US3730263A - Heat pump - Google Patents

Abstract

A heat pump having a closed cycle refrigeration system including a condenser, evaporator and compressor and a vaporized fluid power system for driving the compressor including a boiler and condenser. The condensers are arranged in such a manner that heat is transferred to the ambient when the apparatus is utilized to cool a conditioned zone and heat is transferred to the conditioned zone when the apparatus is utilized to heat a conditioned zone. The evaporator simultaneously removes heat from the conditioned zone during cooling thereof and removes heat from the ambient during heating of the conditioned zone. A fluid bypass system is provided to supply heat directly from the boiler to the condenser of the vaporized fluid power system during extreme, low ambient temperature conditions when the conditioned zone is being heated.

Description

United States Patent Anderson 1 HEAT PUMP I James H. Anderson, I615 Hilock Lane, York, Pa.

[22] Filed: Nov. 26, 1969 [21] App]. No.: 877,553

[76] Inventor:

Related US. Application Data [62] Division of Ser. No. 703,l56, Feb. 5, I968, Pat. No.

1 1 May 1, 1973 Primary Examiner-Charles Sultalo Attorney-Kemon, Palmer and Estabrook 5 7 ABSTRACT A heat pump having a closed cycle refrigeration system including a condenser, evaporator and compressor and a vaporized fluid power system for driving the compressor including a boiler and condenser. The condensers are arranged in such a manner that heat is transferred to the ambient when the apparatus is utilized to cool a conditioned zone and heat is transferred to the conditioned zone when the apparatus is utilized to heat a conditioned zone. The evaporator simultaneously removes heat from the conditioned zone during cooling thereof and removes heat from the ambient during heating of the conditioned zone. A fluid bypass system is provided to supply heat directly from the boiler to the condenser of the vaporized fluid power system during extreme, low ambient temperature conditions when the conditioned zone is being heated.

5 Claims, 5 Drawing Figures Patented May 1, 1973 v 3,730,263

2 Sheets-Sheet 1 FIG.

INVENIOR JAMES H. ANDERSON l J v (I 1 V v 124 BY/jm ATTORNHJ Patented May .1, 1973 3,730,263

2 Sheets-Sheet 2 1 umui INVENTOR' JAMES H. ANDERSON HEAT PUMP CROSS-REFERENCE TO RELATED APPLICATION This is a division of application Ser. No. 703,156 filed Feb. 5, I968, now U.S. Pat. No. 3,519,066.

BACKGROUND OF THE INVENTION I-Ieat pump apparatus are in wide use for heating and cooling buildings in the art. Prior art heat pumps generally include a refrigeration system having a contional or supplementary heating apparatus in conjunction therewith.

SUMMARY OF THE INVENTION This invention relates generally to devices for transferring heat energy from a low temperature locality to a high temperature locality and more specifically to a heat pump for accomplishing such transfer by mechanical means involving the compression and expansion of a fluid by mechanical refrigeration. The invention relates more particularly to such an apparatus as applied to heating or cooling a building by transferring heat from or to the ambient air.

This invention provides a novel heat pump apparatus which avoids the disadvantages of the prior art by furnishinga vaporized fluid power system including a condenser for powering a closed cycle refrigeration system whereby the condensers of the vaporized fluid power system and of the refrigeration system are utilized to selectively transfer heat to the ambient or to the conditioned zone while the evaporator of the refrigeration system is utilized to extract heat from the-ambient or the conditioned zone. i

The invention also provides a novel evaporator-condenser structure which may be quickly manipulated to switch from the function of extraction of heat from, to the transfer of heat to the conditioned zone.

The invention further provides novel means for bypassing the power unit of the vaporized fluid power system for circulating heat energy directly to the condenser thereof to increase the heat output of the apparatus during heating of the condition zone at low ambient temperatures.

In the preferred embodiment, the invention comprises a refrigeration system comprising a condenser, expansion means, evaporator and compressor, the compressor being driven bya vaporized fluid power system comprising a rotary boiler, turbine and condenser. The condensers and evaporator are rotatably mounted in opposed relationship so that the evaporator may be mechanically moved from communication with the conditioned zone to communication with the ambient while the condensers are simultaneously moved F2 means to switch from transferof heat from, to transfer of heat to the conditioned zone. A bypass is provided to communicate fluid frornthe boiler of the vaporized fluid power system, around the turbine, directlyto the condenser thereof to increase the heat output of the vaporized fluid power system when required for heating the conditioned zone. I

These and other objects of the invention will become better understood to those skilled in the art by reference to the following detailed description when viewed in light of the accompanying drawings wherein like numerals throughout the figures thereof indicate like components and wherein:

FIG. 1 is a schematic view of a heat pump apparatus in accordance with the invention;

FIG. 2 is a fragmentary plan view, in section, of the evaporator-condenser structure of the invention of FIG. 1 disposed in ducting and configured to transfer 20 heat from the conditioned zone;

FIG. 3 is a view similar to FIG. 2 showing the evaporator with the condenser structure of the invention disposed in such a manner to transfer heat to the conditioned zone;

5 FIG. 4 is a schematic view similar to FIG. 1 showing another embodiment of the invention; and

FIG. 5 is afragmentary plan view similar to FIG. 3 showing the evaporator-condenser structure of the embodiment of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1 of the drawings, the heat pump comprises a refrigeration apparatus including a condenser l0.communicating in series through a conduit 12 with an expansion valve 14, evaporator 16 and i a compressor 18. Power for the compressor 18 is derived from a vaporized fluid power system comprising a turbine .20, connected to the compressor 18 at the portion thereof supplying fluid to the turbine 20,

and serves to increase the pressure of the fluid circulating from the condenser.26 to the boiler 30 in a manner well known in the art.

A bypass conduit 34, including a valve 36, communicates with the conduit 24 on either side ofthe turbine 20 to provide a means to selectively bypass theturbine. Air circulating means such as fans 38 and 40 are disposed to induce airflow over the evaporator 16 and the condensers l0 and-26 respectively.

matically as an axial flow rotary turbine-compressor, for example, the compressor may take the form of a radial flow turbineand/or compressor or reciprocatory motor-compressor structure if so desired.

In the disclosed embodiment, it is contemplated that fluid in the refrigeration system will comprise one of V the suitable conventional refrigerants such, for example,-as ammonia or one of the fluorocarbons, while the fluid in the vaporized fluid power system will preferably comprise a halogenated hydrocarbon suitable for the purpose such, I for example, as Freon ll4 (dichlorotetrafluoroethane CClFgCClFz) or Freon-318 (octafluorocyclobutane C4F A vaporized fluid power system particularly suitable for this purpose is disclosed in U.S. Pat. No. 3,315,466, issued Apr. 25, 1967. In the 1 event that such a fluid power system with a rotary turbine-compressor structure is utilized to transmit power between the vaporized fluid power system and the refrigeration system, segregation of the fluids and lubrication of the turbine-compressor may be accomplished with the bearing and seal system disclosed in U.S. Pat. No. 3,258,199, issued June 28, 1966.

In utilizing fluids such as the above-mentioned Freons as working fluids in the vaporized fluid power system, cavitation problems are encountered in transmitting the fluid from the condenser to the boiler. It is contemplated that such problems, if encountered, can be overcome by subcooling the fluid supplied to the injector 28 by means of a structure such as the subcooling column 16 disclosed in the'afore-mentioned U.S. Pat. No. 3,315,466.

Although the boiler 30 may be of any of the types common in the art, for the purposes of compactness and eff ciency as well as for particular adaptability for use with fluorocarbons, it is preferred that a boiler structure such as the rotary vapor generator disclosed in U.S. Pat. No. 3,260,050, issued July 12, 1966, be utilized. If such a boiler is used, as disclosed in that patent, a major portion of the pumping work necessary for circulating fluid through the vaporized fluid power system can be accomplished in the rotary boiler and the work required from the injector can thereby be reduced or eliminated. For this reason, it is possible that the injector 28 may be, in some cases, eliminated from the system by proper design.

Referring now to FIG.' 2 of the drawings, the evaporator 16 and the condensers l and 26 are shown mounted in opposed substantially coplanar relationship to one another on a rotatable member 42, disposed between a conditioned zone duct 44 and an ambient duct 46. The fans 38 and 40 are mounted in the ducts 44 and 46 respectively to circulate air as shown by the arrows through the ducts. A movable panel 48 is disposed in an opening 50,.formed between the ducts 44 and 46 and is mounted for rotation on the rotatable member 42 in perpendicular relationship to the condensers and 26 and the evaporator 16. A suitable elastic seal 52 is provided between the panel 48 and the opening 50 to block communication between the ducts 44 and 46 when the panel 48 is aligned therewith as illustrated.

A wall 56 segregates a conditioned zone, indicated generally at 58, from an ambient area, indicated generally at 60. The duct 44 penetrates the wall 56 through openings 62 and 64 to provide communication with the conditioned zone 58.

In operation, with the apparatus in the configuration illustrated in FIGS. 1 and 2 and the valve 36 (FIG. 1) closed, the conditioned zone 58 is cooled by energization of the boiler 30 and the fans 38 and 40. Upon energization of the boiler, as more particularly described in aforementioned U.S. Pat. No. 3,260,050, the vaporized fluid power system operates generally in accordance with that disclosed in aforementioned U.S. Pat. No. 3,315,466 with the substitution of the injector 28 for the main pump 20 and elimination of the recuperator 10 thereof. Heated, high pressure fluid is delivered through the conduit 24 to the turbine 20, thereby driving the compressor 18 through the shaft 22. Turbine exhaust fluid is directed through the conduit ,24 --to the condenser 26 whereby heat is removed therefrom by passage of air therethrough by means of the fan 40 and the duct 46. Fluid is returned to the boiler 30 through the conduit 24 by means of the influence of the injector 28 deriving energy for increasing the feed pressure to the boiler from a portion of high energy fluid diverted thereto through the branch conduit 32 as described above.

Fluid, compressed in the compressor 18, is circulated through the condenser 10 for removal of heat therefrom by air flow directed thereover by means of the fan 40 and the duct 46. The cooled high pressure fluid is then transmitted through the conduit 12 to the expansion valve 14 for expansion and cooling thereof in a conventional manner. The expanded, cooled fluid is then transmitted through the evaporator 16 for transfer of heat thereto from conditioned zone air directed thereover by means of the fan 38 and the duct 44 in a manner well known in the refrigeration art. The expanded, warmed refrigeration fluid is then returned to the compressor 18 for recycling thereof in a closed cycle.

It should be noted at this point that the arrangement of the condensers l0 and 26 relative to the direction of air flow through the duct 46 is particularly efficient since the Coefficient of Performance of a Carnot cycle is a function of the difference between the temperature of heat in and the temperature of heat rejected divided by the temperature of heat in as in the following relationship:

COP Carnot T1 2/ 1 while the Coefficient of Performance of a refrigerator is a function of the temperature of heat in, divided by the difference between the temperature of heat rejected and the temperature of heat in as in the following relationship: a

Reh-la.' a/ T2 T3 The overall Coefficient of Performance is then as follows: I

Total 1 z/ i X s/ z a When the heat rejector or condenser structures are placed in series, either the hot body of heat or the cold body of heat can be rejected at the higher temperature. Presuming the following:

T, temperature of heat supplied I T temperature of heat rejected from the power condenser 26 T temperature of heat rejected from the refrigerator condenser 10 T temperature of heat supplied to refrigerator the overall Coefficient of Performance of the heat pump then is as follows:

For example, by first placing the refrigerator condenser 10 upstream to receive the coolest supply of air flow and assuming the following values (absolute):

For these parameters, the Coefficient of Performance is calculated as follows: i t

COP=425/l010 505/80T2.59

By reversing the condensers and placingthe power condenser 26 upstream of the refrigeration condenser with the above same assumptions, the parameters are:

The Coefficient of Performance then is as follows:

COP 425/1010 505/90 2.36 or an increase in Coefficient of Performance of 0.23 by proper arrangement of the condensers, as illustrated.

Referring now to FIG. 3 of the drawings, the evaporator-condenser of FIG. 2 is shown rotated, 180 to place the condensers l0 and 26 in the conditioned zone duct 44 and the evaporator 16 in the ambient duct 46. The panel 48 once more aligns with the ducts 44 and 46 to provide segregation of airflow therebetween.

Since fluid connection from the condensers 10 and 26 and the evaporator 16 with the remainder of the system must be accomplished through six conduits as described above, it is preferable, in order to avoid multiple seal problems, to design the connections in such a manner that communication is provided while allowing 180 rotation of the structure. Such communication may be accomplished by providing tubes formed as helical springs twistable through 180 or communicating tubes of sufficient length to permit a 180 twist without yielding the tube material. Ithas been found that such can be accomplished with steel tubes of the following characteristics, for example:

E,= 12 X 10 psi Straight length 58.9

S 20,000 psi d=0.625 inches It should be noted at this point, that since the condenser side of the structure would normally: have a higher resistance to airflow than the evaporator side, it is advisable to make provision for increasing the airflow through the condenser side of the structure. This could be accomplished by providing a two-speed arrangement on the fans 38 and 40 so that the fans may be switched from a higher airflow when the condenser section is disposed in a particular duct to a lower airflow when the evaporator side is disposed therein. Another alternative would be to mount a supplementary fan on the condenser structure to automatically compensate for the additional flow resistance therethrough.

With the apparatus structured in accordance with the configuration shown in FIG. 3, heat is supplied to the conditioned zone by means of rejection from the condensers l0 and 26 disposed in the duct 44 while heat is extracted from air circulated through the duct 46 by the evaporator 16. Heat supplied in this manner is suitable for moderate cold weather conditions and temperature may be controlled at a desired level by regulating the amount of heat supplied to either or both of the condensers 10 or 26. In moderate weather conditions, the compressor supplies some heat to the condenser 10 while whatever additional heat is required may be extracted from the condenser 26.

In very cold weather conditions, the compressor 18 will normally not'supply sufficient heat through the condenser 10 to enable the heat derived from the turbine through the condenser 26 to suitably'augment the heat output. Under these conditions, it is more efficient to remove the compressor from the line and direct heat generated by the boiler 30. directly to the condenser 26. This is accomplished by opening the valve 36 and bypassing the turbine20 to channel the heated fluid for v the boiler 30 directly through the conduit 34 to the condenser 26, thereby channeling all of the heat from the boiler 30 to the airflow directly.

Referring now to FIG. 4 of the drawings, another embodiment in accordance with the invention is illustrated. Since fluorocarbons such as the above-mentioned Freons are equally suitable for use as refrigants, the heat pump can utilize a single fluid system. This is accomplished by joining the exhaust from the turbine and the discharge from the compressor and directing the flow to a common condenser. In such a system, illustrated in FIG. 4, components thereof corresponding to like of the preceding figures are indicated by like numerals of the next higher order. In this figure the exhaust from the turbine 120 is manifolded into a combined condenser 166 through the conduit 124 with the exhaust or discharge from the compressor 118 fed through the conduit 1l2. To condensate from the com denser 166 is divided subsequent to condensation in the conduit 124, for return to the boiler 130, andthe conduit 112, for channeling through the expansion valve 114. The operation of the remainder of the system is identical to that described for the embodiment of FIG. 1.

In FIG. 5, the evaporator-condenser structure is shown disposed in the ambient duct 146 and conditioned zone duct 144 and operates in a manneridentical to that described for the embodiment of FIGS. 2 and 3 for switching from cooling, as illustrated, toheating of the conditioned zone.

In the single fluid system disclosed in FIGS. 4 and 5, it is possible to substitute an injection or jet type compression apparatus for the rotary turbine-compressor illustrated. The principles of operation of such an apparatus are well known in the steam power plant art I and are illustrated by the injector 28 utilized in the embodiment of FIG. 1. In such a device, the high energy, high temperature fluid from the boiler 130 would be injected through the conduit 124 into the low energy fluid in the conduit 112 after passage thereof through the evaporator 116, thereby raising the pressure and energy level of the fluid entering the condenser'166. After cooling in the condenser 1166, the high energy fluid would then be divided as described above, a portion thereof returning to the boiler 130 while the remainder thereof is expanded through the expansion valve 114 for reentry into the evaporator 116..

What has been set forth above is intended as exemplary of teachings in accordance with the inventionto enable those skilled in the art in the practice thereof. It should, therefore, be understood that, withinthe scope of the appended claims, the invention may be practiced other than as specifically described. What is new and therefore intended to be protected by Letters Patent of the United States is:

1. In a heat pump system having parallel abutting airflow ducts communicative with zones of differenttemperature, the improvement comprising a heat exchange assembly including a compressor with driving means therefore, and evaporator and at least one condenser, said condenser and evaporator of said heat assembly mounted on a rotatable member in an opening between said ducts with said compressor and driving means therefore arranged externally of said ducts, said condenser mounted on said rotatable member on one side of the axis of rotation of said member, said evaporator mounted in adjacent, substantially coplanar relationship to said condenser on the other side of said axis of rotation of said member, and a panel mounted substantially normal to said condenser and evaporator and intercepting said axis of rotation, said opening being substantially equal in area to the combined area of said condenser and evaporator, said panel being coextensive and alignable in said opening with the common walls of said ducts to provide flow division there between.

2. A heat pump system in accordance with claim I wherein said heat pump comprises a vaporized fluid power system including a power condenser, and a closed cycle refrigeration system including a refrigeration condenser.

3. A heat pump system in accordance with claim 2 wherein said power condenser is disposed in adjacent, coextensive relationship on the upstream side of said refrigeration condenser.

4. In a heat pump system as set forth in claim 2 wherein said refrigeration system includes a compressor driven by said power condenser.

5. In a heat pump system as set forth in claim 1 wherein said airflow ducts include multi-speed means for directing the flow of air through one of said ducts at a speed different than the flow of air through said other duct.

Claims (5)

1. In a heat pump system having parallel abutting airflow ducts communicative with zones of different temperature, the improvement comprising a heat exchange assembly including a compressor with driving means therefore, and evaporator and at least one condenser, said condenser and evaporator of said heat assembly mounted on a rotatable member in an opening between said ducts with said compressor and driving means therefore arranged externally of said ducts, said condenser mounted on said rotatable member on one side of the axis of rotation of said member, said evaporator mounted in adjacent, substantially coplanar relationship to said condenser on the other side of said axis of rotation of said member, and a panel mounted substantially normal to said condenser and evaporator and intercepting said axis of rotation, said opening being substantially equal in area to the combined area of said condenser and evaporator, said panel being coextensive and alignable in said opening with the common walls of said ducts to provide flow division there between.

2. A heat pump system in accordance with claim 1 wherein said heat pump comprises a vaporized fluid power system including a power condenser, and a closed cycle refrigeration system including a refrigeration condenser.

3. A heat pump system in accordance with claim 2 wherein said power condenser is disposed in adjacent, coextensive relationship on the upstream side of said refrigeration condenser.

4. In a heat pump system as set forth in claim 2 wherein said refrigeration system includes a compressor driven by said power condenser.

5. In a heat pump system as set forth in claim 1 wherein said airflow ducts include multi-speed means for directing the flow of air through one of said ducts at a speed different than the flow of air through said other duct.

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