U.S. patent number 3,881,701 [Application Number 05/398,031] was granted by the patent office on 1975-05-06 for fluid mixer reactor.
This patent grant is currently assigned to Aerojet-General Corporation. Invention is credited to Robert C. Schindler, Leonard Schoenman.
United States Patent |
3,881,701 |
Schoenman , et al. |
May 6, 1975 |
FLUID MIXER REACTOR
Abstract
An improved fluid mixing device comprised of a plurality of
stacked, relatively thin plates having fluid passage means therein
to allow two or more fluids to pass therethrough and to be mixed
with each other yet at least one of the fluids, in the form of a
liquid, can be atomized to enhance the mixing action between the
two fluids. The device is constructed so that one or both fluids
can be used to cool the face plate of the device such as when the
latter is adjacent to a combustion chamber. Various embodiments of
the device are disclosed.
Inventors: |
Schoenman; Leonard (Citrus
Heights, CA), Schindler; Robert C. (Fair Oaks, CA) |
Assignee: |
Aerojet-General Corporation (El
Monte, CA)
|
Family
ID: |
23573719 |
Appl.
No.: |
05/398,031 |
Filed: |
September 17, 1973 |
Current U.S.
Class: |
239/403; 239/420;
239/422; 239/426; 366/101; 366/340; 422/224 |
Current CPC
Class: |
B01F
5/0604 (20130101); B01J 19/0093 (20130101); B01F
13/0059 (20130101); B01F 5/0256 (20130101) |
Current International
Class: |
B01J
19/00 (20060101); B01F 5/06 (20060101); B01f
005/02 (); B01f 005/18 () |
Field of
Search: |
;259/4,18,DIG.30,36,60
;138/38 ;48/18R,18H,18B ;23/252R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Jenkins; Robert W.
Attorney, Agent or Firm: McGannon; John L. Seka; J. Georg
Bell; John S.
Claims
We claim:
1. A fluid mixing device comprising: a plurality of relatively thin
plates arranged in a stack to form a platelet assembly, one of the
plates being at the end of the stack and provided with an outlet
opening, the plate next adjacent to said end plate having an
elongated channel for receiving a first fluid and for placing the
latter in heat exchange relationship to the end plate, said
assembly having first passage means coupled with the channel for
directing the first fluid from the latter to said opening, a second
passage means for directing a second fluid into mixing relationship
to the first fluid, and means defined by said passage means and
employing the kinetic energy of the flowing fluid for atomizing at
least one of the fluids as it flows through said assembly and prior
to its being mixed with the other fluid.
2. A device as set forth in claim 1, wherein said end plate has a
second opening adjacent to said first opening, the second passage
means communicating with the second opening, said first passage
means and said second passage means defining respective first and
second passages oriented to cause the first and second fluids
leaving the assembly through the openings to traverse inclined
paths converging toward each other as the fluids flow away from
said end plate, whereby the fluids are mixed together exteriorly of
said assembly.
3. A device as set forth in claim 1, wherein said atomizing means
comprises a lip extending partially across the path of said one
fluid for engaging the same and for reducing the particle size
thereof as the fluid flows past the lip.
4. A device as set forth in claim 1, wherein the end plate has a
plurality of pairs of shaped outlet slots, there being a first
passage means and a second passage means for each pair of slots,
respectively, one of the slots of each pair communicating with the
corresponding first passage means and the other slot of each pair
communicating with the corresponding second passage means, the
slots of each pair being arranged to present a fluid spray
therefrom with the sprays being directed toward each other for
mixture at a zone exteriorly of the stack and between said pair of
slots.
5. A device as set forth in claim 1, wherein a first of said plates
of said assembly has a pair of opposed fluid passage therein
communicating with said outlet opening, and wherein the atomizing
means comprises means for directing one of the fluids through said
opposed fluid passages and toward and into impinging relationship
to each other to cause atomization of said one fluid prior to flow
thereof out of said assembly through said outlet opening.
6. A device as set forth in claim 1, wherein each of a pair of said
plates has a pair of opposed fluid passages therein communicating
with said outlet opening, and wherein the atomizing means comprises
means coupled with each pair of fluid passages, respectively, for
directing a respective fluid thereto whereby the fluid will pass
therethrough in a pair of streams and the streams will impinge upon
each other and atomize the fluid before the fluid passes out of the
assembly through said outlet opening.
7. A device as set forth in claim 6, wherein the zone of
impingement of the first fluid is disposed between the outlet
opening and the zone of impingement of the second fluid.
8. A device as set forth in claim 1, wherein said atomizing means
is defined by a swirl chamber.
9. A device as set forth in claim 1, wherein one of the plates has
means defining a swirl chamber, the latter forming a part of said
second passage means, whereby the second fluid entering the swirl
chamber will be caused to form a vortex which advances toward,
through and out of said outlet opening, said first passage means
including an outlet slot adjacent to said outlet opening and
disposed to permit said first fluid to leave said assembly and to
travel toward and into intersecting relationship to the vortex at a
location exteriorly of said assembly.
10. A device as set forth in claim 9, wherein said atomizing means
includes means defined by said plate adjacent to said end plate for
dividing the first fluid into two streams and for directing the two
streams into impingement with each other upstream of said outlet
slot to effect atomization of the first fluid, said dividing and
directing means being disposed to permit the first fluid to leave
the assembly through said outlet port along a path substantially
perpendicular to said end plate.
11. A device as set forth in claim 9, wherin said plate adjacent to
said end plate includes a fluid passage defining said first passage
means, said fluid passage being oriented in partial underlying
relationship to said end plate and in partial fluid communication
with said outlet slot to cause the first fluid to pass out of the
assembly through said outlet slot along an inclined path extending
toward the path of the vortex.
12. A device as set forth in claim 11, wherein said atomizing means
presents a projection defined by said end plate at one side of said
outlet slot in the inclined path of said first fluid to cause
atomization hereof.
13. A fluid mixing and atomizing device for forming an atomized
mixture of at least two fluids and for directing the fluids into a
surrounding atmosphere comprising a plurality of relatively thin
plates arranged in a stack to form a platelet assembly, a front of
the assembly being defined by an end plate having at least one
outlet opening, first fluid passage means for flowing a first fluid
through the stack and to the outlet opening, second fluid passage
means for flowing a second fluid through the stack into mixing
relationship with the first fluid, and means for atomizing at least
one of the fluids before its discharge from the stack and before
being mixed with the other fluid, the atomizing means comprising
means defined by at least one of the passage means for guiding the
fluid flow through such passage means so that such fluid is
atomized by virtue of its flow through the passage means.
14. A device according to claim 14 wherein the atomizing means
includes means for impinging two fluid streams flowing in the
stack.
15. A device according to claim 14 wherein the atomizing includes
means for causing at least one fluid stream in the stack to
abruptly change its flow direction to thereby atomize the fluid
such streams.
Description
This invention relates to improvements in the mixing of two
different fluids prior to utilization of the mixture and, more
particularly, to an improved fluid mixing device adapted to mix and
atomize fluids as well as to utilize one of a number of fluids for
cooling of the device itself.
The present invention is directed to a self-cooled device which
achieves the efficient atomization and mixing of two or more either
inert or reactive fluids. It accomplishes liquid stream atomization
and/or vapor phase mixing by hydraulic or mechanical means or a
combination of both. Mixing of two different fluids can be
concurrent with the atomization process or can follow atomization.
The mixer device can operate using a plurality of fluids and can be
designed to stage the mixing processes through controlled variation
in mass and mixture ratio and primary and secondary mixing and/or
reaction.
The fluid mixer device of this invention is comprised of a
plurality of thin plates which contain fluid-flow passages or
channels. Depending upon the composition of the fluids and the
platelet material, the plates can be joined in any one of a number
of different ways, such as by diffusion bonding, a brazing, or
adhesive. Platelet flow passages can be arranged so that a selected
fluid is routed to provide cooling of the mixer wall.
The device provides efficient mixing control by dividing the total
fluid flow into a very large number of precisely metered, very
small streams which are atomized prior to or during their mixing
with adjacent streams. All control of liquid flow, and indirectly
of liquid atomization, and mixing is by means of the laminate or
channel shape and depth. The fluid discharge from the device is
through apertures which are normal to an end plate of the device,
resulting in the outer face of the end plate being a continuous
member and the platelet bond lines not being exposed to the
reaction which follows mixing.
The quantity of outlets on the outer face of the device can be up
to several hundred per square inch, with each discharging a stream
of finely atomized fluid. Variation in the design of the device
allows these streams to consist of singular fluids or mixtures
resulting from impingement of unlike streams. These sprays of
atomized fluid can be directed to impinge on each other to acheive
a controlled primary mixing zone exteriorly or interiorly of the
device or, if directed axially, will experience secondary mixing by
virtue of their proximity.
The advantage of this device over other microelement platelet-type
mixers is that the following can be achieved without an increase in
stream size or flow per element:
(1) Fewer plates are needed, resulting in reduced structural
complexity and fewer bonded interfaces
(2) The outer face of the surface can be a single, continuous
member so that bond joints between the stacked plates of the device
need not be exposed.
(3) Atomization can be accomplished by stream impingement against
an integral splash plate, like-on-like stream impingement, or
like-on-unlike stream impingement. Since droplet size is not
totally dependent upon orifice size, larger, less easily plugged
passages and orifices can be utilized.
(4). Mixing is achieved by directed impingement or unlike sprays
following their atomization.
(5). The outer face of the device can be flat or can have a simple
or compound curvature. The face boundary can be polygonal or
circular.
The invention, in providing a means of atomizing and mixing
reactive or nonreactive fluids proximate to the surface of a flat
or curved plate, is suitable for use in the following applications
but is not limited thereto:
1. Propellant injection on both liquid and gaseous propellant
rocket engines.
2. Fluid injection to provide jet interaction for maneuverable
reentry bodies.
3. Liquid propellant injection for very low thrust liquid
propellant rocket engines.
4. Gas turbine propellant injection.
5. Chemical process mixing with both reactive and inert fluids.
6. Gas-liquid mixing for internal combustion engines.
7. Exhaust reactors.
8Chemical laser devices.
The primary object of this invention is to provide an improved
fluid mixer device of the type comprised of a plurality of stacked,
relatively thin plates arranged with certain fluid passages therein
so that the stack of plates can provide a fluid manifold and
distribution system, a coolant, system, and an atomizing and mixing
system tailored to accommodate two or more different fluids, such
as a fuel and atomizing agent, in an efficent manner.
Another object of this invention is to provide a device of the type
described wherein the mixing of two different fluids can occur
interiorly or exteriorly of the device during or after atomization
to provide flexibility in the use of the device yet the device is
highly efficient irrespective of its particular use.
A further object of this invention is to provide a fluid mixing
device of the aforesaid character wherein the device has a working
end face adapted to be placed near a reaction zone at which heat is
generated, the device having fluid passage means for directing a
fluid in proximity to the working face so that the fluid will be in
heat exchange relationship to such face and maintain the same in a
relatively cool condition to thereby minimize erosion of the face
due to the deteriorating effects of the heat generated thereto.
In the drawings:
FIG. 1 is a fragmentary, perspective view of a fluid mixing device
of this invention, showing the fluid passages therein and the
working end face thereof, arrows indicating the directions of flow
of fluids therethrough;
FIG. 2 is a cross-sectional view of the device of FIG. 1;
FIG. 2a is an enlarged, fragmentary, perspective view of the
embodiment of FIGS. 1 and 2, showing the way in which two fluid
stream impinge upon each other exteriorly of the device;
FIG. 3 is a view similar to FIG. 2 but showing another embodiment
of the device; and
FIGS. 4, 5 and 6 are additional embodiments of the device with each
of the latter embodiments utilizing a swirl chamber for generating
a fluid stream in the form of a vortex to enhance mixing of
fluids.
The various plates of device 10 are relatively thin and, while they
are shown as being of the same thickness, they could vary in
thickness from each other to suit specific requirements. A typical
range of thicknesses for such plates is 0.002 inch to 0.030 inch.
Since the plates are so thin, fluid channels or passages formed
therein are preferably formed by a conventional photoetching
technique to achieve the relatively fine dimensions of the
passages. Typical dimensions of such passages are of the order of
magnitude of the plate thicknesses.
Device 10 operates in a threefold manner, namely, it defines a
fluid manifold and distribution system; it defines a coolant system
wherein heat input from the region adjacent to end plate 12 is
conducted to one or several of the fluids passing through the
device; and it serves as an atomization and mixing system tailored
to accommodate selected fluids.
As shown in FIG. 1, plate 12 has a plurality of pairs of openings
26 and 28, each pair of openings being adjacent to each other and
arranged so that the fluid streams issuing therefrom will be in the
form of sprays directed toward each other in the manner shown in
FIG. 1. Plate 12 has a plurality of such pairs of openings 26 and
28. Typically, there are about 10 to 100 or so pairs of openings 26
and 28 per square inch of plate 12. For purposes of illustration,
each opening is trapezoidal in shape with the longer sides of the
openings being adjacent to each other so that the sides of one
opening diverge as the other opening is approached as shown in FIG.
1.
Plate 14 immediately adjacent to plate 12 has a number of fluid
channels 30 (FIG. 1) for delivering a fluid, such as a liquid, from
one side of device 10 across the device and along and in heat
exchange relationship to the inner surface of plate 12. In the
downstream end of each channel 30, plate 16 has a circular hole 32
placing the corresponding channel 30 in fluid communication with a
fluid passage 34 in plate 18 transverse to channel 30. Thus, fluid
passing from channel 30 into opening 32 and through passage 34 can
flow into a second opening 36 in plate 16, then up through an
opening 38 in plate 14 and out of device 10 through a corresponding
opening 26. Serpentive arrow 39 (FIG. 2) illustrates the path of
flow of fluid from a channel 30 to the corresponding opening 26.
Opening 38 in plate 14 is larger in size than opening 36 of plate
16 as shown in FIG. 2. Also, opening 26 is partially aligned with
opening 38 so that a portion 40 of plate 12 overhangs opening 38 to
present a lip or projection causing a fluid stream passing from
holes 36 and 38 to bent laterally as shown in FIG. 2. Furthermore,
portion 40 causes atomization of the fluid passing the same before
the fluid exits from device 10. The fluid exits from opening 26
along an inclined path as shown in FIG. 1, 2 and 3.
A second fluid directed toward each opening 28 flows upwardly
through aligned holes 44, 46, 48, 50 and 52 in plates 24, 22, 20,
18 and 16, respectively. Plate 14 has an enlarged hole 54 in fluid
communication with holes 52 and the corresponding opening 28
partially overlies on end of opening 54 to define an over-hanging
or projecting portion 56 which serves the same purpose as portion
40, namely to atomize the fluid before it exits from device 10. The
fluid leaving each opening 28 is directed along an inclined path
extending toward the fluid path extending away from the
corresponding opening 26. Serpentive arrow 57 (FIG. 2) represents
the flow of the second fluid through device 10 toward a
corresponding opening 28. While the second fluid is shown in FIG. 2
as coming from a channel 59 remote from end plate 12, it is
possible to form plate 14 so that the second fluid can be moved
into heat exchange relationship to plate 12 so that both fluids
operate to cool such plate.
The sprays issuing from each pair of opening 26 and 28 are denoted
by arrows 58 and 60 (FIG. 2a). The two sprays, both of which have
been previously atomized, mix together at a zone 62 substantially
midway between each pair of openings 26 and 28. After mixing
together, the mixture is ready for use, such as the fuel-oxidizer
source for a combustion chamber. Thus, device 10 allows atomization
of at least one of the fluids within the device, whereas, mixture
of the two fluids occurs exteriorly of the device. Device 10 is
adapted for use when direct impingement of liquids to be mixed
within device 10 is not desired, i.e., when an exothermic reaction
occurs upon impingement. Variations in the shapes of the holes in
plates 12 and 14 and the spacing of openings 26 and 28 allow the
spray character (spray shape and droplet size) -as well as the
position of impingement zone 62 to be varied.
The second embodiment of the fluid mixer device of this invention
is shown in FIG. 3 and is denoted by the numeral 110. Device 110
includes a stack of plates 112, 114, 116, 118, 120, 122 and 124,
such stack being arranged to operate in a manner to cause a direct
impinging mixing action of two fluid streams within the device
itself to cause atomization. Also, mixing of two different fluids
occurs within the device.
A first fluid enters device 110 along a pair of paths denoted by
arrows 126 and 128 and passes through respective holes 130 and 132
in plates 124 and 122, respectively. Holes 132 communicate with
respective fluid passages 134 in plate 120, passages 134 being
opposed to each other and terminating at a central opening 136
aligned with a shaped slot 138 in plate 118 and with shaped slots
140, 142 and 144 in plates 116, 114 and 112, respectively. Slots
140, 142 are of greater size than slot 138. Thus, within opening
136, the two streams of the first fluid flowing along the path
denoted by arrows 126 and 128 impinge upon each other to cause
atomization of the first fluid. The resulting mixture is expelled
through shaped slot 138 in plate 118.
Plate 116 has opposed fluid passages 146 formed therein which
communicate with transverse passages 148 in plate 114. A second
fluid entering passages 148 flows through the same to cool end
plate 112. The fluid then flows through respective, opposed
passages 146 in plate 116 along paths denoted by arrows 150 and
152. The two fluid streams exit from passages 146 and impinge
against each other at the center of slot 140 to cause atomization
of the second fluid. Plate 114 can be constructed so that passages
148 can be fed from the edge of device 110 or by passages from one
extremity thereof which penetrate through plates 116-124.
There is a mixing action within shaped slots 140, 142 and 144 of
the two different fluids, namely, the first fluid entering device
110 along paths 126 and 128 and the second fluid entering along
paths 150 and 152. The mixture occurs prior to exit from device
110. Before such mixing action, the first fluid will have been
atomized by impingement of the two streams thereof within opening
136.
FIG. 4 illustrates a third emobidment of the device of this
invention wherein mixing of two fluids is accomplished by a vortex
action. The device of this embodiment, denoted by the numeral 210,
is comprised of plates 212, 214, 216, 218, 220, 222 and 224
arranged in a stack. As before, plate 212 will have a number of
shaped slots or openings 226 per square inch. The vortex action
occurs within device 210 when a first fluid, flowing along a path
denoted by arrow 228, passes through a tangential port 230 at the
inner end of a fluid passage 236 in plate 220 and enters a swirl
chamber 232 also in plate 220. Plate 218 has a shaped slot 234
communicating with and defining the outlet of the swirl chamber.
The fluid entering the swirl chamber initially reaches fluid
passage 236 by way of openings 238 and 240 in plates 222 and 224,
respectively. Opening 240 is in fluid communication with a manifold
241 adapted to be coupled to a source of the first fluid.
Plate 216 contains a shaped slot 252 and a pair of fluid passages
242 and 244 which communicate with transverse passages 246 in plate
214. A second fluid flowing through passages 246 toward passages
242 and 244 will cool plate 212. The second fluid flows through
passages 242 and 244 along paths denoted by arrows 248 and 250 and
enters the vortex created by the first fluid because passages 242
and 244 are on opposite sides of the vortex. The two fluids are
thus mixed together within device 10 and flow out of the same in
vortex fashion through shaped slots 252, 254 and 266 in plates 216,
214 and 212, respectively. Fluid can be fed to passages 246 in
plate 214 from the edge of the stack or from a location thereon by
means of passages through plates 216-224. While the vortex action
within device 10 serves to mix the two different fluids with each
other, it also serves to atomize the second fluid.
FIG. 5 illustrates still another embodiment of a fluid mixer device
utilizing an internally generated vortex. In FIG. 5, the fluid
mixer device 310 is comprised of stacked plates 312, 314, 316, 318,
320, 322 and 324. A swirl chamber 326 is provided in plate 320 and
has an outlet denoted by a shaped slot 328 in plate 318. A first
fluid is supplied along a path 330 to the swirl chamber plate 320
after the fluid has passed through openings 332 and 334 in plate
324 and 322, respectively, and through a fluid passage 336 also in
plate 320. Passage 336 has an exit port 338 which is tangential to
swirl chamber 326 to create the vortex indicated by the spiral
arrow 340 leaving device 310 through shaped openings 342, 343 and
345 in plates 312, 314 and 316, respectively. As before, face plate
312 has a plurality of openings 342 per unit area inasmuch as the
relative sizes of the various openings and passages in each plate
are quite small.
A second fluid is fed through transverse passage 344 in plate 314,
there being a pair of passages 344 on each side of the vortex,
respectively. Passages 344 serve to permit the second fluid to cool
end plate 312 before mixing with the first fluid in the vortex. The
two streams of the second fluid which leaves each pair of passages
344 enters a passage 346 whereby impingement of the two streams
causes atomization of the second fluid before passing through
shaped slot 348 which causes the atomized second fluid to leave
device 310 in the form of a spray. Then the second fluid streams
denoted by arrows 349 are directed toward and intersect the vortex
of the first fluid to create a mixing action between the two
fluids.
FIG. 6 illustrates a modification of the embodiment of FIG. 5 in
that plate 314 is provided with only a single passage instead of a
pair of such passages on each side of the vortex, respectively. The
single passage, denoted by the numeral 344a , communicates with a
passage 346a , the latter being in fluid communication with slot
348a to cause atomization of the fluid flowing along a path denoted
by the numeral 350a. Atomization occurs because of the overhanging
portion 352a of plate 312 with respect to passage 346a . The second
fluid then flows along an inclined path as it leaves device 310
through each slot 348a and intersects the vortex of the first fluid
whereby the two fluids are mixed together. As before, the second
fluid passing through passages 344a cools end plate 312.
* * * * *