow control component may
be a fluidic diode providing greater resistance to flow in the injection direction than in the
production direction. In this embodiment, the fluidic diode may be a vortex diode wherein
production fluid flow entering the vortex diode travels primarily in a radial direction and
wherein injection fluid flow entering the vortex diode travels primarily in a tangential
direction.
[0009] In one embodiment, the at least one injection flow control component may be a
fluidic diode providing greater resistance to flow in the production direction than in the
injection direction in series with a nozzle having a throat portion and a diffuser portion
operable to enable critical flow therethrough. In other embodiments, the at least one injection
flow control component may be a fluidic diode providing greater resistance to flow in the
production direction than in the injection direction in series with a fluid selector valve. In
certain embodiments, the at least one production flow control component may be a fluidic
diode providing greater resistance to flow in the injection direction than in the production
direction in series with an inflow control device.
[0010] In another aspect, the present invention is directed to a bidirectional downhole
fluid flow control system. The system includes at least one injection vortex diode and at least
one production vortex diode. In this configuration, injection fluid flow entering the injection
vortex diode travels primarily in a radial direction while production fluid flow entering the
injection vortex diode travels primarily in a tangential direction. Likewise, production fluid
flow entering the production vortex diode travels primarily in a radial direction while
injection fluid flow entering the production vortex diode travels primarily in a tangential
direction.
[0011] In one embodiment, the at least one injection vortex diode may be in series with a
nozzle having a throat portion and a diffuser portion operable to enable critical flow
therethrough. In another embodiment, the at least one injection vortex diode may be in series
with a fluid selector valve. In a further embodiment, the at least one production vortex diode
may be in series with an inflow control device. In certain embodiments, the at least one
injection vortex diode may be a plurality of injection vortex diodes in parallel with each
other. In other embodiments, the at least one production vortex diode may be a plurality of
production vortex diodes in parallel with each other.
[0012] In a further aspect, the present invention is directed to a bidirectional downhole
fluid flow control method. The method includes providing a fluid flow control system at a
target location downhole, the fluid flow control system having at least one injection flow
control component and at least one production flow control component in parallel with the at
least one injection flow control component; pumping an injection fluid from the surface into a
formation through the fluid flow control system such that the injection fluid experiencing
greater flow resistance through the production flow control component than through the
injection flow control component; and producing a formation fluid to the surface through the
fluid flow control system such that the production fluid experiencing greater flow resistance
through the injection flow control component than through the production flow control
component. The method may also include pumping the injection fluid through parallel
opposing fluid diodes, each having direction dependent flow resistance, producing the
formation fluid through parallel opposing fluid diodes, each having direction dependent flow
resistance, pumping the injection fluid through parallel opposing vortex diodes, each having
direction dependent flow resistance, producing the formation fluid through parallel opposing
vortex diodes, each having direction dependent flow resistance or pumping the injection fluid
through an injection fluid diode having direction dependent flow resistance and a nozzle in
series with the fluid diode, the nozzle having a throat portion and a diffuser portion operable
to enable critical flow therethrough.
A bidirectional downhole fluid flow control system comprising:
[0013] In an additional aspect, the present invention is directed to a bidirectional
downhole fluid flow control system. The system includes at least one injection flow control
component and at least one production flow control component, in parallel with the at least
one injection flow control component. The at least one injection flow control component has
direction dependent flow resistance such that inflow of production fluid experiences a greater
flow resistance through the at least one injection flow control component than outflow of
injection fluid through the at least one injection flow control component.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of the features and advantages of the present
invention, reference is now made to the detailed description of the invention along with the
accompanying figures in which corresponding numerals in the different figures refer to
corresponding parts and in which:
[0015] Figure 1 is a schematic illustration of a well system operating a plurality of
downhole fluid flow control systems according to an embodiment of the present invention
during an injection phase of well operations;
[0016] Figure 2 is a schematic illustration of a well system operating a plurality of
downhole fluid flow control systems according to an embodiment of the present invention
during a production phase of well operations;
[0017] Figures 3A-3B are schematic illustrations of flow control components having
directional dependent flow resistance for use in a fluid flow control system according to an
embodiment of the present invention;
[0018] Figures 4A-4B are schematic illustrations of flow control components having
directional dependent flow resistance for use in a fluid flow control system according to an
embodiment of the present invention;
[0019] Figures 5A-5B are schematic illustrations of flow control components having
directional dependent flow resistance for use in a fluid flow control system according to an
embodiment of the present invention;
[0020] Figures 6A-6B are schematic illustrations of a two stage flow control component
having two flow control elements in series and having directional dependent flow resistance
for use in a fluid flow control system according to an embodiment of the present invention;
[0021] Figures 7A-7B are schematic illustrations of a two stage flow control component
having two flow control elements in series and having directional dependent flow resistance
for use in a fluid flow control system according to an embodiment of the present invention;
[0022] Figure 8 is a schematic illustration of a two stage flow control component having
two flow control elements in series and having directional dependent flow resistance for use
in a fluid flow control system according to an embodiment of the present invention;
[0023] Figure 9 is a schematic illustration of a two stage flow control component having
two flow control elements in series and having directional dependent flow resistance for use
in a fluid flow control system according to an embodiment of the present invention;
[0024] Figures 10A-10B are schematic illustrations of two stage flow control components
having directional dependent flow resistance for use in a fluid flow control system according
to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] While the making and using of various embodiments of the present invention are
discussed in detail below, it should be appreciated that the present invention provides many
applicable inventive concepts which can be embodied in a wide variety of specific contexts.
The specific embodiments discussed herein are merely illustrative of specific ways to make
and use the invention, and do not delimit the scope of the present invention.
[0026] Referring initially to figure 1, a well system including a plurality of bidirectional
downhole fluid flow control systems positioned in a downhole tubular string is schematically
illustrated and generally designated 10. A wellbore 1 extends through the various earth
strata including formations 14, 16, 18. Wellbore 12 includes casing 20 that may be cemented
within wellbore 12. Casing 20 is perforated at each zone of interest corresponding to
formations 14, 16, 18 at perforations 22, 24, 26. Disposed with casing 20 and forming a
generally annular area therewith is a tubing string 28 that includes a plurality of tools such as
packers 30, 32 that isolate annulus 34, packers 36, 38 that isolate annulus 40 and packers 42,
44 that isolate annulus 46. Tubing string 28 also includes a plurality of bidirectional
downhole fluid flow control systems 48, 50, 52 that are respectively positioned relative to
annuluses 34, 40, 46. Tubing string 28 defines a central passageway 54.
[0027] In the illustrated embodiment, fluid flow control system 48 has a plurality of
injection flow control components 56, fluid flow control system 50 has a plurality of injection
flow control components 58 and fluid flow control system 52 has a plurality of injection flow
control components 60. In addition, fluid flow control system 48 has a plurality of
production flow control components 62, fluid flow control system 50 has a plurality of
production flow control components 64 and fluid flow control system 52 has a plurality of
production flow control components 66. Flow control components 56, 62 provide a plurality
of flow paths between central passageway 54 and annulus 34 that are in parallel with one
another. Flow control components 58, 64 provide a plurality of flow paths between central
passageway 54 and annulus 40 that are in parallel with one another. Flow control
components 60, 66 provide a plurality of flow paths between central passageway 54 and
annulus 46 that are in parallel with one another. Each of flow control components 56, 58, 60,
62, 64, 66 includes at least one flow control element, such as a fluid diode, having direction
dependent flow resistance.
[0028] In this configuration, each fluid flow control system 48, 50, 52 may be used to
control the injection rate of a fluid into its corresponding formation 14, 16, 18 and the
production rate of fluids from its corresponding formation 14, 16, 18. For example, during a
cyclic steam stimulation operation, steam may be injected into formations 14, 16, 18 as
indicated by arrows 68 in central passageway 54, large arrows 70 and small arrows 72 in
annulus 34, large arrows 74 and small arrows 76 in annulus 40, and large arrows 78 and small
arrows 80 in annulus 46, as best seen in figure 1. When the steam injection phase of the
cyclic steam stimulation operation is complete, well system 10 may be shut in to allow for
heat distribution in formations 14, 16, 18 to thin the oil. After the soaking phase of the cyclic
steam stimulation operation, well system 10 may be opened to allow reservoir fluids to be
produced into the well from formations 14, 16, 18 as indicated by arrows 82 in central
passageway 54, arrows 84 in annulus 34, large arrows 86 and small arrows 88 in fluid flow
control system 48, arrows 90 in annulus 40, large arrows 92 and small arrows 94 in fluid flow
control system 50 and arrows 96 in annulus 46, large arrows 98 and small arrows 100 in fluid
flow control system 52, as best seen in figure 2. After the production phase of the cyclic
steam stimulation operation, the phases of the cyclic steam stimulation operation may be
repeated as necessary.
[0029] As stated above, each of flow control components 56, 58, 60, 62, 64, 66 includes
at least one flow control element having direction dependent flow resistance. This direction
dependent flow resistance determines the volume or relative volume of fluid that is capable of
flowing through a particular flow control component. In the fluid injection operation
depicted in figure 1, the relative fluid injection volumes are indicated as large arrows 70, 74,
78 representing injection through flow control components 56, 58, 60, respectively and small
arrows 72, 76, 80 representing injection through flow control components 62, 64, 66,
respectively. Likewise, in the fluid production operation depicted in figure 2, the relative
fluid production volumes are indicated as large arrows 86, 92, 98 representing production
through flow control components 62, 64, 66, respectively and small arrows 88, 94, 100
representing production through flow control components 56, 58, 60, respectively. In the
illustrated embodiment, injection fluid flow experiences a greater flow resistance through
flow control components 62, 64, 66 than through flow control components 56, 58, 60 while
production fluid flow experiences a greater flow resistance through flow control components
56, 58, 60 than through flow control components 62, 64, 66. In this configuration, flow
control components 62, 64, 66 may be referred to as production flow control components as a
majority of the production flow passes therethrough and flow control components 56, 58, 60
may be referred to as injection flow control components as a majority of the injection flow
passes therethrough.
[0030] Even though figures 1 and 2 depict the present invention in a vertical section of
the wellbore, it should be understood by those skilled in the art that the present invention is
equally well suited for use in wells having other directional configurations including
horizontal wells, deviated wells, slanted wells, multilateral wells and the like. Accordingly, it
should be understood by those skilled in the art that the use of directional terms such as
above, below, upper, lower, upward, downward, left, right, uphole, downhole and the like are
used in relation to the illustrative embodiments as they are depicted in the figures, the upward
direction being toward the top of the corresponding figure and the downward direction being
toward the bottom of the corresponding figure, the uphole direction being toward the surface
of the well and the downhole direction being toward the toe of the well. Also, even though
figures 1 and 2 depict a particular number of fluid flow control systems with each zone, it
should be understood by those skilled in the art that any number of fluid flow control systems
may be associated with each zone including having different numbers of fluid flow control
systems associated with different zones. Further, even though figures 1 and 2 depict the fluid
flow control systems as having flow control capabilities, it should be understood by those
skilled in the art that fluid flow control systems could have additional capabilities such as
sand control. In addition, even though figures 1 and 2 depict the fluid flow control systems
as having a particular configuration of production flow control components and injection
flow control components, it should be understood by those skilled in the art that fluid flow
control systems having other configurations of production flow control components and
injection flow control components are possible and are considered within the scope of the
present invention. For example, the production flow control components may be positioned
uphole of the injection flow control components. There may be a greater or lesser number of
production flow control components than injection flow control components. Certain or all
of the production flow control components may be positioned about the same circumferential
location as certain or all of the injection flow control components. Some of the production
flow control components may be positioned about a different circumferential location than
other of the production flow components. Likewise, some of the injection flow control
components may be positioned about a different circumferential location than other of the
injection flow components.
[0031] Referring next to figures 3A-3B, therein is depicted a portion of a fluid flow
control system having flow control components with directional dependent flow resistance,
during injection and production operations, respectively, that is generally designated 110. In
the illustrated section, two opposing flow control components 112, 114 are depicted wherein
flow control component 112 is an injection flow control component and flow control
component 114 is a production flow control component. As illustrated, flow control
component 112 is a fluid diode in the form of a vortex diode having a central port 116, a
vortex chamber 118 and a lateral port 120. Likewise, flow control component 114 is a fluid
diode in the form of a vortex diode having a central port 122, a vortex chamber 124 and a
lateral port 126.
[0032] Figure 3A represents an injection phase of well operations. Injection flow is
depicted as arrows 128 in flow control component 112 and as arrows 130 in flow control
component 114. As illustrated, injection fluid 130 entering flow control component 114 at
lateral port 126 is directed into vortex chamber 124 primarily in a tangentially direction
which causes the fluid to spiral around vortex chamber 124, as indicted by the arrows, before
eventually exiting through central port 122. Fluid spiraling around vortex chamber 124
suffers from frictional losses. Further, the tangential velocity produces centrifugal force that
impedes radial flow. Consequently, injection fluid passing through flow control component
114 that enters vortex chamber 124 primarily tangentially encounters significant resistance
which results in a significant reduction in the injection flowrate therethrough.
[0033] At the same time, injection fluid 128 entering vortex chamber 118 from central
port 116 primarily travels in a radial direction within vortex chamber 118, as indicted by the
arrows, before exiting through lateral port 120 with little spiraling within vortex chamber 116
and without experiencing the associated frictional and centrifugal losses. Consequently,
injection fluid passing through flow control component 112 that enters vortex chamber 118
primarily radially encounters little resistance and passes therethrough relatively unimpeded
enabling a much higher injection flowrate as compared to the injection flowrate through flow
control component 114.
[0034] Figure 3B represents a production phase of well operations. Production flow is
depicted as arrows 132 in flow control component 112 and as arrows 134 in flow control
component 114. As illustrated, production fluid 132 entering flow control component 112 at
lateral port 120 is directed into vortex chamber 118 primarily in a tangentially direction
which causes the fluid to spiral around vortex chamber 118, as indicted by the arrows, before
eventually exiting through central port 116. Fluid spiraling around vortex chamber 118
suffers from frictional and centrifugal losses. Consequently, production fluid passing through
flow control component 112 that enters vortex chamber 118 primarily tangentially encounters
significant resistance which results in a significant reduction in the production flowrate
therethrough.
[0035] At the same time, production fluid 134 entering vortex chamber 124 from central
port 122 primarily travels in a radial direction within vortex chamber 124, as indicted by the
arrows, before exiting through lateral port 126 with little spiraling within vortex chamber 124
and without experiencing the associated frictional and centrifugal losses. Consequently,
production fluid passing through flow control component 114 that enters vortex chamber 124
primarily radially encounters little resistance and passes therethrough relatively unimpeded
enabling a much higher production flowrate as compared to the production flowrate through
flow control component 112.
[0036] Even though flow control components 112, 114 have been described and depicted
with a particular design, those skilled in the art will recognize that the design of the flow
control components will be determined based upon factors such as the desired flowrate, the
desired pressure drop, the type and composition of the injection and production fluids and the
like. For example, when the fluid flow resisting element within a flow control component is
a vortex chamber, the relative size, number and approach angle of the inlets can be altered to
direct fluids into the vortex chamber to increase or decrease the spiral effects, thereby
increasing or decreasing the resistance to flow and providing a desired flow pattern in the
vortex chamber. In addition, the vortex chamber can include flow vanes or other directional
devices, such as grooves, ridges, waves or other surface shaping, to direct fluid flow within
the chamber or to provide different or additional flow resistance. It should be noted by those
skilled in the art that even though the vortex chambers can be cylindrical, as shown, flow
control components of the present invention could have vortex chambers having alternate
shapes including, but not limited to, right rectangular, oval, spherical, spheroid and the like.
As such, it should be understood by those skilled in the art that the particular design and
number of injection flow control components will be based upon the desired injection profile
with the production flow control components contributing little to the overall injection
flowrate while the particular design and number of production flow control components will
be based upon the desired production profile with the injection flow control components
contributing little to the overall production flowrate.
[0037] As illustrated in figures 3A-3B, use of flow control components 112, 114 enables
both production fluid flow control and injection fluid flow control. In the illustrated
examples, flow control component 114 provides a greater resistance to fluid flow than flow
control component 112 during the injection phase of well operations while flow control
component 112 provide a greater resistance to fluid flow than flow control component 114
during the production phase of well operations. Unlike complicated and expensive prior art
systems that required one set of flow control components for production and another set flow
control components for injection along with the associated check valves to prevent reverse
flow, the present invention is able to achieve the desired flow and pressure regimes for both
the production direction and the injection direction utilizing solid state flow control
components operable for bidirectional flow with direction dependent flow resistance.
[0038] Even though flow control components 112, 114 have been described and depicted
as having fluid diodes in the form of vortex diodes, it should be understood by those skilled
in the art that flow control components of the present invention could have other types of
fluid diodes that create direction dependent flow resistance. For example, as depicted in
figures 4A-4B, a fluid flow control system 130 has two opposing flow control components
132, 134 having fluid diodes in the form of scroll diodes that provide direction dependent
flow resistance. In the illustrated embodiment, flow control component 132 is an injection
flow control component and flow control component 134 is a production flow control
component.
[0039] Figure 4A represents an injection phase of well operations. Injection flow is
depicted as arrows 136 in flow control component 132 and as arrows 138 in flow control
component 134. As illustrated, injection fluid 138 passes through a converging nozzle 140
into a sudden enlargement that has an axial annular cup 142 wherein the fluid separates at
nozzle throat and enters annular cup 142 that directs fluid back toward incoming flow. The
fluid must then turn again to pass annular cup 142 and enter a sudden enlargement region
144. Consequently, injection fluid passing through flow control component 134 encounters
significant resistance which results in a significant reduction in the injection flowrate
therethrough. At the same time, injection fluid 136 passes through region 146, around
annular cup 148 and through the throat into a diffuser of nozzle 150 with minimum losses.
Consequently, injection fluid passing through flow control component 132 encounters little
resistance and passes therethrough relatively unimpeded enabling a much higher injection
flowrate as compared to the injection flowrate through flow control component 134.
[0040] Figure 4B represents a production phase of well operations. Production flow is
depicted as arrows 152 in flow control component 132 and as arrows 154 in flow control
component 134. As illustrated, production fluid 152 passes through converging nozzle 150
into the sudden enlargement with axial annular cup 148 wherein the fluid separates at the
nozzle throat and enters annular cup 148 that directs fluid back toward incoming flow. The
fluid must then turn again to pass annular cup 148 and enter sudden enlargement region 146.
Consequently, production fluid passing through flow control component 132 encounters
significant resistance which results in a significant reduction in the production flowrate
therethrough. At the same time, production fluid 154 passes through region 144, around
annular cup 142 and through the throat into a diffuser of nozzle 140 with minimum losses.
Consequently, production fluid passing through flow control component 134 encounters little
resistance and passes therethrough relatively unimpeded enabling a much higher production
flowrate as compared to the production flowrate through flow control component 132.
[0041] In another example, as depicted in figures 5A-5B, a fluid flow control system 160
has two opposing flow control components 162, 164 having fluid diodes in the form of tesla
diodes that provide direction dependent flow resistance. In the illustrated embodiment, flow
control component 162 is an injection flow control component and flow control component
164 is a production flow control component. Figure 5A represents an injection phase of well
operations. Injection flow is depicted as arrows 166 in flow control component 162 and as
arrows 168 in flow control component 164. As illustrated, injection fluid 168 passes through
a series of connected branches and flow loops, such as loop 170, that cause the fluid to be
directed back toward forward flow. Consequently, injection fluid passing through flow
control component 164 encounters significant resistance which results in a significant
reduction in the injection flowrate therethrough. At the same time, injection fluid 166 passes
through the tesla diode without significant flow in the flow loops, such as loop 172.
Consequently, injection fluid passing through flow control component 162 encounters little
resistance and passes therethrough relatively unimpeded enabling a much higher injection
flowrate as compared to the injection flowrate through flow control component 164.
[0042] Figure 5B represents a production phase of well operations. Production flow is
depicted as arrows 174 in flow control component 162 and as arrows 176 in flow control
component 164. As illustrated, production fluid 174 passes through the series of connected
branches and flow loops, such as loop 172, that cause the fluid to be directed back toward
forward flow. Consequently, production fluid passing through flow control component 162
encounters significant resistance which results in a significant reduction in the production
flowrate therethrough. At the same time, injection fluid 176 passes through the tesla diode
without significant flow in the flow loops, such as loop 170. Consequently, production fluid
passing through flow control component 164 encounters little resistance and passes
therethrough relatively unimpeded enabling a much higher production flowrate as compared
to the production flowrate through flow control component 162.
[0043] Even though the flow control components of the present have been described and
depicted herein as single stage flow control components, it should be understood by those
skilled in the art that flow control components of the present invention could have multiple
flow control elements including at least one fluid diode that creates direction dependent flow
resistance. For example, as depicted in figures 6A-6B, a two stage flow control component
180 is depicted in injection and production operations, respectively, that may be used to
replace a single stage flow control component in a fluid flow control system described above.
Flow control component 180 may preferably be an injection flow control component capable
of generating critical flow of steam during, for example, a cyclic steam stimulation operation.
Flow control component 180 includes a first flow control element 182 in the form of a fluid
diode and namely a vortex diode in series with a second flow control element 184 in the form
of a converging/di verging nozzle.
[0044] During injection operations, as depicted in figure 6A, injection fluid 186 entering
vortex chamber 188 from central port 190 primarily travels in a radial direction within vortex
chamber 188, as indicted by the arrows. Injection fluid 186 exits vortex chamber 188 with
little spiraling and without experiencing the associated frictional and centrifugal losses.
Injection fluid 186 then enters nozzle 184 that has a throat portion 192 and diffuser portion
194. As injection fluid 186 approaches throat portion 192 its velocity increases and its
pressure decreases. In throat portion 192 injection fluid 186 reaches sonic velocity and
therefore critical flow under the proper upstream and downstream pressure regimes.
[0045] During production operations, as depicted in figure 6B, production fluid 196
enters flow control component 180 and pass through nozzle 184 with little resistance.
Production fluid 196 is then directed into vortex chamber 188 primarily in a tangentially
direction which causes the fluid to spiral around vortex chamber 188, as indicted by the
arrows, before eventually exiting through central port 190. Fluid spiraling around vortex
chamber 188 suffers from frictional and centrifugal losses. Consequently, production fluid
passing through flow control component 180 encounters significant resistance which results
in a significant reduction in the production flowrate therethrough.
[0046] As another example, depicted in figures 7A-7B, a two stage flow control
component 200 is depicted in injection and production operations, respectively, that may be
used to replace a single stage flow control component in a fluid flow control system
described above. Flow control component 200 may preferably be an injection flow control
component capable of substantially shutting off flow of an undesired fluid, for example, a
hydrocarbon fluid during production operation. Flow control component 200 includes a first
flow control element 202 in the form of a fluid diode and namely a vortex diode in series with
a second flow control element 204 in the form of a fluid selector valve.
[0047] During injection operations, as depicted in figure 7A, injection fluid 206 entering
vortex chamber 208 from central port 210 primarily travels in a radial direction within vortex
chamber 208, as indicted by the arrows. Injection fluid 206 exits vortex chamber 208 with
little spiraling and without experiencing the associated frictional and centrifugal losses.
Injection fluid 206 then passes through fluid selector valve 204 with minimal resistance.
During production operations, as depicted in figure 7B, production fluid 212 enters flow
control component 200 and encounter fluid selector valve 204. In the illustrated
embodiment, fluid selector valve 204 includes a material 214, such as a polymer, that swells
when it comes in contact with hydrocarbons. As such, fluid selector valve 204 closes or
substantially closes the fluid path through flow control component 200. Any production fluid
212 that passes through fluid selector valve 204 is then directed into vortex chamber 208
primarily in a tangentially direction which causes the fluid to spiral around vortex chamber
208, as indicted by the arrows, before eventually exiting through central port 210. Together,
vortex chamber 208 and fluid selector valve 204 provide significant resistance to production
therethrough.
[0048] Figure 8 depicts a two stage flow control component 220 during production
operations that may be used to replace a single stage flow control component in a fluid flow
control system described above. Flow control component 220 may preferably be a
production flow control component. Flow control component 220 includes a first flow
control element 222 in the form of an inflow control device and namely a torturous path in
series with a second flow control element 224 in the form of a vortex diode. During
production operations, production fluid 226 enters flow control component 220 and encounter
torturous path 222 which serves as the primary flow regulator of production flow. Production
fluid 226 is then directed into vortex chamber 228 from central port 230 primarily in a radial
direction, as indicted by the arrows, with little spiraling and without experiencing the
associated frictional and centrifugal losses, before exit flow control component 220 through
lateral port 232. During injection operations (not pictured), injection fluid would enter vortex
chamber 228 primarily in a tangentially direction which causes the fluid to spiral around
vortex chamber 228 before eventually exiting through central port 230. The injection fluid
would then travel through torturous path 222. Together, vortex chamber 228 and torturous
path 222 provide significant resistance to injection flow therethrough.
[0049] Figure 9 depicts a two stage flow control component 240 during production
operations that may be used to replace a single stage flow control component in a fluid flow
control system described above. Flow control component 240 may preferably be a
production flow control component. Flow control component 240 includes a first flow
control element 242 in the form of an inflow control device and namely an orifice 244 in
series with a second flow control element 246 in the form of a vortex diode. During
production operations, production fluid 248 enters flow control component 240 and orifice
244 which serves as the primary flow regulator of production flow. Production fluid 248 is
then directed into vortex chamber 250 from central port 252 primarily in a radial direction, as
indicted by the arrows, with little spiraling and without experiencing the associated frictional
and centrifugal losses, before exit flow control component 240 through lateral port 254.
During injection operations (not pictured), injection fluid would enter vortex chamber 250
primarily in a tangentially direction which causes the fluid to spiral around vortex chamber
250 before eventually exiting through central port 252. The injection fluid would then travel
through orifice 244. Together, vortex chamber 250 and orifice 244 provide significant
resistance to injection flow therethrough.
[0050] Even though figures 8-9 have described and depicted particular inflow control
devices in a two stage flow control component for use in a fluid flow control system of the
present invention, it should be understood by those skilled in the art that other types of inflow
control devices may be used in a two stage flow control component for use in a fluid flow
control system of the present invention. Also, even though figures 6A-9 have described and
depicted two stage flow control components for use in a fluid flow control system of the
present invention, it should be understood by those skilled in the art that flow control
components having other numbers of stages are possible and are considered within the scope
of the present invention.
[0051] Referring next to figures 10A-10B, therein is depicted a portion of a fluid flow
control system having two stage flow control components with directional dependent flow
resistance, during injection and production operations, respectively, that is generally
designated 300. In the illustrated section, two opposing two stage flow control components
302, 304 are depicted wherein flow control component 302 is an injection flow control
component and flow control component 304 is a production flow control component. As
illustrated, flow control component 302 includes two fluid diodes in the form of vortex
diodes 306, 308 in series with one another. Vortex diode 306 has a central port 310, a vortex
chamber 312 and a lateral port 314. Vortex diode 308 has a central port 316, a vortex
chamber 318 and a lateral port 320. Likewise, flow control component 304 includes two
fluid diodes in the form of vortex diodes 322, 324 in series with one another. Vortex diode
322 has a central port 326, a vortex chamber 328 and a lateral port 330. Vortex diode 324
has a central port 332, a vortex chamber 334 and a lateral port 336.
[0052] Figure 10A represents an injection phase of well operations. Injection flow is
depicted as arrows 338 in flow control component 302 and as arrows 340 in flow control
component 304. As illustrated, injection fluid 340 entering flow control component 304 at
lateral port 330 is directed into vortex chamber 328 primarily in a tangentially direction
which causes the fluid to spiral around vortex chamber 328, as indicted by the arrows, before
eventually exiting through central port 326. Injection fluid 340 is then directed into vortex
chamber 334 primarily in a tangentially direction which causes the fluid to spiral around
vortex chamber 334, as indicted by the arrows, before eventually exiting through central port
332. Injection fluid 340 suffers from frictional and centrifugal losses passing through flow
control component 304. Consequently, injection fluid passing through flow control
component 304 encounters significant resistance which results in a significant reduction in
the injection flowrate therethrough.
[0053] At the same time, injection fluid 338 entering vortex chamber 312 from central
port 310 primarily travels in a radial direction within vortex chamber 312, as indicted by the
arrows, before exiting through lateral port 314 with little spiraling within vortex chamber 312
and without experiencing the associated frictional and centrifugal losses. Injection fluid 338
then enters vortex chamber 318 from central port 316 primarily traveling in a radial direction
within vortex chamber 318, as indicted by the arrows, before exiting through lateral port 320
with little spiraling within vortex chamber 318 and without experiencing the associated
frictional and centrifugal losses. Consequently, injection fluid passing through flow control
component 302 encounters little resistance and passes therethrough relatively unimpeded
enabling a much higher injection flowrate as compared to the injection flowrate through flow
control component 304.
[0054] Figure 10B represents a production phase of well operations. Production flow is
depicted as arrows 342 in flow control component 302 and as arrows 344 in flow control
component 304. As illustrated, production fluid 342 entering flow control component 302 at
lateral port 320 is directed into vortex chamber 318 primarily in a tangentially direction
which causes the fluid to spiral around vortex chamber 318, as indicted by the arrows, before
eventually exiting through central port 316. Production fluid 342 is then directed into vortex
chamber 312 primarily in a tangentially direction which causes the fluid to spiral around
vortex chamber 312, as indicted by the arrows, before eventually exiting through central port
310. Fluid spiraling around vortex chambers 312, 318 suffers from frictional and centrifugal
losses. Consequently, production fluid passing through flow control component 302
encounters significant resistance which results in a significant reduction in the production
flowrate therethrough.
[0055] At the same time, production fluid 344 entering vortex chamber 334 from central
port 332 primarily travels in a radial direction within vortex chamber 334, as indicted by the
arrows, before exiting through lateral port 336 with little spiraling within vortex chamber 334
and without experiencing the associated frictional and centrifugal losses. Production fluid
344 then enters vortex chamber 328 from central port 326 primarily traveling in a radial
direction within vortex chamber 328, as indicted by the arrows, before exiting through lateral
port 330 with little spiraling within vortex chamber 328 and without experiencing the
associated frictional and centrifugal losses. Consequently, production fluid passing through
flow control component 304 encounters little resistance and passes therethrough relatively
unimpeded enabling a much higher production flowrate as compared to the production
flowrate through flow control component 302.
[0056] While this invention has been described with reference to illustrative
embodiments, this description is not intended to be construed in a limiting sense. Various
modifications and combinations of the illustrative embodiments as well as other
embodiments of the invention will be apparent to persons skilled in the art upon reference to
the description. It is, therefore, intended that the appended claims encompass any such
modifications or embodiments.
What is claimed is:
1. A bidirectional downhole fluid flow control system comprising:
at least one injection flow control component having direction dependent flow
resistance; and
at least one production flow control component in parallel with the at least one
injection flow control component and having direction dependent flow resistance,
wherein, injection fluid flow experiences a greater flow resistance through the at least
one production flow control component than through the at least one injection flow control
component; and
wherein, production fluid flow experiences a greater flow resistance through the at
least one injection flow control component than through the at least one production flow
control component.
2. The flow control system as recited in claim 1 wherein the at least one injection
flow control component further comprises a fluidic diode providing greater resistance to flow
in the production direction than in the injection direction.
3. The flow control system as recited in claim 1 wherein the at least one
production flow control component further comprises a fluidic diode providing greater
resistance to flow in the injection direction than in the production direction.
4. The flow control system as recited in claim 1 wherein the at least one injection
flow control component further comprises a vortex diode wherein injection fluid flow
entering the vortex diode travels primarily in a radial direction and wherein production fluid
flow entering the vortex diode travels primarily in a tangential direction.
5. The flow control system as recited in claim 1 wherein the at least one
production flow control component further comprises a vortex diode wherein production
fluid flow entering the vortex diode travels primarily in a radial direction and wherein
injection fluid flow entering the vortex diode travels primarily in a tangential direction.
6. The flow control system as recited in claim 1 wherein the at least one injection
flow control component further comprises a fluidic diode providing greater resistance to flow
in the production direction than in the injection direction in series with a nozzle having a
throat portion and a diffuser portion operable to enable critical flow therethrough.
7. The flow control system as recited in claim 1 wherein the at least one injection
flow control component further comprises a fluidic diode providing greater resistance to flow
in the production direction than in the injection direction in series with a fluid selector valve.
8. The flow control system as recited in claim 1 wherein the at least one
production flow control component further comprises a fluidic diode providing greater
resistance to flow in the injection direction than in the production direction in series with an
inflow control device.
9. A bidirectional downhole fluid flow control system comprising:
at least one injection vortex diode wherein injection fluid flow entering the injection
vortex diode travels primarily in a radial direction and wherein production fluid flow entering
the injection vortex diode travels primarily in a tangential direction; and
at least one production vortex diode in parallel with the at least one injection vortex
diode wherein production fluid flow entering the production vortex diode travels primarily in
a radial direction and wherein injection fluid flow entering the production vortex diode
travels primarily in a tangential direction.
10. The flow control system as recited in claim 9 wherein the at least one injection
vortex diode is in series with a nozzle having a throat portion and a diffuser portion operable
to enable critical flow therethrough.
11. The flow control system as recited in claim 9 wherein the at least one injection
vortex diode is in series with a fluid selector valve.
12. The flow control system as recited in claim 9 wherein the at least one
production vortex diode is in series with an inflow control device.
13. The flow control system as recited in claim 9 wherein the at least one injection
vortex diode further comprises a plurality of injection vortex diodes in parallel with each
other.
14. The flow control system as recited in claim 9 wherein the at least one
production vortex diode further comprises a plurality of production vortex diodes in parallel
with each other.
15. A bidirectional downhole fluid flow control method comprising:
providing a fluid flow control system at a target location downhole, the fluid flow
control system having at least one injection flow control component and at least one
production flow control component in parallel with the at least one injection flow control
component;
pumping an injection fluid from the surface into a formation through the fluid flow
control system such that the injection fluid experiencing greater flow resistance through the
production flow control component than through the injection flow control component; and
producing a formation fluid to the surface through the fluid flow control system such
that the production fluid experiencing greater flow resistance through the injection flow
control component than through the production flow control component.
16. The method as recited in claim 15 wherein pumping the injection fluid from
the surface into the formation through the fluid flow control system further comprises
pumping the injection fluid through parallel opposing fluid diodes, each having direction
dependent flow resistance.
17. The method as recited in claim 15 wherein producing the formation fluid to
the surface through the fluid flow control system further comprises producing the formation
fluid through parallel opposing fluid diodes, each having direction dependent flow resistance.
18. The method as recited in claim 15 wherein pumping the injection fluid from
the surface into a formation through the fluid flow control system further comprises pumping
the injection fluid through parallel opposing vortex diodes, each having direction dependent
flow resistance.
19. The method as recited in claim 15 wherein producing the formation fluid to
the surface through the fluid flow control system further comprises producing the formation
fluid through parallel opposing vortex diodes, each having direction dependent flow
resistance.
20. The method as recited in claim 15 wherein pumping the injection fluid from
the surface into the formation through the fluid flow control system further comprises
pumping the injection fluid through an injection fluid diode having direction dependent flow
resistance and a nozzle in series with the fluid diode, the nozzle having a throat portion and a
diffuser portion operable to enable critical flow therethrough.
2 1. A bidirectional downhole fluid flow control system comprising:
at least one injection flow control component having direction dependent flow
resistance; and
at least one production flow control component in parallel with the at least one
injection flow control component,
wherein, inflow of production fluid experiences a greater flow resistance through the
at least one injection flow control component than outflow of injection fluid through the at
least one injection flow control component.
22. The flow control system as recited in claim 2 1 wherein the at least one
production flow control has direction dependent flow resistance wherein outflow of injection
fluid experiences a greater flow resistance through the at least one injection flow control
component than inflow of production fluid through the at least one injection flow control
component.
23. The flow control system as recited in claim 2 1 wherein the at least one
injection flow control component further comprises a vortex diode wherein injection fluid
flow entering the vortex diode travels primarily in a radial direction and wherein production
fluid flow entering the vortex diode travels primarily in a tangential direction.
24. The flow control system as recited in claim 2 1 wherein the at least one
injection flow control component further comprises a fluidic diode providing greater
resistance to flow in the production direction than in the injection direction in series with a
nozzle having a throat portion and a diffuser portion operable to enable critical flow
therethrough.
25. The flow control system as recited in claim 21 wherein the at least one
production flow control component further comprises an inflow control device.