CA1070959A - Energy conversion device - Google Patents

Abstract

ENERGY CONVERSION DEVICE

Abstract of the Disclosure A vortex tube construction in which the cold and hot fluids are recirculated to the inlet and energy is extracted from or addad to the fluids either by heat exchange or by mechanical removal. This concept is adapted for other devices in which a flow of substantially homogeneous fluid is divided into separate flows at different energy levels.

Description

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Apparatus for the redistribution of energy within an initially homogeneous fluid, as in the Ranque-Hilsch vortex tube patent 1,952,281 or in Foa 31361,336 has been used in heating or refrigeration by the direct use of the high energy fluid, for heating, or the low energy fluid for refrigerati~n and any kinetic energy is dissipated without being ukilized~
The present invention involves the recirculation o~ the fluid or fluids so as to recover the kinetic energy in the vortex and to return it to the vortex inlet with a minimum of loss.
The invention contemplates the removal of heat from the high energy level fluid and~or the addition of energy to the low energy level fluid during this recycling for performing cool-ing or heating functions. The energy in the fluids may also be utilized in power generation if such use is desired, the entire unit heing a self contained power unit.
The arrangement may be such that a transfer of energy from the cold to the hot side may occur for the purpose of addi-tional cooling at one side or additional heating at the other side or for the purpose of extracting heat from a low level heat source such as the atmosphere, the ocean or solar energy for the purpose o~ high temperature generation on the hot side.
The device contemplates a significantly high temperature of heat output on the hot side.
In accordance with one aspect of the present invention, there is provided a vortex tube system including. a casing having a fluid separation chamber in which a fluid introduced in a vortex is separated into hot and cold swirling streams, means for introducing the fluid into the chamber to produce a helical flow therein for causing the fluid separation; hot and cold conduits connected to said chamber to receive the hot and cold swirling stream~ of fluid, one of ~aid conduits including a return duct for the return of the fluid therein to the cham-

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ber downstream of said means, said return duct being connected to minimize kinetic energy loss from the swirling ~luid: and energy exchange means associated with saicl conduits for the removal of energy from the hot stream and addition of energy to the cold stream.
Other features and advantages of the invention will be apparent from the specification and claims and from the accompanying drawings which illustrate embodiments of the invention.
Figure 1 is a schematic view of a simplified internal recirculating system;
Figure 2 is a schematic view of a simplified external recirculating system, Figure 3 is a longitudinal sectional-view through a recirculating vortex tube:
Figure 4 is a transverse sectional view along line 4-4 of Figure 3:.
. Figure 5 is a partial longitudinal sectional view si~ilar to Figure 3 of a modification;
Figure 6 is a view showing one of the devices in use, Figure 7 is another view showing another use of thè
device, Figure 8 is a plan view of a modification, Figure 9 is a sectional view along line 9-9 of Figure 8: , Figure 10 is a sectional view of a detail, ~:
Figure 11 is a modified form of the device, Figure 12 is a fragmentary section through the nozzles of Figure 11: and Figure 13 is a view at right angles to the sectlon of Figure 12 .

Referring first to Fisure 1, the system is shown as

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an internal recirculating system in which the return system surrounds and is in concentric relation to the vortex tube.
The tube is made up of coaxial passages 2 and 4, the former being the cold tube and is smaller at the inlet end 6 than the hot tube 8. The latter extend~ to the right, Figure 1, and may be divergent in the direction of flow. These tubes are defined by the inner walls of cooperating annular bodies 10 and 12 locaked within and spaced from a casing 14 having an inner surface that defines, with the other surfaces of the bodies 10 and 12, annular cold and hot passages 16 and 18 for the return of the cold and hot fluids to the vortex inlet 20.
This inlet 20 is established by an axial spacing of the two annular bodies so as to define the inlet passage there-between. The adjacent end wall~ 22 and 24 of the kodies 10 and 12 may be parallel to one another, as shown, and the wa}ls may make a slight angle to a radial plane so that the inflow through the passage 20 ha a longitudinal component in an axial direction toward the hot tube~
The vortex ~or the tube is created by a nozzle 26 that is arranged tangentially to the periphery of the hot tube tube 8 to create a vortex at the inlet to this tube. The effect of this vortex is known. A hot fluid flow moves ko the right in the hot tube with a significant swirl, and cold air flows to the left in the cold tube also with a significant swirl. The nozzle 26 may be o* the type shown in the U. S.
patent to Sohre 3,804,335 ~or efficient operation of the device.
At the discharge ends of the vortex tubes the hot and cold fluids are directed through curved passages 28 and 30 at the cold and hot ends xespectively, these passages being defined between the koroidal ends of the casing 14 and the remote ends of the annular bodies 10 and 12, With proper con-figuration the hot and cold ends may have a temperature differ-~, .

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ence of as much a~ 180F with an inlet pressure of 100 p,s.i.~he temperature difference may reach several hundred degraes or even into the thou ands depending upon the mode of operation and the materials for containment of the fluids. Removal of some of the heat energy in the hot fluid is accomplished by surrounding the casing 14 with a heat exchange chamber 32 ~ub-stantially coextensive axiallylwith the hot annular kody 12.
With conven~ional heat exchange devices such as tubes or fins on the casing 14 at this point much of the heat energy in the hot fluid may be removed and utilized. Similarly with a heat exchange chamber 34 externally of the casing 14 in the cold area coextensive with the cold annular body 10, a warm fluid flowing through the chamber 34 may be cooled as for refrigera-tion use and at the same time the low energy level in the cool portion i9 raised since the cold fluid in the vortex system is heated and thus the reclaimed heat is added to the combined fluids reentering the vortex chamber.
A~ the device oper~tes, the hot and cold fluids in the recirculating passages may thus be respectively cooled and heated approximately to the same temperatures and are re-energized by the effect of the nozzle fluid and drawn through passage 20 and into the vortex again. The ]cinetic energy in the fluids is not lost since the swirl of the fluids is not lost in their return through the recirculating passages and only a small input of energy through the nozzle or impeller is necessary to maintain continuing and effective operation.
Fox the energy make-up through the noæzle a compressor 36 driven by power means 36a, pressurizes the fluid delivered throu~h a conduit 38 to the nozzle. This fluid may be drawn from the atmosphere if the device is operating on air through an inlet conduit 40 controlled by a valve 42 or rom the end of the hot tube through a conduit 44 controlled by valve 46, An ~ ' ~ 7~

outlet valve 47 permits exhaust of fluid ~rom the conduit 44 Alternatively or in addition, fluid ~rom the c~old end may be supplied to thQ compre~sor through a conduit 45 with a control valve 48 therein. A valve 50 permuts fluid in conduit 46 to exhaust if desired.
As an alternate to the internal recirculation of Figure 1 the vortex tube of Figure 2 may have an external re-circulation~ ~s shown, the hot tube 52 and cold tube 54 are coaxial as in Figure 1 and are interconnected at their adjacent ends by the vortex section 56. At their outer ends, the tubes are connected by connecting tubes 58 and 60 to a return duct 62.
This is preferably a tangential connection to mini~ize loss of kinetic energy. At a point adjacent the vortex section 56 is a recycling tube 64 by which the ~luid in the duct 62 is returned to the vortex section. A make-up nozzle 66 delivers fluid at high velocity into the tube ~4 for maintaining the necessary vortex in the vortex sec~ion 56. Energy is removed from the system by a heat exchanger 68 surrounding the hot portion 70 of the return duct which may be used to ~eat a fluid circulat-ing in the heat exchanger the hot fluid then being utilizedfor heating or other purposes.
Similarly the cold portion 72 of the return duct has a surrounding heat exchanger 72 that may be used for cooling a fluid in the heat exchanger, the cooled fluid then being used for refrigeration or other purposes where a cooling action is needed. In this way, heat eneryy is returned to the system at the same time providing for coolingO
Other arrangements for removal of energy from the system may be utiliæed. ~or example, as shown in Figure 3, the vortex tube 80 consists of two ducts, the hot duct 82 and the cold duct 84 extending coaxially in opposite direction~ from the vortex section 86. The hot duct is çreated by the inner :~D7~9~
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wall of an elongated torus 88 positioned in a cylindrical chamber 90 and spaced from the wall 92 of the chamber to define an annular return passaye 94 for the hot ~luids. ~he outer end of the tqrus 88 is spaced from the end wall 94 of the chamber to connect the duct 82 and the pa~sage 94 at this point, At the inner end af the torus the passage 94 discharges into the vortex section 86 past pre-swirl vanes 96, The cold duct 84 is created by another elongated torus 98, coaxial with the torus 88 and having a smaller inside diameter so that the cold duct is smaller in diameter than the hot duct. This torus 98 is spaced from the chamber wall to define a cold return duct 100, and pre-swirl vanes, at the vortex section end of the duct 100 impart a swirl to the returning cold fluid.
At the outer end of the torus 98 i.s positioned a rotor 102 defining a return passage 104, and this rotor may have tur~
bine blades 106 ther~on by which the rotor may ~e driven. The rotor is on a shaft 108 journalled in spaced bearings 110 and this shaft carries a compressor 112 for pressurizing fluid be-ing discharged into-the nozzle 114 in the vortex section 860 ~his fluid may be a portion of the hot ~luid delivered to the compressor through a duc~ 116 from a centrally located port 118 at the outer end of the hot duct4 A valve 1~0 may control the quantity o~ fluid reaching the compressor. Pressurized fluid ~rom the compressor discharge 122 is delivered through a duct 124 to the nozzle.
Where the operatin~ fluid is a gas, the nozzle 114, as shown in Figure 4 is a convergent diveryent, supersonic nozzle, as for example the conventional deLaval nozzle, and is positioned so that the discharge is tangential to the outer portion of the vortex chamber 86 which extends from the chamber wall inwardly between the inner ends of the toruses 88 and 98 and comminicates with the inner ends of the hot and cold ducts.

~L~709~9 Because of the character of the separation proce~s the inner end of the torus 98 may have an annular projection 128 at the inner diameter that in~tially directs fluid in the ohamber 86 toward the hot duct as shown by the arrows. Separation occuxs in this area and the cold ~tream moves int:o the cold duct, the hot stream continuing into the hot duct.
~ motor 130 is connected to the ~haft 108 for supple-menting ~he power of the turbine ~o opera~e the compressor.
If desired, a part o~ the cold fluid from the cold duct may be di~charged through the hollow shaft 108 into a duct 132 and thence to a place for use.
Heat energy is added to the system by heat exchanger 134 and removed by heat exchanger 136 on the outer surface o~
the wall 92 surrounding the cold and hot portions, respectively.
Heat exchanger 134 cool 9 a fluid flowing therethrough for use in refrigeration or for other cooliny purposes. ~eat exchanger heat a fluia flowing therethrough, thi~ fluid then being used for any desired heating purpose. The arrangement may be fur-ther improved by circulating a fluid through the hollow torus 88 in heat exchange relationship with the hot fluid in the hot d~ct.
The turbine rotor may be used as an impeller driven from an external ~ource either in starting the device or in increasing the velocity and whirl of the fluid. Under certain conditions this may replace the nozzle with the energy normally supplied by the nozzle being derived from the impeller. Ob-viously the ~enerator, not shown, normally driven by the tur-bine rotor, would become a motor for driving the rotor as an impeller.
A further arrangement for energy removal i5 shown in Fi~ure 5. In this showin~ the outer end of the hot tube 139 may have a turbine dis~c 140 with blades 14~. Thi9 turb;ne is driven by the hot 1uid and is mounted on a shaft 143 journalled ~'7~5~

in bearings 144 provided at the ond of the devlce. Th~ turbine serves to remove heat energy from the hot fluid and to convert ~hi~ into mechanical energy. A bleed valve 145 may be incor- ~
porated in the ~haft as shown. ~ovement of valve 145 to the left permits the escape of some of the hot: fluid for heating or other needs. The shaft may deliver power for any power requirement.
Similarly the cold end of the de!vice may have a recovery turbine 146 for extracting heat energy from the cold fluid thereby further lowering the temperature of this fluid, and converting the extracted energy into mechanical energy delivered by the shaft 147. A bleed valve 148 axially of the turbine 146 permits removal of some of the cold fluid for ex-ternal use. The valves 145 and 148 also serve to sustain the device by suitable control of the energy removal from the sys-tem. In this figure the hot and cold fluidq are returned through the conduits 149 to the vortex not shown~
In this arrangement, the eneryy input is through an inlet duct 150 to a nozzle 151 discharging into the vortex or fluid separation chamber 152 communicating with the hot tube 13~ and a cold outlet defined by the inwardly extending flange 153~ The cold outlet is smaller in diameter than the hot tube, as shown.
One use for a device of this character may be in air conditioning or heating of a building such as a home, of~ice building or the like~ As shown in Figure 6, an outer wall 154 of a building has an opening 155 therein to receive a device such as that shown in Figure 1. For heating, the device has its hot end 156 within the building and the cold end 157 out-side the building. As the device operates, the hot end of thedevice gives up heat by a circulation of air over the heat exchanger -158 surrounded by the radiating fins 159 and the cold ,.;~ . _ g_ ~ J

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end absorbs heat from the outside air through the heat exchanger 160 by a flow of outside air over the surrounding fins 162.
Thus the device functions much as a hsat pump but with a much simpler construction. Thi5 simpler con~truction i~ particularly advantageous when made in large and very large units.
For air conditioning the position is reversed with the cold end inside the room and the hot end outside the building. In thi~ position the device give~ up heat tv the outside air and removes heat from the air within the bu:ilding for cooling or air-conditioning the air. A suitable flange 164 permits mounting the device in either po~ition on the wall 150.
Another use may be in gas turbine systems. As shown in Figure 7, the air entering the compressor 170 driv~en by power means 170a is dixected over the cold end 172 oP the device 174 for lowering the air temperature and improving the compression cycle. Air discharging from the compressor is -circulated over the hot end 176 before reaching the combustion cbamber 178 on its way to the turbine 180.
Heat removed from the inlet ai~ to the compressor by the cold end of the device i~ added to the combustion air by the hot end thu~ the compressor inlet air temperature is lower-ed, to improve compressor efficiency and capacity, and the com-bustion chamber inlet temperature is correspondingly raised, thereby increasing the turbine inlet temperature with a given quantity of fuel or permitting a reduction in fuel quantity for the same turbine inlet temperature.
Heat from the turbine exhaust may be returnéd in part to the compressor inlet by the return duct 182. The turbine drives an energy utilizer represented by a generator 1.84.
As shown in Figures 8 and 9 the return flow may be controlled by one or more rows of guide vanes. This arrange-ment is similar to that above described in Figure 1 with a row , !. ` :

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of vane~ 250 at the inner end of the return duct 252, Figure 9, and another row o vanes 254 a~ the outer end of the return duct. The~e vanes may also serve to support the inner body 256 that defines the inner wall of the return duct. Each vane 254 is mounted to turn on a pin 258, Figure 10 that extends inwardly from the outer case 260 and is ~ecured a~ by threads 262 in the inner body. The outer end of tha pin has a flange 264 overlying the outer end of the pivot tube 266 carrying the vane. The end of the tube 266 has a ring 268 between the flange 264 and a boss 270 in the outer case. The ring permlts turning of the vane and locking it in the desired posit:ion.
The vanes 250 may be similarly mounted.
Other vanes 272 and 274 may be located at outer and inner ends of the cold return duct and being similarly mounted may be adjustable to control the cold return flow. The vane structure may-also serve to support the inner body at this end of the device.
It will be understood that each set of vanes may be individually adjusted thereby controlling the relative flows in the hot and cold returns and will permit adjustment of the flow to produce maximum performance of the unit.
In this arrangement, the initial fluid to establish the vortex is supplied ta~gentially of the return duct ~rough a nozæle 276 having a small angle from a normal to the axis to impart to the entering fluid a small longitudinal orientation ~;~
so that the vortex will move toward and en~er the radial entry , .
passage to the vortex tube.

As shown in these figures, a portion of the operating fluid may be withdrawn from either end of the device as by ~onduits 278 and 280 from the cold and hot ends respectively.

This portion of the operating fluid passes through a compressor 282 driven by power means 282a and is then reintroduced into ., g the system through tangential nozzles 276 and 286 of the type above described. Nozzle 276 is located in the cold return stream adjacent to the inlet passage 288, Figure 9, and noæzle 286 is located adjacent the outer end of the hot return stream.
Both nozzles are skewed to impart an axial flow to the vortex produced as indicated. Suitable valves 290 and 292 in the conduits 294 and 296 from the compressor to the nozzles parmit a further control of the system. Other valving as described above controls the amount of fluid removed from the system into the conduits 278 and 2800 The nozzles 276 and/or 286 may be adjustable to control the amount of axial component to the fluid discharged from them. Thu~ as shown in Figure 8 the nozzle is mounted to pivot on a radial pivot pin 293 with suitable stops not shown by which the angle may be adjusted~
The apparatus above described is based upon the Ranque-Hilsch tube concept of dividing a vortex flow into cold and hot discharges. It is equally adapted to other forms of energy separators. As shown in Figures 11 to 13, the device includes aligned rotors 3QO and 302 journalled in bearings 304 and 306 in the housing 308 and each carrying, on their inner ends, disks 310 and 312 each having a row of nozzles 314 and 316 therein. These nozzles, as shown in Figures 12 and 13 are supersonic convergent divergent nozzles and discharge tangentially to impart a rotary motion to discharging fluid and a reverse rotary thrust to the rotors. The nozzles may be of the type shown in Sohre 3,804,335. The nozzle discharge into an outer flow separation chamber 318 and the flow in this chamber is ~ivided by the operation of the device into a cold flow, moving the left, in passage 318a and a hot flow moving to the right, in passage 318b. Surrounding the nozzles is an axially movable guide 319 in the chamber that controls the dis-tribution of the hot and cold fluids and thus controls the ~ J

maximum temperatures in the cold and hot passages.
The return flow of the hot and cold fluids is in the return passages 320 and 322 defined around the rotor shafts by inner bodies 324 and 326, these bodies also defining along their outer surfaces the hot and cold passages 318a and 318b.
The inlets to the nozzles 314 and 316 ar~ at the inner ends of the return passages. The return flow is guided by end closures 328 and 330 axially slidable within the outer casing 308 and spaced from the end caps 332 and 334 that support the bearings for the rotors. ~hese cl~sure~ allow clearance around the rotor shaft~ to permit the introduction of operating fluid under pressure supplied by a compressor 336 driven by power means 336a. Operating fluid for supplying the compre~sor may be withdrawn from the outer ends of the hot and cold ducts a~
shown. Suitable valving 338 and 339 in the conduit~ 340 and 341 to and from the compressor per~it a control of the opera-tion of the device either alone or in conjunction with the movable end closures and the movable guide 319. Other valves 342 and 343 in conduits 344 and 345 control the quantity of fluid from the cold and hot ducts to be returned to the com-pressor.
The cold rotor 310 i9 driven by the thrust from the nozzles and the expansion of the fluid through the nozzles reduces the temperature of the 1uid entering the duct 318a.
This rotor nay drive a generator 346. ~ne hot rotor 312 is driven in a direction opposite to the thrust imparted by the nozzles 316 and thus heat the fluid discharying from these nozzles such that hot fluid is discharged into passage 318b.
A motor 348 drives the rotor 312 and may receive its power from the generator 346 through interconnecting leads 349 and a control switch 350. Alternatively leads 351 may supply electrical power from an external source.

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~7~5~31 In addition to the production of electrical energy the device may be used for heating and/or coolingO The ca~ing 308 has two heat exchangers 352 and 353 mounted thereon or fitted therein. The heat exchanger 353 surrounds the cold fluid duct and serves to supply an ~uxiliary cooling fluid for use in any coolin~ function such a~ air conditioning or refrigeration. rhe effect of ~his heat exchanger iB to heat the fluid in the cold duct so that it is nearly restored to the original nozzle inlet temperature. The heat exchanger 353 surrounds the hot fluid duct and serves to heat an auxiliary heating fluid for use where heat may be needed as in space heaters or other heating purposes. This exchanger removès enough heat from the hot fluid so that the fluid in the hot return passage i9 nearly at the original nozzle inlet tem-perature.
The device may be built not only in small sizes but its use in large scale units is feasible because of th~ sim-plicity of the processO Furthenmoxe, temperature differences of several thousand degrees are possible within the limits of the material of ~he device depending upon the fluids used and the operating pres~ures. Such devices could be utiliæed in tandem for producing extremely hot or cold temperatures.
Although many different fluids may be utilized, two or three phase fluids have interest~ For example wet steam could be used with the device serving as a condenser tcold side) and reheated (hot side3 with snow being discharged at the one end as a snow maker. Other uses of multi-phase fluids will be apparent.
Devices of this type can be utilized to avoid ther-mal pollution of rivers and other bodies of water by powerplants either conventional or nuclear, since the cooling of the power plant operating fluid or fluids can be readily '~r~

accomplished without the need for using water from rivers or lakes. The heat reclained by the device could then produce additional power.
Although the invention ha~ been shown and described with respect to preferred embodiments thereof, it should be understood by those skilled in the art that the various changes and omissions in the form and detail thereof may be made therein without departing from the spirit and the ~cope of the invention.

Claims (8)

The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:-

1. A vortex tube system including:
a casing having a fluid separation chamber in which a fluid introduced in a vortex is separated into hot and cold swirling streams;
means for introducing the fluid into the chamber to produce a helical flow therein for causing the fluid separation;
hot and cold conduits connected to said chamber to receive the hot and cold swirling streams of fluid, one of said conduits including a return duct for the return of the fluid therein to the chamber downstream of said means, said return duct being connected to minimize kinetic energy loss from the swirling fluid; and energy exchange means associated with said conduits for the removal of energy from the hot stream and addition of energy to the cold stream.

2. A system as in claim 1 in which both conduits include return ducts for a return of the fluids therein to the chamber to join the helical flow therein, said ducts being arranged to maintain a significant kinetic energy swirl in the fluids as they reenter the helical flow.

3. A system as in claim 2 in which one of the energy ex-change means includes a turbine for the removal of energy from the stream.

4. A system as in claim 2 including means for bleeding a part of one of the fluid streams therefrom.

5. A system as in claim 2 in which at least one of the energy exchange means includes a heat exchanger by which to change the energy level of a secondary fluid in the exchanger by exchange of energy between the secondary fluid and the operating fluid in the system.

6. A system as in claim 1 in which the flow in the con-duits is helical and variable position vanes in at least one conduit provides control of the helical flow.

7. A system as in claim 2 in which energy exchange means associated with the conduits remove heat energy from the hot stream and add heat energy to the cold stream so that the return-ing streams entering the chamber are nearly at the same tempera-ture.

8. A system as in claim 2 including a compressor for pressurizing the fluid and a supersonic nozzle through which the pressurized fluid is introduced into the chamber.