GB2177497A - Air heating or cooling apparatus - Google Patents

Air heating or cooling apparatus Download PDF

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Publication number
GB2177497A
GB2177497A GB08610989A GB8610989A GB2177497A GB 2177497 A GB2177497 A GB 2177497A GB 08610989 A GB08610989 A GB 08610989A GB 8610989 A GB8610989 A GB 8610989A GB 2177497 A GB2177497 A GB 2177497A
Authority
GB
United Kingdom
Prior art keywords
air
air conditioning
conditioning apparatus
heat pump
accordance
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08610989A
Other versions
GB2177497B (en
GB8610989D0 (en
Inventor
Veit Merges
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Airbus Defence and Space GmbH
Original Assignee
Messerschmitt Bolkow Blohm AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DE19853516975 external-priority patent/DE3516975A1/en
Priority claimed from DE19853516961 external-priority patent/DE3516961A1/en
Application filed by Messerschmitt Bolkow Blohm AG filed Critical Messerschmitt Bolkow Blohm AG
Publication of GB8610989D0 publication Critical patent/GB8610989D0/en
Publication of GB2177497A publication Critical patent/GB2177497A/en
Application granted granted Critical
Publication of GB2177497B publication Critical patent/GB2177497B/en
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F12/00—Use of energy recovery systems in air conditioning, ventilation or screening
    • F24F12/001—Use of energy recovery systems in air conditioning, ventilation or screening with heat-exchange between supplied and exhausted air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F1/00—Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
    • F24F1/02—Self-contained room units for air-conditioning, i.e. with all apparatus for treatment installed in a common casing
    • F24F1/028—Self-contained room units for air-conditioning, i.e. with all apparatus for treatment installed in a common casing characterised by air supply means, e.g. fan casings, internal dampers or ducts
    • F24F1/0287—Self-contained room units for air-conditioning, i.e. with all apparatus for treatment installed in a common casing characterised by air supply means, e.g. fan casings, internal dampers or ducts with vertically arranged fan axis
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
    • F02G1/00—Hot gas positive-displacement engine plants
    • F02G1/04—Hot gas positive-displacement engine plants of closed-cycle type
    • F02G1/043—Hot gas positive-displacement engine plants of closed-cycle type the engine being operated by expansion and contraction of a mass of working gas which is heated and cooled in one of a plurality of constantly communicating expansible chambers, e.g. Stirling cycle type engines
    • F02G1/0435—Hot gas positive-displacement engine plants of closed-cycle type the engine being operated by expansion and contraction of a mass of working gas which is heated and cooled in one of a plurality of constantly communicating expansible chambers, e.g. Stirling cycle type engines the engine being of the free piston type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F1/00—Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
    • F24F1/02—Self-contained room units for air-conditioning, i.e. with all apparatus for treatment installed in a common casing
    • F24F1/03—Self-contained room units for air-conditioning, i.e. with all apparatus for treatment installed in a common casing characterised by mounting arrangements
    • F24F1/031—Self-contained room units for air-conditioning, i.e. with all apparatus for treatment installed in a common casing characterised by mounting arrangements penetrating a wall or window
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/14—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the cycle used, e.g. Stirling cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2309/00—Gas cycle refrigeration machines
    • F25B2309/001—Gas cycle refrigeration machines with a linear configuration or a linear motor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/56—Heat recovery units

Abstract

Air conditioning apparatus has a heat pump for the heating and cooling of enclosed rooms, the apparatus communicating both with the air in the room and with external air. The heat pump comprising a free-piston Stirling unit driven with an oscillating movement by a driving machine. The air conditioning apparatus having separate channels for stale air and fresh air and being equipped with means for altering the air supply or the direction of flow in order to enable the method of operation (cooling/heating) to be selected. <IMAGE>

Description

SPECIFICATION Air conditioning apparatus This invention relates to an air conditioning apparatus incorporating a heat pump for heating and cooling closed spaces.
In DE A 32 77 643 there is disclosed a domestic energy system using the Stirling principle and wherein the working gas enclosed in a working cylinder is thrust in alternating directions through a thermal regenerator by a displacement piston moved periodically between the dead centres. In this process gas is heated to a high temperature at the hot end of the cylinder by supply of heat and is cooled down at the other end to a low temperature. The so-called cold end of the working cylinder is connected through two non-return valves with two pressure vessels in which the maximum and minimum pressure of the system are steadily maintained. The working gas in these pressure vessels is used either to perform mechanical expansion work or to operate a regenerative cooling system which can operate both as a heat pump and as an air conditioning plant.
In this system the primary heating energy is converted into pressure energy and this latter is used for the production of power and as a driving means for heat pumps and cooling apparatus. This system involves too much labour, is too expensive and occupies too much space for use as an air conditioning plant for individual enclosed rooms.
In contrast therewith the present invention is intended to provide an air conditioning apparatus of the type mentioned at the beginning which will be suitable as a separate unit of equipment for individual rooms, effect heating with the minimum consumption of primary energy and enable cooling to be effected without recourse to any additional apparatus.
According to this invention there is provided air conditioning apparatus having a heat pump for the heating and cooling of closed rooms, the apparatus communicating both with the air in the room and with external air, wherein the heat pump comprises a free-piston Stirling heat pump driven with an oscillating movement by a drive unit, the air conditioning apparatus having separate ducts for stale air and fresh air and the air conditioning apparatus including means for altering the air supply or the direction of flow in order to enable the method of operation (cooling/heating) to be selected.
Embodiments according to the invention are shown as examples in the accompanying drawings. In the drawings: Figure 1 shows an air conditioning apparatus with a gas fired free piston Stirling engine operated under cooling and fed with fresh air.
Figure 2 shows a schematic diagram of the energy flow in the case of space cooling as shown in Figure 1, Figure 3 shows-the air conditioning apparatus of Figure 1 operated under heating and fed with fresh air, Figure 4 shows a schematic diagram of the energy flow in the case of space heating as shown in Figure 3, Figure 5 shows the air conditioning apparatus of Figure 1 operated under heating without a heat pump and without the supply of fresh air, Figure 6 shows an air conditioning apparatus driven by a linear electric motor when operated under cooling, Figure 7 shows a schematic diagram of the energy flow in the case of space cooling as shown in Figure 6, and Figure 8 shows a schematic diagram of the energy flow in the case of space heating.
Referring to the drawings, Stirling units of the kind used here are known per se. A unit of this type consists of a free-piston Stirling engine and a free-piston Stirling heat pump connected thereto, these units being situated in an enclosed fully sealed housing. The engine and the heat pump are interconnected via a power or working piston indirectly acting on the respective displacement apparatus of the engine and the heat pump. In the event of a temperature rise to 70"C, for example, on one side of the unit accompanied by a temperature drop to about 60"C in the centre, the two displacement devices and the working piston start to oscillate with a phase shift of about 90 so that the other end of the unit cools down. In the present example cooling is by about +5"C.
Figures 1 to 5 are schematic diagrams showing the configuration of air conditioning plant comprising a Stirling free-piston engine 10 and a Stirling free-piston heat pump 10a for the heating and cooling of individual rooms by air exchange and replacing the window units used hitherto which require electrical energy for cooling but additional heating power for heating. The air conditioning apparatus proposed here, however, does not require additional primary energy and is controlled by reversing the dampers 14, 15 from heating to cooling or vice versa. For example, 1 kW mech from the Stirling engine produces a heating performance of 6kW with a thermal coefficient of 1.5, in relation to the fuel, and a cooling performance of 2 kW with a performance figure of 0.5 in relation to the fuel.
Figures 1 and 2 show the plant operated for cooling with heat pump. The stale air 16 conveyed by the fan 11 out of the room is used for cooling the Stirling engine 10 and for the discharge of the pumped fresh air heat. A corresponding quantity of fresh air 17 flows to the internal compartment. In conjunction with the guide channel system the position assumed by the dampers 14 and 15 for the aforementioned operating state ensures that stale air 16 will not be mixed with fresh air 17. The combustion gases generated by the gas burner 12 are discharged through a separate draught flue 13. The oxygen required for the combustion is taken from the unheated used air.
Figures 3 and 4 provide schematic diagrams of the operation of the plant for heating with heat pump. In this case the fan 11 conveys fresh air 17 into the room. This air 17 is heated twice, firstly by taking in the heat pumped from the stale air 16 by the Stirling heat pump 10a and the energy-loss heat of the Stirling engine 10 which is introduced into the air guide channel 19 via heat baffles or cooling fins, and secondly by heat transmission from the combustion air via the heat exchangers 20. The combustion air is then discharged to the outside via the heat exchangers 20 and the draught flue 13. In the present case the gas burner 12 takes the required oxygen direct from the unheated fresh air 17. The blown heated fresh air displaces a corresponding quantity of stale air 16 from the room without being mixed with it.To avoid freezing, the receiving heat exchanger of the Stiriing heat pump 10a is designed to ensure that the stale air 16 will not be cooled to below +3"C even under continuous operation.
Figure 5 shows the operation of the plant for heating without heat pump. In this case the fan 11 takes in the stale air 16 from the interior of the room. The dampers 14 and 15 occupy the closed position for the supply of fresh air. The used air 16 taken in is heated by the energy-loss of the Stirling engine 10 and by the heat transmission from the combustion air in the heat exchanger 20 and flows back into the room. On the other hand, only very little of the surrounding air reaches the cold part of the heat pump 10a, which may thus freeze. The Stirling engine 10 thus changes over to idle motion. The cooled combustion gases are again discharged via the special draught flue 13. The type of operation described here is particularly suitable for the rapid pre-heating of excessively cooled rooms.
Figure 6 shows a version of the air conditioning plant which differs from that shown in Figures 1 to 5 and in which the drive is provided by a linear electric motor, the air guiding system being simplified and the arrows for the direction of flow being applicable to the cooling with heat pump method of operation.
The linear electric motor 31 and parts thereof and the Stirling engine 30 are mounted together in a closed housing which is filled, for example, with a working gas comprising helium at a pressure of 10 bar. The working piston of the Stirling heat pump 30 driven by the electric motor actuates the displacement device of the said pump. This latter thus has only two moving parts which are caused to perform a linear motion between gas cushions and almost without friction. The housing of the Stirling heat pump 30 is increased in surface area by ribs 10b for the purpose of heat exchange with the air.
If a room is to be cooled the electrically driven fan 32 taken in air from the room by suction as indicated by the arrows in Figure 1. This air, on exhaust, moves past the Stirling heat pump 30 situated in flow channel 36 and past the linear motor 31 thus absorbing waste heat therefrom. The corresponding quantity of fresh air now flows through the channel 37 into the room and in this process it cools down on the cold part 30a of the heat pump. This process takes place in such a manner that stale air and fresh air in the air conditioning plant are never mixed together at any point during the exchange. On cooling down the fresh air becomes dehumidified and the resulting condensation water is either conveyed into the open or, in tropical regions for example, is coilected. The cooling performance is now regulated by a room thermostat 34.This can be done in such a way, for example that the said thermostat varies the electrical voltage in the linear motor 31 or switches the latter on or off when a certain value is reached.
Furthermore, a temperature gauge 35 mounted on the cold part 30a of the Stirling heat pump 30 is connected to the room thermostat 34 and prevents the temperature of the said part from falling below freezing point. The maximum cooling performance is thus fixed at +5 C, for example. This means that the stale air likewise cannot cool down to below 5"C.
In itself control of the quantity of air by means of the fan 32 is unnecessary but it may nevertheless be of advantage for the air throughput to be regulated by a multi-stage switch 38.
If the room is to be heated then only the direction of rotation of the fan 32 is altered. As may be seen from Figure 6 of the drawings, in this case the flow arrows entered therein take exactly the opposite direction. This too is controlled by the room thermostat 34. It can naturally also be switched over by hand. The fan 32 now forces fresh air into the room which thus receives the stale air from the linear motor 31 and the Stirling heat pump 30. The quantity of room air corresponding to the live air flowing in passes to the outside as used air via the channel 37 and in this process the heat pumped for heating is given off in the cold part 30a of the heat pump. In this connection reference should also be made to Figures 7 and 8.
An air conditioning plant is thus provided which, particularly for the heating of individual rooms, is highly economic as regards both manufacture and servicing besides operating reliably and, since it only has two moving parts is practically free of friction and has a long service life and requires no maintenance. Even with decreasing heat absorption temperature the thermal coefficient remaining practically unchanged. This variant of the air conditioning plant is particularly suitable for use in zones in which the ambient air does not fali below freezing point but which nevertheless requires different degrees of heating.

Claims (11)

1. Air conditioning apparatus having a heat pump for the heating and cooling of closed rooms, the apparatus communicating both with the air in the room and with external air, wherein the heat pump comprises a free-piston Stirling heat pump driven with an oscillating movement by a drive unit, the air conditioning apparatus having separate ducts for stale air and fresh air and the air conditioning apparatus including means for altering the air supply or the direction of flow in order to enable the method of operation (cooling/heating) to be selected.
2. Air conditioning apparatus in accordance with Claim 1, wherein the drive unit for driving the Stirling heat pump comprises a gas-fuelled freepiston Stirling engine, manually adjustable dampers being provided for the selection of the method of operation.
3. Air conditioning apparatus in accordance with Claim 1, wherein the drive unit for driving the Stirling heat pump is a linear electric motor operated at mains frequency, a reversible fan being provided for the selection of the method of operation.
4. Air conditioning apparatus in accordance with Claim 2, wherein a separate draught flue is provided for the combustion gases for heating the Stirling engine.
5. Air conditioning apparatus in accordance with Claim 2 or 4, wherein the heat loss of the Stirling engine and the heat pumped by the Stirling heat pump are introduced into a separate air duct via heat baffles or cooling fins.
6. Air conditioning apparatus in accordance with any one of Claims 2, 4 and 5, wherein the receiving heat exchanger of the Stirling heat pump is arranged to ensure that even under continuous operation no air cooling occurs under +3"C.
7. Air conditioning apparatus in accordance with Claim 3, wherein the linear motor is provided with a room thermostat for the regulation of the voltage or on-off operation.
8. Air conditioning apparatus in accordance with Claim 3 or 7, wherein the heat-receiving cold part of the Stirling heat pump is provided with a temperature gauge.
9. Air conditioning apparatus in accordance with any one of Claims 3, 7 and 8 wherein the fan is provided with a multi-stage switch for regulating the rotation speed.
10. Air conditioning apparatus in accordance with any one of Claims 7 to 9 wherein the reversal of the direction of rotation of the fan is effected by the room thermostat.
11. Air conditioning apparatus as described herein and exemplified with reference to the drawings.
GB8610989A 1985-05-10 1986-05-06 Air conditioning apparatus Expired GB2177497B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853516975 DE3516975A1 (en) 1985-05-10 1985-05-10 Gas-fired heat pump for room heating and cooling
DE19853516961 DE3516961A1 (en) 1985-05-10 1985-05-10 Air-conditioning device for closed rooms

Publications (3)

Publication Number Publication Date
GB8610989D0 GB8610989D0 (en) 1986-06-11
GB2177497A true GB2177497A (en) 1987-01-21
GB2177497B GB2177497B (en) 1989-07-12

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB8610989A Expired GB2177497B (en) 1985-05-10 1986-05-06 Air conditioning apparatus

Country Status (2)

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FR (1) FR2581739B1 (en)
GB (1) GB2177497B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5477688A (en) * 1992-10-27 1995-12-26 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Automotive air conditioning apparatus
WO2017192612A1 (en) * 2016-05-02 2017-11-09 Wong Lee Wa Air conditioning and heat pump tower with energy efficient arrangement

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4996841A (en) * 1989-08-02 1991-03-05 Stirling Thermal Motors, Inc. Stirling cycle heat pump for heating and/or cooling systems
CN117128636A (en) * 2023-08-16 2023-11-28 江苏鼎视能源科技有限公司 Heat energy recovery device of air conditioner water cooling unit capable of partially recovering heat

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1532481A (en) * 1975-09-25 1978-11-15 Kalmovicz R Heat pumps
GB1547229A (en) * 1975-03-21 1979-06-06 Svenska Flaektfabriken Ab System for thermally treating air
GB1559293A (en) * 1975-07-31 1980-01-16 Gartner & Co J Air temperature control system for a room having an outside wall
GB2122335A (en) * 1982-06-15 1984-01-11 Wright Air Conditioning Limite Air conditioning system

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GB1252258A (en) * 1968-01-19 1971-11-03
ZA753251B (en) * 1974-06-07 1976-04-28 Research Corp Power piston actuated displacer piston driving means for free-piston stirling cycle type engine
DE2542728C3 (en) * 1975-09-25 1981-11-26 Burger, Manfred R., 8023 Pullach Heat pump for optional heating or cooling operation
DE2702765C2 (en) * 1977-01-24 1984-10-18 Hilti Ag, Schaan Sound-absorbing fastening element
GB2014720A (en) * 1978-01-04 1979-08-30 Bicc Ltd Air conditioning systems
US4458495A (en) * 1981-12-16 1984-07-10 Sunpower, Inc. Pressure modulation system for load matching and stroke limitation of Stirling cycle apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1547229A (en) * 1975-03-21 1979-06-06 Svenska Flaektfabriken Ab System for thermally treating air
GB1559293A (en) * 1975-07-31 1980-01-16 Gartner & Co J Air temperature control system for a room having an outside wall
GB1532481A (en) * 1975-09-25 1978-11-15 Kalmovicz R Heat pumps
GB2122335A (en) * 1982-06-15 1984-01-11 Wright Air Conditioning Limite Air conditioning system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
}STERLING ENGINES} READER & HOOPER. E & F N SPAN 1983 PARAGRAPHS 1.10 ON PAGE 151 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5477688A (en) * 1992-10-27 1995-12-26 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Automotive air conditioning apparatus
WO2017192612A1 (en) * 2016-05-02 2017-11-09 Wong Lee Wa Air conditioning and heat pump tower with energy efficient arrangement
US10612798B2 (en) 2016-05-02 2020-04-07 Lee Wa Wong Air conditioning and heat pump tower with energy efficient arrangement

Also Published As

Publication number Publication date
GB2177497B (en) 1989-07-12
GB8610989D0 (en) 1986-06-11
FR2581739B1 (en) 1990-05-11
FR2581739A1 (en) 1986-11-14

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 19920506