U.S. patent application number 13/063952 was filed with the patent office on 2011-07-21 for jet eductor pump.
This patent application is currently assigned to KONINKLIJKE PHILIPS ELECTRONICS, N.V.. Invention is credited to Ronaldus Maria Aarts, Gerbern Kooijman, Okke Ouweltjes, Martijn Schellekens, Olaf Such.
Application Number | 20110176935 13/063952 |
Document ID | / |
Family ID | 41323544 |
Filed Date | 2011-07-21 |
United States Patent
Application |
20110176935 |
Kind Code |
A1 |
Kooijman; Gerbern ; et
al. |
July 21, 2011 |
JET EDUCTOR PUMP
Abstract
The invention provides a synthetic jet eductor pump that
includes a synthetic jet actuator coupled to a fluid conduit. The
synthetic jet actuator may include a vibratable membrane, an
actuating portion that vibrates the vibratable membrane, a pump
chamber coupled to the vibratable membrane, and a pump conduit in
fluid communication with the pump chamber such that vibration of
the membrane draws fluid into and ejects fluid from the pump
conduit to create a net momentum of fluid in a predetermined
direction. The fluid conduit may include a jet receiving portion
between intake and ejection portions thereof, wherein the jet
receiving portion is in fluid communication with the pump conduit.
The net momentum of fluid created by the synthetic jet actuator may
be communicated to the fluid conduit at the jet receiving portion
to create fluid flow in the fluid conduit from the intake portion
to the ejection portion.
Inventors: |
Kooijman; Gerbern; (Heeze,
NL) ; Aarts; Ronaldus Maria; (Geldrop, NL) ;
Ouweltjes; Okke; (Veldhoven, NL) ; Schellekens;
Martijn; (Eindhoven, NL) ; Such; Olaf;
(Eindhoven, NL) |
Assignee: |
KONINKLIJKE PHILIPS ELECTRONICS,
N.V.
EINDHOVEN
NL
|
Family ID: |
41323544 |
Appl. No.: |
13/063952 |
Filed: |
September 18, 2009 |
PCT Filed: |
September 18, 2009 |
PCT NO: |
PCT/IB2009/054106 |
371 Date: |
March 15, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61100413 |
Sep 26, 2008 |
|
|
|
Current U.S.
Class: |
417/54 ;
417/151 |
Current CPC
Class: |
F04F 5/16 20130101; F04F
5/00 20130101; F04F 7/00 20130101; F04F 5/10 20130101 |
Class at
Publication: |
417/54 ;
417/151 |
International
Class: |
F04F 5/00 20060101
F04F005/00; F04F 5/48 20060101 F04F005/48 |
Claims
1. A fluid pump comprising: a synthetic jet actuator that includes:
a vibratable membrane, an actuating portion that vibrates the
vibratable membrane, a pump chamber coupled to the vibratable
membrane, and a pump conduit in fluid communication with the pump
chamber such that vibration of the membrane draws fluid into the
pump conduit and ejects fluid from the pump conduit to create a net
momentum of fluid in a predetermined direction; and a fluid conduit
having an intake portion, an ejection portion, and a jet receiving
portion therebetween, wherein the jet receiving portion is in fluid
communication with the pump conduit, the intake portion arranged to
be placed in communication with a source of fluid, wherein the net
momentum of fluid is communicated to the fluid conduit at the jet
receiving portion to create a flow of fluid in the fluid conduit
from the intake portion to the ejection portion.
2. The fluid pump of claim 1, wherein vibration of the vibratable
membrane compresses and expands the volume of the pump chamber,
causing fluid to be drawn into and ejected from the pump
conduit.
3. The fluid pump of claim 1, wherein at least the actuating
portion is enclosed within a sealed container.
4. The fluid pump of claim 1, wherein the vibratable membrane and
the actuating portion are surrounded by a sealed container, wherein
the vibratable membrane is an airtight barrier between first and
second portions of the sealed container such that the first portion
of the sealed container isolated on a first side of the vibratable
membrane forms the pump chamber and the second portion of the
sealed container isolated on a second side of the vibratable
membrane forms a second pump chamber.
5. The fluid pump of claim 3, wherein a second pump conduit is in
fluid communication with the second pump chamber and the fluid
conduit, and wherein vibration of the membrane draws fluid into and
ejects fluid out of the second pump conduit to create a second net
momentum of fluid in the predetermined direction, wherein the fluid
conduit includes a second jet receiving portion between the intake
portion and the ejection portion wherein the second net momentum of
fluid is communicated to the fluid conduit at the second jet
receiving portion to create a flow of fluid in the fluid conduit
from the intake portion to the ejection portion.
6. The fluid pump of claim 5, wherein jet receiving portion and the
second jet receiving are generally located at the same fluid flow
point in the fluid tube.
7. The fluid pump of claim 5, wherein the jet receiving portion and
the second jet receiving portion are located successively along
fluid flow within the fluid conduit.
8. The fluid pump of claim 7, wherein the jet receiving portion and
the second jet receiving portion are spaced such that the net
momentum and the second net momentum create a peristaltic motion of
fluid within the fluid conduit.
9. The fluid pump of claim 1, wherein the actuating portion
comprises an electromagnetic device that causes vibration of the
membrane.
10. The fluid pump of claim 1, wherein the intake portion extracts
fluid from a mainstream flow of fluid for measurement of one or
more characteristics of the extracted fluid.
11. The fluid pump of claim 10, wherein the mainstream flow of
fluid is part of a breathing circuit such that the mainstream flow
of fluid comprises exhaled breath from a living organism.
12. The fluid pump of claim 11, wherein at least one of the one or
more characteristics of the extracted fluid comprises a
concentration of carbon dioxide within the extracted fluid.
13. The fluid pump of claim 11, wherein at least one of the one or
more characteristics of the extracted fluid comprises a
concentration of oxygen within the extracted fluid.
14. The fluid pump of claim 1, wherein the flow of fluid in the
fluid conduit extracts fluid having a first temperature from the
source of fluid at the intake portion and expels the extracted
fluid from the ejection portion onto one or more objects having a
second temperature, the first temperature being less than the
second temperature such that the fluid expelled from the ejection
portion of the fluid conduit cools the one or more objects.
15. A method of pumping fluid through a fluid conduit, the fluid
conduit having an intake portion, an ejection portion and a jet
receiving portion therebetween, the intake portion arranged to be
placed in communication with a source of fluid, wherein a pump
conduit is in fluid communication with the jet receiving portion of
the fluid conduit, the pump conduit being in fluid communication
with a pump chamber coupled to a vibratable membrane, the method
comprising: vibrating the vibratable membrane so as to alternately
draw fluid into and eject fluid from the pump conduit to create a
net momentum of fluid in a predetermined direction, wherein the net
momentum of fluid is communicated to the fluid conduit at the jet
receiving portion to create a flow of fluid in the fluid conduit
from the intake portion to the ejection portion.
16. The method of claim 15, wherein vibration of the vibratable
membrane compresses and expands the volume of the pump chamber,
causing fluid to be drawn into and ejected from the pump
conduit.
17. The method of claim 15, wherein the vibratable membrane is
vibrated using an actuating portion.
18. The method of claim 17, wherein at least the actuating portion
is enclosed within a sealed container.
19. The method of claim 17, wherein the actuating portion comprises
an electromagnetic device that vibrates the vibratable
membrane.
20. The method of claim 19, wherein the vibratable membrane and the
actuating portion are surrounded by a sealed container, wherein the
vibratable membrane is an airtight barrier between first and second
portions of the sealed container such that the first portion of the
sealed container isolated on a first side of the vibratable
membrane forms the pump chamber and the second portion of the
sealed container isolated on a second side of the vibratable
membrane forms a second pump chamber.
21. The method of claim 20, wherein a second pump conduit is in
fluid communication with the second pump chamber and the fluid
conduit, and wherein vibration of the membrane draws fluid into and
ejects fluid out of the second pump conduit to create a second net
momentum of fluid in the predetermined direction, wherein the fluid
conduit includes a second jet receiving portion between the intake
portion and the ejection portion wherein the second net momentum of
fluid is communicated to the fluid conduit at the second jet
receiving portion to create a flow of fluid in the fluid conduit
from the intake portion to the ejection portion.
22. The method of claim 21, wherein jet receiving portion and the
second jet receiving are generally located at the same fluid flow
point in the fluid tube.
23. The method of claim 21, wherein the jet receiving portion and
the second jet receiving portion are located successively along
fluid flow within the fluid conduit.
24. The method of claim 23, wherein the jet receiving portion and
the second jet receiving portion are spaced such that the net
momentum and the second net momentum create a peristaltic motion of
fluid within the fluid conduit.
25. The method of claim 15, wherein the intake portion extracts
fluid from a mainstream flow of fluid for measurement of one or
more characteristics of the extracted fluid.
26. The method of claim 25, wherein the mainstream flow of fluid is
part of a breathing circuit such that the mainstream flow of fluid
comprises exhaled breath from a living organism.
27. The method of claim 26, wherein at least one of the one or more
characteristics of the extracted fluid comprises a concentration of
carbon dioxide within the extracted fluid.
28. The method of claim 26, wherein at least one of the one or more
characteristics of the extracted fluid comprises a concentration of
oxygen within the extracted fluid.
29. The method of claim 15, wherein the flow of fluid in the fluid
conduit extracts fluid having a first temperature from the source
of fluid at the intake portion and expels the extracted fluid from
the ejection portion onto one or more objects having a second
temperature, the first temperature being less than the second
temperature such that the fluid expelled from the ejection portion
of the fluid conduit cools the one or more objects.
30. A fluid pump comprising: a fluid conduit having an intake
portion, an ejection portion, and a jet receiving portion
therebetween, the intake portion arranged to be placed in
communication with a source of fluid; and means for creating a net
momentum of fluid in a predetermined direction, wherein the net
momentum of fluid is communicated to the fluid conduit at the jet
receiving portion to create a flow of fluid in the fluid conduit
from the intake portion to the ejection portion.
31. The fluid pump of claim 30, wherein the means for creating a
net momentum of fluid in the predetermined direction comprises a
vibratable membrane, a pump chamber coupled to the vibratable
membrane, a pump conduit and means for vibrating the vibratable
membrane, such that vibration of the membrane draws fluid into the
pump conduit and ejects fluid from the pump conduit to create the
net momentum of fluid in the predetermined direction
32. The fluid pump of claim 31, wherein the vibratable membrane and
means for vibrating are surrounded by a sealed container, wherein
the vibratable membrane is an airtight barrier between first and
second portions of the sealed container such that the first portion
of the sealed container isolated on a first side of the vibratable
membrane forms the pump chamber and the second portion of the
sealed container isolated on a second side of the vibratable
membrane forms a second pump chamber.
33. The fluid pump of claim 32, wherein a second pump conduit is in
fluid communication with the second pump chamber and the fluid
conduit, and wherein vibration of the membrane draws fluid into and
ejects fluid out of the second pump conduit to create a second net
momentum of fluid in the predetermined direction, wherein the fluid
conduit includes a second jet receiving portion between the intake
portion and the ejection portion wherein the second net momentum of
fluid is communicated to the fluid conduit at the second jet
receiving portion to create a flow of fluid in the fluid conduit
from the intake portion to the ejection portion.
34. The fluid pump of claim 33, wherein jet receiving portion and
the second jet receiving are generally located at the same fluid
flow point in the fluid tube.
35. The fluid pump of claim 33, wherein the jet receiving portion
and the second jet receiving portion are located successively along
fluid flow within the fluid conduit.
36. The fluid pump of claim 35, wherein the jet receiving portion
and the second jet receiving portion are spaced such that the net
momentum and the second net momentum create a peristaltic motion of
fluid within the fluid conduit.
37. The fluid pump of claim 30, wherein the means for vibrating
includes an electromagnetic device that causes vibration of the
membrane.
38. The fluid pump of claim 30, wherein the intake portion extracts
fluid from a mainstream flow of fluid for measurement of one or
more characteristics of the extracted fluid.
39. The fluid pump of claim 38, wherein the mainstream flow of
fluid is part of a breathing circuit such that the mainstream flow
of fluid comprises exhaled breath from a living organism.
40. The fluid pump of claim 39, wherein at least one of the one or
more characteristics of the extracted fluid comprises a
concentration of carbon dioxide within the extracted fluid.
41. The fluid pump of claim 39, wherein at least one of the one or
more characteristics of the extracted fluid comprises a
concentration of oxygen within the extracted fluid.
42. The fluid pump of claim 30, wherein the flow of fluid in the
fluid conduit extracts fluid having a first temperature from the
source of fluid at the intake portion and expels the extracted
fluid from the ejection portion onto one or more objects having a
second temperature, the first temperature being less than the
second temperature such that the fluid expelled from the ejection
portion of the fluid conduit cools the one or more objects.
Description
[0001] This application claims priority to U.S. patent application
No. 61/100,413 filed 22 Sep. 26, 2008, the entire contents of which
are incorporated herein by reference.
[0002] The present invention pertains to a synthetic jet eductor
pump.
[0003] Conventional pumps often utilize numerous complex moving
parts to move fluid from one place to another. These pumps often
have high manufacturing and maintenance costs due to their numerous
components and associated mechanical complexity. In certain
delicate uses such as, for example, medical applications,
conventional pumps may be even more costly. As such, low-complexity
pump designs may be desirable.
[0004] In some applications, lower complexity pumps may include
injector or aspirator-type pumps, wherein a stationary jet of
motive fluid is used to pump a second fluid from one place to
another. However, these types of aspirator-type pumps carry the
disadvantage of mingling the fluid to be pumped with the motive
fluid. This is especially disadvantageous when the fluid to be
pumped is chemically reactive, contaminated, etc. Additionally,
these aspirator-type pumps require a constant supply of motive
fluid, which can add to operating costs. Furthermore, in some
instances, difficulty may arise when disposing of the motive fluid,
especially once it has mingled with the fluid to be pumped.
[0005] These and other problems exist.
[0006] The invention solving these and other problems in the art
provides a low-cost, reliable fluid pump that provides a motive
force within a fluid conduit without the need for a separate flow
of motive fluid.
[0007] In some embodiments, the invention provides a synthetic jet
eductor pump that includes a synthetic jet coupled into a tube or
other conduit where fluid to be pumped is or will be present (a
"fluid tube" or "fluid conduit"), wherein a pumping action through
the fluid tube is established due to the net momentum injected by
the synthetic jet. The synthetic jet may include a loudspeaker
device that is coupled to a pump conduit via a chamber. The
loudspeaker may include a vibratable membrane and an actuating
portion. In some embodiments, the membrane may be made to vibrate
using electromagnetic methods. In some embodiments, other methods
may be used to cause the membrane to vibrate.
[0008] Vibration of the membrane expands and contracts the volume
of the chamber, therefore causing air or other fluid to be
alternately drawn into and expelled out of an outlet portion of the
pump conduit. At intake, air (or other fluid) is drawn into the
pump conduit from all directions. However, when the air (or other
fluid) is pushed out again, flow separation results in the
formation of a directed jet. This jet is constituted from the fluid
surrounding the outlet portion of the pump conduit and on average
no (mass of) fluid is thus injected into the surroundings of the
outlet of the pump conduit. However, due to the difference between
intake and outflow (i.e., fluid drawn in from a broadening or
larger region of space, and ejected outwards into a relatively
narrow stream of space), the synthetic jet actuator does provide a
net "injection" of momentum into the surroundings of the outlet of
the pump conduit.
[0009] The synthetic jet actuator may be used to establish a net
momentum and thus a pumping action on a fluid through a fluid
conduit. The fluid conduit may include an intake portion, an
ejection portion, and at least one jet receiving portion. The jet
receiving portion of a fluid conduit according to various
embodiments of the invention includes the area of the interior of
the fluid conduit wherein a directed jet of fluid introduces a net
momentum into the fluid conduit in a particular direction. The jet
of fluid that causes a net momentum from a synthetic jet is
constituted from fluid surrounding the pump conduit, thus no
secondary fluid flow generated by a separate pump is needed. The
outlet portion of the pump conduit of the synthetic jet actuator is
coupled in parallel in a fluid conduit at the jet receiving portion
of the fluid conduit.
[0010] The net momentum flux injected by the synthetic jet
establishes a pumping action through the fluid conduit. As such,
when the intake portion of a fluid conduit is placed in
communication with a source of fluid, the net momentum communicated
to the fluid conduit at the jet receiving portion causes a flow of
through the fluid conduit such that fluid is drawn into the intake
portion of the fluid conduit and through the fluid conduit towards
the ejection portion of the fluid conduit. The concept can be
scaled to different sizes, as necessary.
[0011] In some embodiments, the loudspeaker of a synthetic jet
actuator may be positioned in a closed box or sealed container so
as to minimize sound radiation to the exterior.
[0012] In some embodiments, a dipole synthetic jet actuator can be
employed. This may minimize both the sound radiated to the exterior
and the interior of the fluid conduit. A dipole synthetic jet
eductor pump according to various embodiments of the invention may
include a loudspeaker that is positioned within a box or sealed
container such that the membrane of the loudspeaker creates two
chambers within the box. The membrane creates an airtight barrier
between the two chambers such that the first chamber is isolated on
a first side of the membrane and forms a first pump chamber.
Likewise, a second chamber is isolated on a second side of the
membrane and forms a second pump chamber. Additionally, a pump
conduit is in fluid communication with each of the two chambers.
Thus, the movement of the membrane alternately compresses and
expands the two chambers. Therefore, the pump conduits alternately
supply synthetic jets to a fluid conduit at jet receiving portions
within the fluid conduit, thereby communicating first and second
net momentums to the fluid conduit, resulting in a pumping action
through the fluid conduit from the intake portion to the ejection
portion.
[0013] In some embodiments, the outlets of pump conduits (and
therefore the jet receiving portions of the corresponding fluid
conduit) may be located generally at the same point of fluid flow
in the fluid conduit. In some embodiments, the two pump conduit
outlets (and therefore the jet receiving portions of the
corresponding fluid conduit) of a dipole synthetic jet actuator may
be coupled into a fluid tube successively along the fluid flow. Due
to the fact that the synthetic jets, emerging from the two outlets
are in anti-phase, this can establish, with proper distance between
the outlets, a `peristaltic motion` through the fluid tube, which
may enhance the pumping action. Furthermore, the distance between
the outlets can also be chosen such that acoustic waves in the tube
are optimally suppressed.
[0014] In some embodiments, multiple synthetic jet actuators may be
configured successively in a fluid conduit/tube. These actuators
may each be either of the normal monopole type or of the dipole
type. In some embodiments, the phase difference between the
successive synthetic jets may be adjusted as desired. For example,
this phase difference may be tuned such that an optimal performance
in pumping action (e.g., peristaltic action), low noise generation,
and/or other results are obtained.
[0015] Synthetic jet eductor pumps according to various embodiments
of the invention may be used in various applications, including any
application wherein a pumping action created by a net momentum of
fluid through a conduit is needed or desired. In some instances,
for example, a synthetic jet eductor pump according to various
embodiments of the invention may be used in conjunction with
sidestream fluid analysis. Sidestream fluid analysis typically
refers to transporting fluid away from a mainstream flow of fluid
and measuring one or more characteristics of the fluid in the
transported sample at location remote from the mainstream flow of
fluid. For example, the mainstream flow of fluid may be the exhaled
breath of a patient hooked up to a respirator. A diverter/adaptor
may remove a portion of the gas traveling through the main airway
of the respirator and transport that gas through a fluid conduit.
The motive force used to remove the gas from the mainstream flow of
fluid and through the fluid conduit may be a synthetic jet eductor
pump according to various embodiments of the invention.
[0016] In some instances, a synthetic jet eductor pump according to
various embodiments of the invention may be utilized in cooling
applications, such as, for example, the cooling of electronics.
This may be advantageous over other cooling devices in that air for
cooling can be drawn from an area remote from the objects to be
cooled, such that the air for cooling has a lower temperature than
the objects or the air surrounding the objects.
[0017] Other uses of synthetic jet eductor pumps according to the
invention will be evident to those having ordinary skill in the
art, including those for pumping various fluids in varying
applications. Furthermore, the various systems and apparatuses
described herein may operate using various system configurations as
appreciated by those having ordinary skill in the art. Accordingly,
some embodiments may utilize more or less components than those
described herein. In some embodiments, components may be duplicated
and/or oriented differently.
[0018] These and other objects, features, and characteristics of
the present invention, as well as the methods of operation and
functions of the related elements of structure and the combination
of parts and economies of manufacture, will become more apparent
upon consideration of the following description and the appended
claims with reference to the accompanying drawings, all of which
form a part of this specification, wherein like reference numerals
designate corresponding parts in the various figures. It is to be
expressly understood, however, that the drawings are for the
purpose of illustration and description only and are not intended
as a definition of the limits of the invention. As used in the
specification and in the claims, the singular form of "a", "an",
and "the" include plural referents unless the context clearly
dictates otherwise.
[0019] FIG. 1 is an example of a synthetic jet according to various
embodiments of the invention.
[0020] FIGS. 2A and 2B are examples of synthetic jet eductor pumps
according to various embodiments of the invention.
[0021] FIG. 3 is an example of a synthetic jet eductor pump having
a sealed loudspeaker, according to various embodiments of the
invention.
[0022] FIG. 4 is an example of a dipole synthetic jet eductor pump
according to various embodiments of the invention.
[0023] FIG. 5 is an example of a dipole synthetic jet eductor pump
according to various embodiments of the invention.
[0024] FIG. 6 is an example of a sidestream analysis system using a
synthetic jet eductor pump, according to various embodiments of the
invention.
[0025] FIG. 7 is an example of a sensor assembly for a sidestream
analysis system using a synthetic jet eductor pump, according to
various embodiments of the invention.
[0026] FIG. 8 is an example of a cooling system using a synthetic
jet eductor pump according to various embodiments of the
invention.
[0027] One aspect of the invention provides a synthetic jet eductor
pump that includes a synthetic jet coupled into a tube or other
conduit where fluid to be pumped is or will be present (a "fluid
tube" or "fluid conduit"), wherein a pumping action through the
fluid tube is established due to the net momentum injected by the
synthetic jet.
[0028] FIG. 1 illustrates a synthetic jet 100 according to some
embodiments of the invention. The synthetic jet 100 may include a
loudspeaker device 101 that is coupled to a pump conduit 103 via a
chamber 105. The loudspeaker includes a vibratable membrane 107 and
an actuating portion 109. In some embodiments, membrane 107 may be
made to vibrate using electromagnetic methods. For example, in some
embodiments, membrane 107 may include a wire coil, or other
apparatus that creates a magnetic field when energized, attached
thereto, while actuating portion 109 may include a stationary
magnet. When the wire coil of membrane 107 is energized (e.g., by
running an electric current through the wire coil), a magnetic
field is created, which interacts with the stationary magnet of
actuating portion 109. This interaction attracts and/or repulses
the wire coil attached to membrane 107, thus causing membrane 107
to move. Thus, membrane 107 may be caused to vibrate by rapidly
energizing and de-energizing the wire coil. In some embodiments, a
magnet may be attached to membrane 107, while a wire coil is
attached to actuating portion 109, wherein energizing the wire coil
of actuating portion 109 creates a magnetic field that causes the
magnet and thus membrane 107 to vibrate. In some embodiments, other
methods may be used to cause membrane 107 to vibrate, such as, for
example, one or more piezotransducers that convert electrical
energy onto mechanical energy for vibrating membrane 107. Other
methods of vibrating membrane 107 may also be used, such as, for
example, electrostatic or other methods.
[0029] Vibration of membrane 107 expands and contracts the volume
of the chamber, therefore causing air or other fluid to be
alternately drawn into and expelled out of an outlet portion of
pump conduit 103. As shown by the flow arrows in FIG. 1, at intake,
air (or other fluid) is drawn into pump conduit 103 from all
directions. However, when the air (or other fluid) is pushed out
again, flow separation results in the formation of a directed jet.
This jet is constituted from the fluid surrounding the outlet
portion of pump conduit 103, and on average no (mass of) fluid is
thus injected into the surroundings of the outlet of pump conduit
103. However, due to the difference between intake and outflow
(i.e., fluid drawn in from a broadening or larger region of space,
and ejected outwards into a relatively narrow stream of space), the
actuator does provide a net `injection` of momentum into the
surroundings of the outlet of pump conduit 103.
[0030] FIGS. 2A and 2B illustrate examples of synthetic jet eductor
pumps 200a and 200b according to various embodiments of the
invention. In each of jet eductor pumps 200a and 200b, synthetic
jet actuator 100 is used to establish a net momentum and thus a
pumping action on a fluid through fluid conduits 201a and 201b,
respectively. Fluid conduits 201a and 201b each include intake
portions (203a and 203b, respectively), ejection portions (205a and
205b, respectively), and at least one jet receiving portion (207a
and 207b, respectively). The jet receiving portion of a fluid
conduit, according to various embodiments of the invention,
includes the area of the interior of the fluid conduit wherein a
directed jet of fluid introduces a net momentum into the fluid
conduit in a particular direction. The jet of fluid that causes a
net momentum from a synthetic jet is constituted from fluid
surrounding the pump conduit, thus no secondary fluid flow
generated by a separate pump is needed.
[0031] In both synthetic jet eductor pump 200a and 200b, the outlet
portion of pump conduit 103 of synthetic jet actuator 100 is
coupled in parallel in a fluid conduit (i.e., 201a or 201b) at the
jet receiving portion of the fluid conduit (i.e., 207a and 207b).
In FIG. 2A, the synthetic jet actuator is coupled in a bend of
fluid conduit 201a such that jet receiving portion 207a occurs in a
part of fluid conduit 201a so as to communicate the net momentum
caused by the directed jet from synthetic jet actuator 100 to fluid
conduit 201a in the direction of ejection portion 205a. In FIG. 2B,
pump conduit 103 of the synthetic jet actuator itself is coupled
through the side of fluid conduit 201b and subsequently bent such
that jet receiving portion 207b occurs in a part of fluid conduit
201b so as to communicate the net momentum caused by the directed
jet from synthetic jet actuator 100 to fluid conduit 201b in the
direction of ejection portion 205b. In both implementations, the
net momentum flux injected by a synthetic jet establishes a pumping
action through the fluid conduit (i.e., fluid conduits 201a or
201b) as indicated in FIGS. 2A and 2B. As such, when the intake
portion of a fluid conduit (203a or 203b) is placed in
communication with a source of fluid, the net momentum communicated
to the fluid conduit at the jet receiving portion causes flow
through the fluid conduit such that fluid is drawn into the intake
portion of the fluid conduit and through the fluid conduit towards
the ejection portion of the fluid conduit (205a or 205b). The
concept can be scaled to different sizes, as necessary.
[0032] In some embodiments, the fluid conduit through which a fluid
is to be pumped (e.g., 201a, 201b) may include an acoustical lining
on the interior of the conduit so as to dampen sound. Furthermore,
the inlet portion (e.g., 203a, 203b) and/or ejection portion (e.g.,
205a, 205b) of a fluid conduit used in various embodiments of the
invention may be constructed so as to avoid flow separation during
intake and/or ejection of fluid through the fluid conduit. For
example, a gradually converging or narrowed inlet portion and/or
ejection portion, may avoid flow separation at these orifices.
Furthermore, rounded edges at these orifices (inlet portions and
ejection portions) may aid in avoiding flow separation. These
measures further serve to discourage sound within a fluid conduit.
Such sound may assist in causing flow separation, and thus jetting
at the inlets and outlets of the fluid conduit, which may be
undesirable.
[0033] In some embodiments, the loudspeaker of a synthetic jet
actuator may be positioned in a closed box or sealed container so
as to minimize sound radiation to the exterior. FIG. 3 illustrates
an example of a synthetic jet eductor pump 300 according to various
embodiments of the invention, wherein the loudspeaker 101 of
synthetic jet actuator 100 is positioned in a closed box 301. Jet
eductor pump 300 also includes fluid conduit 201 having intake
portion 203, ejection portion 205, and jet receiving portion
207.
[0034] In some embodiments, a dipole synthetic jet actuator can be
employed. This may minimize the sound radiated to the exterior and
the interior of the fluid conduit and/or may provide other
features. FIG. 4 illustrates an example of a dipole synthetic jet
eductor pump 400 according to various embodiments of the invention,
wherein loudspeaker 101 is positioned within box or sealed
container 401 such that membrane 107 creates two chambers 405a and
405b, within box 401. Membrane 107 creates an airtight barrier
between chamber 405a and 405b such that chamber 405a is isolated on
a first side of membrane 107 and forms a first pump chamber.
Likewise, chamber 405b is isolated on a second side of membrane 107
and forms a second pump chamber.
[0035] Pump conduits 403a and 403b are in fluid communication with
chambers 405a and 405b, respectively. Thus, the movement of
membrane 107 alternately compresses and expands chambers 405a and
405b (and thus the fluid therein). Therefore, pump conduits 403a
and 403b alternately supply synthetic jets to fluid conduit 407 at
jet receiving portions 413 and 415, thereby communicating first and
second net momentums to fluid conduit 407, resulting in a pumping
action through fluid conduit 407 from intake portion 409 to
ejection portion 411.
[0036] Whereas, in some embodiments, the outlets of pump conduits
(and therefore the jet receiving portions of the corresponding
fluid conduit) may be located generally at the same point of fluid
flow in the fluid conduit (see e.g., FIG. 4), in some embodiments,
the two pump conduit outlets (and therefore the jet receiving
portions of the corresponding fluid conduit) of a dipole synthetic
jet actuator may be coupled into a fluid tube successively along
the fluid flow. FIG. 5 illustrates an example of a dipole synthetic
jet eductor pump 501 according to various embodiments of the
invention, wherein the outlets of two pump conduit outlets (and
therefore jet receiving portions 513 and 515 of fluid conduit 507)
are located successively along fluid flow within a fluid conduit.
Synthetic jet eductor pump 501 includes loudspeaker 101 that is
positioned in box or sealed container 501 such that membrane 107
creates two chambers 505a and 505b in box 501. Pump conduits 503a
and 503b are coupled with chambers 505a and 505b, respectively.
Therefore, pump conduits 503a and 503b alternately supply synthetic
jets to fluid conduit 507, thereby communicating first and second
net momentums to fluid conduit 507 at jet receiving portions 513
and 515, resulting in a pumping action through fluid conduit 507
from intake portion 509 to ejection portion 511. Due to the fact
that the synthetic jets, emerging from the two outlets of 503a and
503b, are in anti-phase, this can establish, with proper distance
between the outlets, a "peristaltic motion" through fluid tube 507,
which may enhance the pumping action. Furthermore, the distance
between the outlets can also be chosen such that acoustic waves in
the tube are optimally suppressed. For example, if the outlets (and
thus the jet receiving portions) are in antiphase, the distance
between them would be n*.lamda.. When the outlets are in phase, the
distance between them would be (n+0.5)*.lamda.. Here, n=0, 1, 2, .
. . etc. and .lamda. is the wavelength of the sound related to the
"f" of the sound according to c=.lamda.*f, with "c" being the speed
of sound. Here, the frequency f may be the frequency with which the
synthetic jet actuator is driven: f=f0. However, given that
acoustic annoyance is often rather due to higher harmonics, the
frequency f considered in the determining the optimal spacing of
synthetic jet outlets may then be 2f0, 3f0, and so on.]
[0037] In some embodiments, multiple synthetic jet actuators may be
configured successively in a fluid conduit/tube. These actuators
may each be either of the normal monopole type or of the dipole
type. In some embodiments, the phase difference between the
successive synthetic jets may be adjusted as desired. For example,
this phase difference may be tuned such that an optimal performance
in pumping action (e.g., peristaltic action), low noise generation,
and/or other features are obtained.
[0038] Synthetic jet eductor pumps according to various embodiments
of the invention may be used in various applications, including any
application wherein a pumping action created by a net momentum of
fluid through a conduit is needed or desired. In some instances,
for example, a synthetic jet eductor pump according to various
embodiments of the invention may be used in conjunction with
sidestream fluid analysis. Sidestream fluid analysis typically
involves transporting fluid away from a mainstream flow of fluid
and measuring one or more characteristics of the fluid in the
transported sample at location remote from the mainstream flow of
fluid. For example, the mainstream flow of fluid may be the exhaled
breath of a patient hooked up to a respirator. A diverter/adaptor
may remove a portion of the gas traveling through the main airway
of the respirator and transport that gas through the fluid conduit
of the synthetic jet eductor pump. The motive force used to remove
the gas from the mainstream flow of fluid and through the fluid
conduit may be a synthetic jet eductor pump according to various
embodiments of the invention.
[0039] FIG. 6 illustrates an example of a sidestream fluid analysis
system 600 that utilizes a synthetic jet eductor pump according to
various embodiments of the invention. System 600 may include a main
flow of fluid 601. System 600 may also include a synthetic jet 601
that communicates a net momentum to fluid conduit 605 at jet
receiving portion 613, which in turn creates a motive force/pumping
action through fluid conduit 605. The pumping action created by
synthetic jet 603 through fluid conduit 605 may extract fluid from
main flow of fluid 601 at an intake portion 609 of fluid conduit
605. The extracted fluid may then be carried through fluid conduit
605 and through analysis unit 607, wherein one or more
characteristics of the fluid may be measured. For example, in some
embodiments, capnography (i.e., the measurement of carbon dioxide
[CO.sub.2] in a patient's breath) or oxygraphy (the measurement of
oxygen [O.sub.2] in patient's breath) may be performed on the
patient. In some embodiments, the measurement of nitrogen oxides
(NOx) may be a characteristic that is measured. Other
characteristics may also be measured. For more information relating
to sidestream analysis, see U.S. Patent Application Publication No.
20080041172 (U.S. patent application Ser. No. 11/771,268, entitled
"Sidestream Gas Sampling System with Closed Sample Circuit), which
is hereby incorporated by reference herein in its entirety. In some
embodiments, the analyzed fluid may be ejected from fluid conduit
605 at ejection portion 611. FIG. 7 illustrates a sensor assembly
for sidestream gas analysis according to various embodiments of the
invention.
[0040] In some instances, a synthetic jet eductor pump according to
various embodiments of the invention may be utilized in cooling
applications, such as, for example, the cooling of electronics or
in other cooling applications. FIG. 8 illustrates an example of a
synthetic jet 801 according to various embodiments of the invention
that is used to move fluid (e.g., air) through a fluid conduit 803
and onto one or more objects 805a-n (e.g., electronic components)
to cool one or more objects 805a-n. The net momentum established by
synthetic jet 801 at jet receiving portion 813 of fluid conduit 803
pumps air (or other fluid or gas) from a first area 807 into intake
portion 809, through fluid conduit 803, and out of ejection portion
811 onto one or more objects 805a-n. The air from first area 807
may be of a temperature lower than that of the one or more objects
805a-n (as electronic objects may become hot during operation),
thus exchanging heat with objects 805a-n and cooling objects
805a-n. In some instances, the use of a synthetic jet eductor pump
according to various embodiments of the invention as a cooling
system provides the advantage that the coolant air is not already
heated by the device to be cooled, as the coolant air supplied from
outside the device. In some embodiments, the first area 807 from
which the cooling fluid (e.g., air) is taken is generally thermally
isolated from where the fluid will be expelled once the cooling
fluid has come into contact with heated objects 805a-n. As such,
inlet 809 may be located at one side of a device exterior 815,
while an exit 817 from which the cooling fluid is vented after
exchanging heat with objects 805a-n, is located on an opposite side
of device exterior (or at least as far away as possible from inlet
portion 809.
[0041] The various systems and apparatuses described herein may
operate using various system configurations as appreciated by those
having ordinary skill in the art. Accordingly, some embodiments may
utilize more or less components than those described herein. In
some embodiments, components may be duplicated and/or oriented
differently.
[0042] Although the invention has been described in detail for the
purpose of illustration based on what is currently considered to be
the most practical and preferred embodiments, it is to be
understood that such detail is solely for that purpose and that the
invention is not limited to the disclosed embodiments, but, on the
contrary, is intended to cover modifications and equivalent
arrangements that are within the spirit and scope of the appended
claims. For example, it is to be understood that the present
invention contemplates that, to the extent possible, one or more
features of any embodiment can be combined with one or more
features of any other embodiment.
* * * * *