CROSS-REFERENCE TO RELATED APPLICATION
BACKGROUND
[0002] This disclosure relates generally to equipment utilized and operations performed
in conjunction with a subterranean well and, in an example described below, more particularly
provides a series configuration of variable flow restrictors.
[0003] In a hydrocarbon production well, it is many times beneficial to be able to regulate
flow of fluids from an earth formation into a wellbore. A variety of purposes may
be served by such regulation, including prevention of water or gas coning, minimizing
sand production, minimizing water and/or gas production, maximizing oil and/or gas
production, balancing production among zones, etc.
[0004] In an injection well, it is typically desirable to evenly inject water, steam, gas,
etc., into multiple zones, so that hydrocarbons are displaced evenly through an earth
formation, without the injected fluid prematurely breaking through to a production
wellbore. Thus, the ability to regulate flow of fluids from a wellbore into an earth
formation can also be beneficial for injection wells.
[0005] Therefore, it will be appreciated that advancements in the art of controlling fluid
flow in a well would be desirable in the circumstances mentioned above, and such advancements
would also be beneficial in a wide variety of other circumstances.
SUMMARY
[0006] In the disclosure below, a variable flow resistance system is provided which brings
improvements to the art of regulating fluid flow in wells. One example is described
below in which resistance to flow through a vortex device is dependent on a rotation
of a fluid composition as it enters the vortex device. Another example is described,
in which multiple vortex devices are connected in series.
[0007] In one aspect, the disclosure provides to the art a variable flow resistance system
for use in a subterranean well. The system can include a vortex device through which
a fluid composition flows. A resistance to flow of the fluid composition through the
vortex device is dependent on a rotation of the fluid composition at an inlet to the
vortex device.
[0008] In another aspect, a variable flow resistance system described below can include
a first vortex device having an outlet, and a second vortex device which receives
a fluid composition from the outlet of the first vortex device. A resistance to flow
of the fluid composition through the second vortex device is dependent on a rotation
of the fluid composition at the outlet of the first vortex device.
[0009] In yet another aspect, a variable flow resistance system can include a first vortex
device which causes increased rotation of a fluid composition at an outlet of the
first vortex device in response to an increase in a velocity of the fluid composition,
and a second vortex device which receives the fluid composition from the outlet of
the first vortex device. A resistance to flow of the fluid composition through the
second vortex device is dependent on the rotation of the fluid composition at the
outlet of the first vortex device.
[0010] A well device for installation in a wellbore in a subterranean zone is also described
below. In one example, the device includes a first fluid diode comprising a first
interior surface that defines a first interior chamber, and an outlet from the first
interior chamber, the first interior surface operable to direct fluid to rotate in
a rotational direction through the outlet; and a second fluid diode comprising a second
interior surface that defines a second interior chamber in fluid communication with
the outlet, the second interior surface operable to direct fluid to rotate in the
rotational direction in response to receiving the fluid rotating in the rotational
direction through the outlet.
[0011] The disclosure below also describes a method of controlling flow in a wellbore in
a subterranean zone. An example is described in which the method comprises communicating
fluid through a first fluid diode and a second fluid diode in a flow path between
an interior and an exterior of a well device in the subterranean zone. Communicating
the fluid through the first fluid diode and the second fluid diode can cause the fluid
to rotate within the first fluid diode in a rotational direction and to rotate within
the second fluid diode in the rotational direction.
[0012] These and other features, advantages and benefits will become apparent to one of
ordinary skill in the art upon careful consideration of the detailed description of
representative examples below and the accompanying drawings, in which similar elements
are indicated in the various figures using the same reference numbers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013]
FIG. 1 is a representative partially cross-sectional view of a well system which can
embody principles of the present disclosure.
FIG. 2 is an enlarged scale representative cross-sectional view of a well screen and
a variable flow resistance system which may be used in the well system of FIG. 1.
FIGS. 3A & B are representative "unrolled" cross-sectional views of one configuration
of the variable flow resistance system, taken along line 3-3 of FIG. 2.
FIG. 4 is a representative cross-sectional view of another configuration of the variable
flow resistance system.
FIG. 5 is a representative cross-sectional of the variable flow resistance system
of FIG. 4, taken along line 5-5.
FIGS. 6A & B are representative cross-sectional views the variable flow resistance
system of FIG. 4, depicting changes in flow resistance resulting from changes in characteristics
of a fluid composition.
DETAILED DESCRIPTION
[0014] Representatively illustrated in FIG. 1 is a well system 10 which can embody principles
of this disclosure. As depicted in FIG. 1, a wellbore 12 has a generally vertical
uncased section 14 extending downwardly from casing 16, as well as a generally horizontal
uncased section 18 extending through an earth formation 20.
[0015] A tubular string 22 (such as a production tubing string) is installed in the wellbore
12. Interconnected in the tubular string 22 are multiple well screens 24, variable
flow resistance systems 25 and packers 26.
[0016] The packers 26 seal off an annulus 28 formed radially between the tubular string
22 and the wellbore section 18. In this manner, fluids 30 may be produced from multiple
intervals or zones of the formation 20 via isolated portions of the annulus 28 between
adjacent pairs of the packers 26.
[0017] Positioned between each adjacent pair of the packers 26, a well screen 24 and a variable
flow resistance system 25 are interconnected in the tubular string 22. The well screen
24 filters the fluids 30 flowing into the tubular string 22 from the annulus 28. The
variable flow resistance system 25 variably restricts flow of the fluids 30 into the
tubular string 22, based on certain characteristics of the fluids.
[0018] At this point, it should be noted that the well system 10 is illustrated in the drawings
and is described herein as merely one example of a wide variety of well systems in
which the principles of this disclosure can be utilized. It should be clearly understood
that the principles of this disclosure are not limited at all to any of the details
of the well system 10, or components thereof, depicted in the drawings or described
herein.
[0019] For example, it is not necessary in keeping with the principles of this disclosure
for the wellbore 12 to include a generally vertical wellbore section 14 or a generally
horizontal wellbore section 18. It is not necessary for fluids 30 to be only produced
from the formation 20 since, in other examples, fluids could be injected into a formation,
fluids could be both injected into and produced from a formation, etc.
[0020] It is not necessary for one each of the well screen 24 and variable flow resistance
system 25 to be positioned between each adjacent pair of the packers 26. It is not
necessary for a single variable flow resistance system 25 to be used in conjunction
with a single well screen 24. Any number, arrangement and/or combination of these
components may be used.
[0021] It is not necessary for any variable flow resistance system 25 to be used with a
well screen 24. For example, in injection operations, the injected fluid could be
flowed through a variable flow resistance system 25, without also flowing through
a well screen 24.
[0022] It is not necessary for the well screens 24, variable flow resistance systems 25,
packers 26 or any other components of the tubular string 22 to be positioned in uncased
sections 14, 18 of the wellbore 12. Any section of the wellbore 12 may be cased or
uncased, and any portion of the tubular string 22 may be positioned in an uncased
or cased section of the wellbore, in keeping with the principles of this disclosure.
[0023] It should be clearly understood, therefore, that this disclosure describes how to
make and use certain examples, but the principles of the disclosure are not limited
to any details of those examples. Instead, those principles can be applied to a variety
of other examples using the knowledge obtained from this disclosure.
[0024] It will be appreciated by those skilled in the art that it would be beneficial to
be able to regulate flow of the fluids 30 into the tubular string 22 from each zone
of the formation 20, for example, to prevent water coning 32 or gas coning 34 in the
formation. Other uses for flow regulation in a well include, but are not limited to,
balancing production from (or injection into) multiple zones, minimizing production
or injection of undesired fluids, maximizing production or injection of desired fluids,
etc.
[0025] Examples of the variable flow resistance systems 25 described more fully below can
provide these benefits by increasing resistance to flow if a fluid velocity increases
beyond a selected level (e.g., to thereby balance flow among zones, prevent water
or gas coning, etc.), and/or increasing resistance to flow if a fluid viscosity decreases
below a selected level (e.g., to thereby restrict flow of an undesired fluid, such
as water or gas, in an oil producing well).
[0026] As used herein, the term "viscosity" is used to indicate any of the rheological properties
including kinematic viscosity, yield strength, viscoplasticity, surface tension, wettability,
etc.
[0027] Whether a fluid is a desired or an undesired fluid depends on the purpose of the
production or injection operation being conducted. For example, if it is desired to
produce oil from a well, but not to produce water or gas, then oil is a desired fluid
and water and gas are undesired fluids. If it is desired to produce gas from a well,
but not to produce water or oil, the gas is a desired fluid, and water and oil are
undesired fluids. If it is desired to inject steam into a formation, but not to inject
water, then steam is a desired fluid and water is an undesired fluid.
[0028] If gas is being flowed, it can be difficult to restrict flow of the gas using conventional
techniques, which typically involve interposing small diameter passages, orifices,
etc. in the gas flow. Unfortunately, these devices can have an increased volumetric
flow rate when gas is flowing instead of oil or another fluid, and can result in erosion
problems.
[0029] Note that, at downhole temperatures and pressures, hydrocarbon gas can actually be
completely or partially in liquid phase. Thus, it should be understood that when the
term "gas" is used herein, supercritical, liquid, condensate and/or gaseous phases
are included within the scope of that term.
[0030] Referring additionally now to FIG. 2, an enlarged scale cross-sectional view of one
of the variable flow resistance systems 25 and a portion of one of the well screens
24 is representatively illustrated. In this example, a fluid composition 36 (which
can include one or more fluids, such as oil and water, liquid water and steam, oil
and gas, gas and water, oil, water and gas, etc.) flows into the well screen 24, is
thereby filtered, and then flows into an inlet 38 of the variable flow resistance
system 25.
[0031] A fluid composition can include one or more undesired or desired fluids. Both steam
and water can be combined in a fluid composition. As another example, oil, water and/or
gas can be combined in a fluid composition.
[0032] Flow of the fluid composition 36 through the variable flow resistance system 25 is
resisted based on one or more characteristics (such as viscosity, velocity, density,
etc.) of the fluid composition. The fluid composition 36 is then discharged from the
variable flow resistance system 25 to an interior of the tubular string 22 via an
outlet 40.
[0033] In other examples, the well screen 24 may not be used in conjunction with the variable
flow resistance system 25 (e.g., in injection operations), the fluid composition 36
could flow in an opposite direction through the various elements of the well system
10 (e.g., in injection operations), a single variable flow resistance system could
be used in conjunction with multiple well screens, multiple variable flow resistance
systems could be used with one or more well screens, the fluid composition could be
received from or discharged into regions of a well other than an annulus or a tubular
string, the fluid composition could flow through the variable flow resistance system
prior to flowing through the well screen, any other components could be interconnected
upstream or downstream of the well screen and/or variable flow resistance system,
etc. Thus, it will be appreciated that the principles of this disclosure are not limited
at all to the details of the example depicted in FIG. 2 and described herein.
[0034] Although the well screen 24 depicted in FIG. 2 is of the type known to those skilled
in the art as a wire-wrapped well screen, any other types or combinations of well
screens (such as sintered, expanded, pre-packed, wire mesh, etc.) may be used in other
examples. Additional components (such as shrouds, shunt tubes, lines, instrumentation,
sensors, inflow control devices, etc.) may also be used, if desired.
[0035] The variable flow resistance system 25 is depicted in simplified form in FIG. 2,
but in a preferred example the system can include various passages and devices for
performing various functions, as described more fully below. In addition, the system
25 can at least partially extend circumferentially about the tubular string 22, or
the system may be formed in a wall of a tubular structure interconnected as part of
the tubular string.
[0036] In other examples, the system 25 may not extend circumferentially about a tubular
string or be formed in a wall of a tubular structure. For example, the system 25 could
be formed in a flat structure, etc. The system 25 could be in a separate housing that
is attached to the tubular string 22, or it could be oriented so that the axis of
the outlet 40 is parallel to the axis of the tubular string. The system 25 could be
on a logging string or attached to a device that is not tubular in shape. Any orientation
or configuration of the system 25 may be used in keeping with the principles of this
disclosure.
[0037] Referring additionally now to FIGS. 3A & B, a more detailed cross-sectional view
of one example of the system 25 is representatively illustrated. The system 25 is
depicted in FIGS. 3A & B as if it is "unrolled" from its circumferentially extending
configuration to a generally planar configuration.
[0038] As described above, the fluid composition 36 enters the system 25 via the inlet 38,
and exits the system via the outlet 40. A resistance to flow of the fluid composition
36 through the system 25 varies based on one or more characteristics of the fluid
composition.
[0039] The inlet 38, the outlet 40, and a flow passage 42 and flow chamber 44 through which
the fluid composition 36 flows between the inlet and the outlet, are elements of a
vortex device 46 which restricts flow of the fluid composition based on certain characteristics
of the fluid composition. Rotational flow of the fluid composition 36 increases in
the chamber 44, thereby increasing restriction to flow through the chamber, for example,
when a velocity of the fluid composition increases, when a viscosity of the fluid
composition decreases, when a density of the fluid composition increases, and/or when
a ratio of desired fluid to undesired fluid in the fluid composition decreases.
[0040] As depicted in FIG. 3A, the chamber 44 is generally cylindrical-shaped, and the flow
passage 42 intersects the chamber tangentially, so that fluid entering the chamber
via the inlet 48 tends to flow clockwise (as viewed in FIG. 3A) about the outlet 40.
A bypass passage 50 intersects the passage 42 downstream of the inlet 38, and the
bypass passage also intersects the chamber 44 tangentially. However, fluid entering
the chamber 44 through the bypass passage 50 via an inlet 52 tends to flow counterclockwise
(as viewed in FIG. 3A) about the outlet 40.
[0041] In FIG. 3A, a relatively high velocity and/or low viscosity fluid composition 36
flows through the flow passage 42 from the system inlet 38 to the flow chamber 44.
In contrast, a relatively low velocity and/or high viscosity fluid composition 36
flows through the flow passage 42 to the chamber 44 in FIG. 3B.
[0042] Only a small proportion of the fluid composition 36 flows to the chamber 44 via the
bypass passage 50 in FIG. 3A. Thus, a substantial proportion of the fluid composition
36 rotates in the chamber 44, spiraling with increasing rotational velocity toward
the outlet 40. Note that the rotation of the fluid composition 36 at the outlet 40
will increase as the velocity of the fluid composition entering the inlet 38 increases,
and as a viscosity of the fluid composition decreases.
[0043] A substantially larger proportion of the fluid composition flows to the chamber 44
via the bypass passage 50 in FIG. 3B. In this example, the flows entering the chamber
44 via the inlets 48, 52 are about equal. These flows effectively "cancel" or counteract
each other, so that there is relatively little rotational flow of the fluid composition
36 in the chamber 44.
[0044] It will be appreciated that the much more circuitous flow path taken by the fluid
composition 36 in the example of FIG. 3A dissipates more of the fluid composition's
energy at the same flow rate and, thus, results in more resistance to flow, as compared
to the much more direct flow path taken by the fluid composition in the example of
FIG. 3B. If oil is a desired fluid, and water and/or gas are undesired fluids, then
it will be appreciated that the variable flow resistance system 25 of FIGS. 3A & B
will provide less resistance to flow of the fluid composition 36 when it has an increased
ratio of desired to undesired fluid therein, and will provide greater resistance to
flow when the fluid composition has a decreased ratio of desired to undesired fluid
therein.
[0045] Since the chamber 44 in this example has a cylindrical shape with a central outlet
40, and the fluid composition 36 (at least in FIG. 3A) spirals about the chamber,
increasing in velocity as it nears the outlet, driven by a pressure differential from
the inlet 44 to the outlet, the chamber may be referred to as a "vortex" chamber.
[0046] Circular flow inducing structures 54 are used in the chamber 44 in the configuration
of FIGS. 3A & B. The structures 54 operate to maintain circular flow of the fluid
composition 36 about the outlet 40, or at least to impede inward flow of the fluid
composition toward the outlet, when the fluid composition does flow circularly about
the outlet. Openings 56 in the structures 54 permit the fluid composition 36 to eventually
flow inward to the outlet 40.
[0047] As discussed above, in FIG. 3A, the vortex device 46 is depicted in a situation in
which an increased velocity and/or reduced viscosity of the fluid composition 36 results
in a substantial proportion of the fluid composition flowing into the chamber 44 via
the inlet 48. The fluid composition 36, thus, spirals about the outlet 40 in the chamber
44, and a resistance to flow through the vortex device 46 increases. A reduced viscosity
can be due to a relatively low ratio of desired fluid to undesired fluid in the fluid
composition 36.
[0048] Relatively little of the fluid composition 36 flows into the chamber 44 via the inlet
52 in FIG. 3A, because the flow passage 50 is branched from the flow passage 42 in
a manner such that most of the fluid composition remains in the flow passage 42. At
relatively high velocities, high densities and/or low viscosities, the fluid composition
36 tends to flow past the flow passage 50.
[0049] In FIG. 3B, a velocity of the fluid composition 36 has decreased and/or a viscosity
of the fluid composition has increased, and as a result, proportionately more of the
fluid composition flows from the passage 42 and via the passage 50 to the inlet 52.
The increased viscosity of the fluid composition 36 may be due to an increased ratio
of desired to undesired fluids in the fluid composition.
[0050] Since, in FIG. 3B, the flows into the chamber 44 from the two inlets 48, 52 are oppositely
directed (or at least the flow of the fluid composition through the inlet 52 opposes
the flow through the inlet 48), they counteract each other. Thus, the fluid composition
36 flows more directly to the outlet 40 and a resistance to flow through the vortex
device 46 is decreased, and the fluid composition has reduced (or no) rotation at
the outlet 40.
[0051] Referring additionally now to FIG. 4, another configuration of the variable flow
resistance system 25 is representatively illustrated. In this configuration, the vortex
device 46 is used in series with two additional vortex devices 58, 60. Although three
vortex devices 46, 58, 60 are depicted in FIG. 4, it will be appreciated that any
number of vortex devices may be connected in series, in keeping with the principles
of this disclosure.
[0052] An outlet 62 of the vortex device 46 corresponds to an inlet of the vortex device
58, and an outlet 64 of the vortex device 58 corresponds to an inlet of the vortex
device 60. The fluid composition 36 flows from the system 25 inlet 38 to the chamber
44, from the chamber 44 to the vortex device 58 via the outlet/inlet 62, from the
outlet/inlet 62 to a vortex chamber 66 of the vortex device 58, from the chamber 66
to the vortex device 60 via the outlet/inlet 64, from the outlet/inlet 64 to a vortex
chamber 68 of the vortex device 60, and from the chamber 68 to the outlet 40 of the
system 25.
[0053] Each of the vortex devices 58, 60 includes two passages 70, 72 and 74, 76, respectively,
which function somewhat similar to the passages 42, 50 of the vortex device 46. However,
the proportions of the fluid composition 36 which flows through each of the passages
70, 72 and 74, 76 varies based on a rotation of the fluid composition as it enters
the respective vortex device 58, 60, as described more fully below.
[0054] Referring additionally now to FIG. 5, a cross-sectional view of the variable flow
resistance system 25 is representatively illustrated, as viewed along line 5-5 of
FIG. 4. In this view, the manner in which the outlet/inlet 62 and outlet/inlet 64
provide fluid communication between the vortex devices 46, 58, 60 can be readily seen.
[0055] In FIG. 5, it may also be seen that the vortex devices 46, 58, 60 are "stacked" in
a compact manner, alternating orientation back and forth. However, it will be appreciated
that the vortex devices 46, 58, 60 could be otherwise arranged, in keeping with the
principles of this disclosure.
[0056] Referring additionally now to FIGS. 6A & B, the variable flow resistance system 25
of FIGS. 4 & 5 is depicted, with a relatively low viscosity, high density and/or high
velocity fluid composition 36 flowing through the system in FIG. 6A, and with a relatively
high viscosity, low density and/or low velocity fluid composition flowing through
the system in FIG. 6B. These examples demonstrate how the resistance to flow through
the system 25 varies based on certain characteristics of the fluid composition 36.
[0057] In FIG. 6A, significant spiraling flow of the fluid composition 36 is present in
the vortex device 46 (similar to that described above in relation to FIG. 3A). As
a result, the fluid composition 36 is rotating significantly when it flows from the
chamber 44 to the vortex device 58 via the outlet/inlet 62.
[0058] This rotational flow of the fluid composition 36 causes a greater proportion of the
fluid composition to flow through the passage 70, as compared to the proportion of
the fluid composition which flows through the passage 72. The manner in which the
rotating fluid composition 36 impinges on the curved walls of the passages 70, 72
at their intersection with the outlet/inlet 62 causes this difference in the proportions
of the fluid composition which flows through each of the passages.
[0059] Since a greater proportion of the fluid composition 36 flows into the chamber 66
of the vortex device 58 via the passage 70, the fluid composition rotates within the
chamber 66, similar to the manner in which the fluid composition flows spirally through
the chamber 44 of the vortex device 46. This spiraling flow of the fluid composition
36 through the chamber 66 generates resistance to flow, with the resistance to flow
increasing with increased rotational flow of the fluid composition in the chamber.
[0060] The fluid composition 36 rotates as it exits the chamber 66 via the outlet/inlet
64. This rotational flow of the fluid composition 36 causes a greater proportion of
the fluid composition to flow through the passage 74, as compared to the proportion
of the fluid composition which flows through the passage 76. Similar to that described
above for the vortex chamber 58, the manner in which the rotating fluid composition
36 impinges on the curved walls of the passages 74, 76 at their intersection with
the outlet/inlet 64 causes this difference in the proportions of the fluid composition
which flows through each of the passages.
[0061] Since a greater proportion of the fluid composition 36 flows into the chamber 68
of the vortex device 60 via the passage 74, the fluid composition rotates within the
chamber 68, similar to the manner in which the fluid composition flows spirally through
the chamber 66 of the vortex device 58. This spiraling flow of the fluid composition
36 through the chamber 68 generates resistance to flow, with the resistance to flow
increasing with increased rotational flow of the fluid composition in the chamber.
[0062] Thus, with the relatively high velocity and/or low viscosity fluid composition 36
in FIG. 6A, rotational flow and resistance to flow is increased in each of the vortex
devices 46, 58, 60, so that overall flow resistance is much greater than that which
would have been provided by only the single vortex device 46. In addition, the rotational
flow through the chambers 66, 68 of the vortex devices 58, 60 is due to the rotational
flow of the fluid composition 36 at each of the outlet/inlets 62, 64.
[0063] In FIG. 6B, a relatively high viscosity and/or low velocity fluid composition 36
flows through the system 25. Note that rotational flow of the fluid composition 36
in each of the chambers 44, 66, 68 is significantly reduced, and so the resistance
to flow of the fluid composition through the chambers is also significantly reduced.
Thus, the resistance to flow of the relatively high viscosity and/or low velocity
fluid composition 36 is much less in FIG. 6B, as compared to the resistance to flow
of the relatively low viscosity and/or high velocity fluid composition in FIG. 6A.
[0064] Note that any of the features of any of the configurations of the system 25 described
above may be included in any of the other configurations of the system and, thus,
it should be understood that these features are not exclusive to any one particular
configuration of the system. The system 25 can be used in any type of well system
(e.g., not only in the well system 10), and for accomplishing various purposes in
various well operations, including but not limited to injection, stimulation, completion,
production, conformance, drilling operations, etc.
[0065] It will be appreciated that the system 25 of FIGS. 4-6B provides significant advancements
to the art of controlling flow in a well. The resistance to flow of the fluid composition
36 through the system 25 can be substantially increased by connecting the vortex devices
46, 58, 60 in series, and by resisting flow of the fluid composition in response to
its rotation as it passes from one vortex device to the next.
[0066] The above disclosure provides to the art a variable flow resistance system 25 for
use in a subterranean well. The system 25 can include a vortex device 58 or 60 through
which a fluid composition 36 flows. A resistance to flow of the fluid composition
36 through the vortex device 58 or 60 is dependent on a rotation of the fluid composition
36 at an inlet 62 or 64 to the vortex device 58 or 60.
[0067] The resistance to flow of the fluid composition 36 through the vortex device 58 or
60 can increase in response to an increased rotation of the fluid composition 36 at
the inlet 62 or 64 to the vortex device 58 or 60.
[0068] The rotation of the fluid composition 36 at the inlet 62 or 64 can increase in response
to a decrease in viscosity of the fluid composition 36.
[0069] The rotation of the fluid composition 36 at the inlet 62 or 64 can increase in response
to an increase in velocity of the fluid composition 36.
[0070] The rotation of the fluid composition 36 at the inlet 62 or 64 can increase in response
to a decrease in a ratio of desired to undesired fluid in the fluid composition 36.
[0071] An outlet 64 of the vortex device 58 can comprise an inlet 64 of another vortex device
60. The inlet 64 of the vortex device 60 can comprise an outlet 64 of another vortex
device 58.
[0072] The vortex device 58 can comprise at least first and second passages 70, 72 which
receive the fluid composition 36 from an outlet 62 of another vortex device 46. A
difference in proportions of the fluid composition 36 which flows through the respective
first and second passages 70, 72 is dependent on the rotation of the fluid composition
36 at the outlet 62. The difference in the proportions of the fluid composition 36
which flows through the first and second passages 70, 72 may increase in response
to an increase in velocity of the fluid composition 36.
[0073] Rotation of the fluid composition 36 in a vortex chamber 66 increases in response
to an increase in the difference in the proportions of the fluid composition 36 which
flows through the first and second passages 70, 72.
[0074] The above disclosure also describes a variable flow resistance system 25 which can
include a first vortex 46 device having an outlet 62, and a second vortex device 58
which receives a fluid composition 36 from the outlet 62 of the first vortex device
46. A resistance to flow of the fluid composition 36 through the second vortex device
58 can be dependent on a rotation of the fluid composition 36 at the outlet 62 of
the first vortex device 46.
[0075] The rotation of the fluid composition 36 at the outlet 62 may increase in response
to a decrease in viscosity of the fluid composition 36, in response to an increase
in velocity of the fluid composition 36 and/or in response to a decrease in a ratio
of desired to undesired fluid in the fluid composition 36.
[0076] The resistance to flow of the fluid composition 36 through the second vortex device
58 can increase in response to an increase in the rotation of the fluid composition
36 at the outlet 62 of the first vortex device 46.
[0077] An outlet 64 of the second vortex device 58 can comprise an inlet 64 of a third vortex
device 60.
[0078] The second vortex device 58 can include at least first and second passages 70, 72
which receive the fluid composition 36 from the outlet 62 of the first vortex device
46. A difference in proportions of the fluid composition 36 which flow through the
respective first and second passages 70, 72 is dependent on the rotation of the fluid
composition 36 at the outlet 62 of the first vortex device 46.
[0079] The difference in the proportions of the fluid composition 36 which flows through
the first and second passages 70, 72 may increase in response to an increase in velocity
of the fluid composition 36.
[0080] Rotation of the fluid composition 36 in a vortex chamber 66 of the second vortex
device 58 may increase in response to an increase in the difference in the proportions
of the fluid composition 36 which flows through the first and second passages 70,
72.
[0081] The above disclosure also describes a variable flow resistance system 25 which can
include a first vortex device 46 which causes increased rotation of a fluid composition
36 at an outlet 62 of the first vortex device 46 in response to an increase in a velocity
of the fluid composition 36, and a second vortex device 58 which receives the fluid
composition 36 from the outlet 62 of the first vortex device 46. A resistance to flow
of the fluid composition 36 through the second vortex device 58 may be dependent on
the rotation of the fluid composition 36 at the outlet 62 of the first vortex device
46.
[0082] Note that the vortex devices 46, 58, 60 may be of the type known to those skilled
in the art as fluid "diodes."
[0083] A well device (e.g., the variable flow resistance system 25) for installation in
a wellbore 12 in a subterranean zone (e.g., in formation 20) can include a first fluid
diode (e.g., vortex device 46) comprising: a first interior surface 80 (see FIGS.
4 & 5) that defines a first interior chamber 44, and an outlet 62 from the first interior
chamber 44, the first interior surface 80 operable to direct fluid (e.g., fluid composition
36) to rotate in a rotational direction through the outlet 62; and a second fluid
diode (e.g., vortex device 58) comprising: a second interior surface 82 that defines
a second interior chamber 66 in fluid communication with the outlet 62, the second
interior surface 82 operable to direct fluid (e.g., fluid composition 36) to rotate
in the rotational direction in response to receiving the fluid rotating in the rotational
direction through the outlet 62.
[0084] The second fluid diode can include an inlet (in the FIGS. 4-6B example, the inlet
of the chamber 58 is the same as the outlet 62 of the chamber 44) operable to receive
the fluid 36 directly from the outlet 62. The second interior chamber 66 can comprise:
a cylindroidal chamber 66, a first flow passage 70 from the inlet 62 to the cylindroidal
chamber 66, and a second flow passage 72 from the inlet 62 to the cylindroidal chamber
66.
[0085] The second interior surface 82 may be operable to direct a majority of the fluid
36 to the first flow passage 70 in response to receiving the fluid 36 rotating in
the rotational direction through the inlet 62.
[0086] The first interior surface 80 may be operable to direct fluid 36 to rotate in a rotational
direction about a first axis of rotation 84, and the second interior surface 82 may
be operable to direct fluid 36 to rotate in a rotational direction about a second
axis of rotation 86. The first axis of rotation 84 can be parallel to the second axis
of rotation 86.
[0087] The first fluid diode 46 and the second fluid diode 58 may be in fluid communication
between an interior and an exterior of the well device (e.g., the variable flow resistance
system 25). The first fluid diode 46 and the second fluid diode 58 can be in fluid
communication between the interior and the exterior to communicate production fluid
36 from the exterior of the well device 25 to the interior of the well device 25.
The well device 25 may comprise a section of a completion string 22.
[0088] The first and second fluid diodes 46, 58 can be in fluid communication between the
interior and the exterior to communicate injection fluid 36 from the interior of the
well device 25 to the exterior of the well device 25. The well device 25 may comprise
a section of a working string 22.
[0089] The outlet 62 can comprise a first outlet 62, the first fluid diode 46 can further
comprise a first inlet 38, the first interior surface 80 may include a first side
perimeter surface 80 and first opposing end surfaces 88, a greatest distance between
the first opposing end surfaces 88 can be smaller than a largest dimension of the
first opposing end surfaces 88, and the first side perimeter surface 80 may be operable
to direct flow from the first inlet 38 to rotate about the first outlet 62.
[0090] The second fluid diode 58 can comprise a second inlet 62 operable to receive the
fluid 36 directly from the first outlet 62, the second interior surface 82 may include
a second side perimeter surface 82 and second opposing end surfaces 90, a greatest
distance between the second opposing end surfaces 90 may be smaller than a largest
dimension of the second opposing end surfaces 90, and the second side perimeter surface
82 can be operable to direct flow from the second inlet 62 to rotate about a second
outlet 64.
[0091] A method of controlling flow in a wellbore 12 in a subterranean zone 20 can include
communicating fluid 36 through a first fluid diode 46 and a second fluid diode 58
in a flow path between an interior and an exterior of a well device 25 in the subterranean
zone 20. Communicating the fluid 36 through the first fluid diode 46 and the second
fluid diode 58 can cause the fluid 36 to rotate within the first fluid diode 46 in
a rotational direction and to rotate within the second fluid diode 58 in the rotational
direction.
[0092] The fluid 36 may comprise a production or injection fluid.
[0093] Communicating the fluid 36 through the first fluid diode 46 and the second fluid
diode 58 can control a resistance to a flow of the fluid 36 between the interior and
the exterior based on a characteristic of the flow. The characteristic may comprise
at least one of viscosity, velocity or density.
[0094] A resistance to flow through the second fluid diode 58 can be based at least in part
on a characteristic of inflow received by the second fluid diode 58 from the first
fluid diode 46.
[0095] It is to be understood that the various examples described above may be utilized
in various orientations, such as inclined, inverted, horizontal, vertical, etc., and
in various configurations, without departing from the principles of the present disclosure.
The embodiments illustrated in the drawings are depicted and described merely as examples
of useful applications of the principles of the disclosure, which are not limited
to any specific details of these embodiments.
[0096] Of course, a person skilled in the art would, upon a careful consideration of the
above description of representative embodiments, readily appreciate that many modifications,
additions, substitutions, deletions, and other changes may be made to these specific
embodiments, and such changes are within the scope of the principles of the present
disclosure. Accordingly, the foregoing detailed description is to be clearly understood
as being given by way of illustration and example only, the spirit and scope of the
present invention being limited solely by the appended claims and their equivalents.
1. A well device for installation in a wellbore in a subterranean zone, comprising:
a first fluid diode comprising:
a first interior surface that defines a first interior chamber, and
an outlet from the first interior chamber, the first interior surface operable to
direct fluid to rotate in a rotational direction through the outlet; and
a second fluid diode comprising:
a second interior surface that defines a second interior chamber in fluid communication
with the outlet, the second interior surface operable to direct fluid to rotate in
the rotational direction in response to receiving the fluid rotating in the rotational
direction through the outlet.
2. The well device of claim 1, wherein the second fluid diode includes an inlet operable
to receive the fluid directly from the outlet, and the second interior chamber comprises:
a cylindroidal chamber;
a first flow passage from the inlet to the cylindroidal chamber; and
a second flow passage from the inlet to the cylindroidal chamber.
3. The well device of claim 2, wherein the second interior surface is operable to direct
a majority of the fluid to the first flow passage in response to receiving the fluid
rotating in the rotational direction through the inlet.
4. The well device of claim 1, wherein the first interior surface is operable to direct
fluid to rotate in the rotational direction about a first axis of rotation, and the
second interior surface is operable to direct fluid to rotate in the rotational direction
about a second axis of rotation, which is preferably parallel to the first axis of
rotation.
5. The well device of claim 1, wherein the first fluid diode and the second fluid diode
are in fluid communication between the interior and the exterior to communicate production
fluid from the exterior of the well device to the interior of the well device.
6. The well device of claim 5, wherein the well device comprises a section of a completion
string.
7. The well device of claim 1, wherein the first and second fluid diodes are in fluid
communication between the interior and the exterior to communicate injection fluid
from the interior of the well device to the exterior of the well device.
8. The well device of claim 4, wherein the well device comprises a section of a working
string.
9. The well device of claim 1, wherein the outlet comprises a first outlet, the first
fluid diode further comprises a first inlet, the first interior surface includes a
first side perimeter surface and first opposing end surfaces, a greatest distance
between the first opposing end surfaces is smaller than a largest dimension of the
first opposing end surfaces, and the first side perimeter surface is operable to direct
flow from the first inlet to rotate about the first outlet.
10. The well device of claim 9, wherein the second fluid diode further comprises a second
inlet operable to receive the fluid directly from the first outlet, the second interior
surface includes a second side perimeter surface and second opposing end surfaces,
a greatest distance between the second opposing end surfaces is smaller than a largest
dimension of the second opposing end surfaces, and the second side perimeter surface
is operable to direct flow from the second inlet to rotate about a second outlet.
11. A method of controlling flow in a wellbore in a subterranean zone, comprising:
communicating fluid through a first fluid diode and a second fluid diode in a flow
path between an interior and an exterior of a well device in the subterranean zone,
communicating the fluid through the first fluid diode and the second fluid diode causes
the fluid to rotate within the first fluid diode in a rotational direction and to
rotate within the second fluid diode in the rotational direction.
12. The method of claim 11, wherein the fluid comprises a production fluid or an injection
fluid.
13. The method of claim 11, wherein communicating the fluid through the first fluid diode
and the second fluid diode controls a resistance to a flow of the fluid between the
interior and the exterior based on a characteristic of the flow.
14. The method of claim 13, wherein the characteristic comprises at least one of viscosity,
velocity and density.
15. The method of claim 13, wherein a resistance to flow through the second fluid diode
is based at least in part on a characteristic of inflow received by the second fluid
diode from the first fluid diode.