US2720091A

US2720091A - Air cycle cooling device employing vortex tube

Info

Publication number: US2720091A
Application number: US420875A
Authority: US
Inventors: Helmut R Schelp
Original assignee: Garrett Corp
Current assignee: Garrett Corp
Priority date: 1949-10-14
Filing date: 1954-04-05
Publication date: 1955-10-11
Anticipated expiration: 1972-10-11

Description

United States Patent AIR CYCLE COOLING DEVICE EMPLOYIN G VORTEX TUBE Helmut R. Schelp, Pacific Palisades, Calif., assignor to The Garrett Corporation, Los Angeles, Calif, a corporation of California Original application October 14, 1949, Serial No. 121,436. and this application April 5, 1954, Serial No.

12 Claims. (Cl. 62-138) This is a divisional application based on Figs. 3, 3a and 4 of my copending application, Serial No. 121,436, filed October 14, 1949, for Air Conditioner Employing an Expansion Evaporation Air Cycle.

The invention described herein may be manufactured and used by or for the United States Government for governmental purposes without the payment to me of any royalty thereon.

It is an object of the invention to provide a simple device for cooling air wherein air is passed through a vortex tube and wherein means are provided for sprayinga liquid into the air upstream from the cooled air outlet of the vortex tube.

A further object of the invention is to provide a cooling device of the character set forth in the preceding paragraph having a spray chamber in communication with the interior of .the vortex tube, and a further object of the invention is to provide a device of this character wherein the spray chamber has an outlet for a portion of the air originally fed into the vortex tube.

A further object of the invention is to provide an air cooling device having a vortex tube with a heat exchanger connected to its cooled air outlet, having means for spraying, a vaporizable liquid into the air stream upstream from the cooled air outlet of the vortex tube and also having means for applying suction to the outlet of the heat exchanger to elfect an expansion of the air as it passes through the heat exchanger, there being means for passing an independent flow of air to be cooled through the heat exchanger in heat exchange relation to the air which is passed through the vortex tube.

A further object of the invention is to provide a device for cooling at gas having a vortex tube with an inlet and a cooled gas outlet at one end and a warm gas outlet at the opposite end, there being means for spraying a vaporizable liquid into the gas upstream from the cooled gas outlet of the vortex tube and there being also heat exchangers connected to the outlets of the vortex tube and also means for applying suction to the outlets of these heat exchangers so that there will be a rarification of the gas which passes through the heat exchangers.

Further objects and advantages of the invention may be brought out in the following part of the specification wherein the detailed description of the parts of the invention is for the purpose of disclosure, without the intention of limiting the scope of the invention set forth in the appended claims.

Referring to the drawings which are for illustrative purposes only:

Fig. 1 is a schematic sectional view of a form of my invention employing a vortex tube having a closed rear end;

Fig. 2 is a fragmentary sectional view taken as indicated by the line 22 of Fig. l

Fig. 3 is a schematic sectional view showing a form of my invention employing a vortex tube having an open rear end.

In the embodiment of the invention shown in Fig. 1,

2,720,091 Patented Oct. 11, 1955 'ice I schematically indicate a vortex tube 26 having an axially extending cooled air outlet opening formed in the front end wall 27a of the vortex tube device 26. From a source of supply working air to be cooled is fed from a room or chamber 32 through a duct 31 and a tangentially arranged inlet nozzle 26a into the vortex tube 26 adjacent the front end wall 27a thereof. Herein, the term air is used in its broad sense as meaning a combination of gases or a single gas.

In the vortex or Ranque tube as known to the art, in addition to the relatively small cooled air outlet opening 27 at the front end of the tube, there is a larger opening at the rear end through which the relatively warm or hot stream of air passes. In my present invention, however, this larger opening, indicated at 28 extends into an enlarged spray chamber 29. From the inspection of the drawing, it will be perceived that the wall 28a of the vortex tube extends rearwardly from the front end wall 27a and that the chamber 29 is formed. by closing the rear end of the tube wall 28a by means of a rounded wall 29a which is a continuation of the wall 28a.

The cold air outlet 27 of the vortex tube 26 extends through a heat exchanger 33 and the air passing through the exchanger flows to some kind of suction device, such as a suction blower or jet pump, not shown. A stream of conditioning air flows along a main duct 34 under the driving action of a fan 35 driven by a motor 36 or any source of power. The air from the atmosphere is passed over the exchanger tubes 33a where it is cooled by the working air and dehumidified before flowing intothe room 32. While it is preferred to use the room or return air, or exhaust air, as a source of the working air which is passed through the vortex tube 26, it is also possible to use atmospheric air instead.

In the system shown in Fig. 1, the special application of the Ranque tube is the important feature. The cold working air flows out through the cooled air outlet 27, but the warmer air which normally flows out through the larger rear end opening of the Ranque tube as known to the art, is instead met with water spray 30a which issues from a spray nozzle 30 disposed in the chamber portion 29 of the vortex tube 26. The wet bulb temperature in the chamber 29 will depend on the relative humidity of the air entering the vortex tube along the conduit 31, thus it is seen that the exhaust air from the room 32 would usually be preferable to outside air for better efliciency. The warmer air, now reduced to wet bulb temperature mixes with the colder air leaving the vortex tube by way of the cooled air outlet 27, to the heat exchanger 33. As the air becomes heated in passing through the tubes 33a it will evaporate more moisture, thus helping to prevent a temperature rise of the air during the tube traverse. Also, in the form of the invention shown in Fig. 1, a form of expansion nozzle is provided with. the result that the air entering the vortex tube is cooled by expansion, and in conjunction with the spray chamber 29 and spray nozzle 30 provides a compact and eflicient arrangement for cooling the air. Water is supplied to the spray nozzle 30 through a valve P arranged to be regulated by manipulation of a handle such as shown at 8a. In the form of the invention shown, the wall forming the spray chamber 29 is a part of or continuation of the vortex tube wall 28a, and therefore the spray 30a actually sprays water into the interior of the vortex tube, and therefore there is additive water in the working air at the timeit is in the vortex tube and prior to the time the working air leaves the vortex tube. 1

In the form of the invention shown in Fig. 3, I provide a source of working air shown as a room 32, from which air is delivered through a duct 31 to the inlet nozzle 26a of a vortex tube 26 having a cooled air outlet 27 in its front end wall 27a. Cooled air from the outlet 27 is conducted through a heat exchanger 33 disposed in an air duct 34. The larger opening 28 of the vortex tube 26 merges into a conduit 49 wherein is located a spray head 50, which receives water under pressure from a variable pump P havinga regulating lever 8a, adapted to spray water in a fine mist both forwardly and rearwardly. The conduit 49 extends to a second or auxiliary heat exchanger 57 mounted in the duct 34. The air which has passed through the tubes 33a of the heat exchanger 33 enters a short conduit 58 through which extends a suction means in the form of a jet pipe 59 adapted to carry high pressure air, engine exhaust gas or steam to provide a jet pump and thus maintain fiow through the vortex tube 26. The conduit 58 merges in a second suction means in the form of a jet pipe 61 extending into a conduit 60 from the secondary heat exchanger 57. The combined flows from the conduit 58 and the pipe 59 merge and are blown from the second jet pipe 61 to provide a suction on the conduit 49 to finally exhaust through an outlet pipe 62.

'flow along the inner surface of the wall of the tube 26 into the conduit 49 where the warm air meets the water spray from the nozzle 50. This air is now reduced to wet bulb temperature by evaporation of moisture as it passes :toward the secondary heat exchanger 57. The cooled air carries along an excess of free moisture, so that the air during passage through the tubes of the heat exchanger 57 tends to remain cool because increase in temperature enables it to evaporate still more moisture. There is also free moisturein the air which due to suction of the device 59 passes in rarefied state from the cold air outlet 27 of the vortex tube 26 and through the tubes 33a of the heat exchanger 33, so that as this air passes through the tubes 33a it will expand and free moisture will be evaporated and the air will be maintained at a lower temperature than if the water spray were not present. The speed of the fan 35 should be regulated to provide the proper change of air in the room per unit of time, depending upon the type of room being air conditioned.

Although the improved forms of vortex tubes have been shown in conjunction with systems wherein working air is cooled and then employed, by use of heat exchange means, to cool air which is being fed into a space which is to be cooled, the usefulness of the vortex tubes is not limited to the system shown, but the cooled air leaving the cooled air outlet 27 may be employed for any purpose for which it is suited. r

I claim:

1. In an air cycle air conditioning system, a vortex tube including an air inlet for working air and a pair of oppositely extending air outlets each of a different diameter, a spray chamber directly connected to said air outlet of larger diameter and having mounted therein nozzle means for introducing a fine spray of water into the working air for evaporative cooling thereof, a heat exchanger directly connected to said air outlet of smaller diameter and providing a path for said working air after leaving said expansion device, a suction device including an air inlet for the working air leaving said heat exchanger and including an air discharge outlet open to the atmosphere, means to regulate the flow of water through said nozzle means whereby the moisture content of the working air issuing from said air discharge outlet is capable of regulation to obtain total saturation, and duct means to conduct conditioning air through said heat exchanger along arpath separate from the working air path but in heat exchange relation with respect thereto.

2. An air cycle air conditioning system as defined in claim 1 wherein said spray chamber is closed except for its communication with said air outlet of larger diameter of said tube.

3. In an air cycle air conditioning system, a vortex tube including an air inlet for working air and a pair of oppositely extending air outlets each of a different diameter, means forming a first path for flow of a portion of the working air comprising a conduit extending from said air outlet of larger diameter and having mounted therein nozzle means for introducing a fine spray of Water into the working air for evaporative cooling thereof, a first heat exchanger connected to said conduit and having an outlet connected to the inlet side of a first suction device, means forming a second path for flow of a portion of the working air comprising a second heat exchanger directly connected to said air outlet of smaller diameter, the outlet of said second heat exchanger being connected to the inlet side of a second suction device, means to regulate the flow of water through said nozzle means whereby the moisture content of the working air issuing from said suction devices is capable of regulation to obtain total saturation, and duct means to conduct conditioning air through said heat exchangers along a path separate from the working air paths but in heat exchange relation with respect thereto.

4. In an air cycle air conditioning system as recited in claim 3, said first and second suction devices being in the form of jet pumps operating in series and discharging to the free atmosphere.

5. In an air cycle air conditioning system: a vortex tube; means for delivering air to the inlet of said vortex tube; piping for conducting cooled air away from the cooled air outlet of said vortex tube; and means for delivering a spray of liquid into said air in said tube at a point spaced axially from said inlet and said cooled air outlet of said vortex tube.

6. In an air cycle air conditioning system: a vortex tube; means for delivering air to the inlet of said vortex tube; piping for conducting cooled air away from the cooled air outlet of said vortex tube; means for delivering a spray of liquid into said air upstream from said cooled air outlet of said vortex tube; and means for applying suction to the air which leaves said cooled air outlet of said vortex tube.

7. In an air cycle air conditioning system: a vortex tube; means for delivering air to the inlet of said vortex tube; piping for conducting cooled air away from the cooled air outlet of said vortex tube; means for delivering a spray of liquid into said air upstream from said cooled air outlet of said vortex tube; a heat exchanger connected to said cooled air outlet of said vortex tube; and means for applying suction to the air as it passes through said heat exchanger.

8. In an air cycle air conditioning system: a vortex tube having an inlet and a cooled air outlet at one end and a chamber at the other end;'means for delivering air to the inlet of said vortex tube; piping for conducting cooled air away from the cooled air outlet of said vortex tube; and means for delivering an evaporative liquid to the interior of said chamber.

9. In an air cycle air conditioning system: a vortex tube; means for delivering air to the inlet of said vortex tube having an air inlet and a cooled air outlet at one end thereof and a warm air outlet at the other end thereof; piping for conducting cooled air away from the cooled air outlet of said vortex tube; means for delivering a. spray of liquid into said air upstream from said cooled air outlet of said vortex tube; and means applying suction to said outlets of said vortex tube.

10. In an air cycle air conditioning system: a vortex tube; means for delivering air to the inlet of said vortex tube having an air inlet and a cooled air outlet at one end thereof and a warm air outlet at the other end thereof; piping for conducting cooled air away from the cooled air outlet of said vortex tube; means for delivering a spray of liquid into said air upstream from said cooled air outlet of said vortex tube; first and second heat exchangers connected respectively to said outlets of said vortex tube so that air from said vortex tube will pass therethrough; and means for passing a flow of air to be cooled through said heat exchangers in heat exchange relation to said first named air which passes through said heat exchangers.

11. In an air cycle air conditioning system: a vortex tube; means for delivering air to the inlet of said vortex tube having an air inlet and a cooled air outlet at one end thereof and a Warm air outlet at the other end thereof; piping for conducting cooled air away from the cooled air outlet of said vortex tube; means for delivering a spray of liquid into said air upstream from said cooled air outlet of said vortex tube; first and second heat exchangers connected respectively to said outlets of said vortex tube so that air from said vortex tube will pass therethrough; means for passing a flow of air to be cooled through said heat exchangers in heat exchange relation to said first named air which passes through said heat exchangers; and

1 from said cooled air outlet; a spray for delivering a vaporizable liquid into the air which leaves said Warm air outlet of the vortex tube; and means to be cooled comprising Walls defining a space connected to said Warm air outlet so as to receive the fluids which are discharged therefrom.

References Cited in the file of this patent UNITED STATES PATENTS 1,952,281 Rangue Mar. 27, 1934 FOREIGN PATENTS 482,104 Canada Apr. 11, 1952 926,452 France Oct. 2, 1947