GB1581749A

GB1581749A – Stirling cycle heat engines
– Google Patents

GB1581749A – Stirling cycle heat engines
– Google Patents
Stirling cycle heat engines

Download PDF
Info

Publication number
GB1581749A

GB1581749A
GB239077A
GB239077A
GB1581749A
GB 1581749 A
GB1581749 A
GB 1581749A
GB 239077 A
GB239077 A
GB 239077A
GB 239077 A
GB239077 A
GB 239077A
GB 1581749 A
GB1581749 A
GB 1581749A
Authority
GB
United Kingdom
Prior art keywords
engine
liquid
output
displacement
pressure
Prior art date
1977-01-20
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.)

Expired

Application number
GB239077A
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.)

UK Atomic Energy Authority

Original Assignee
UK Atomic Energy Authority
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.)
1977-01-20
Filing date
1977-01-20
Publication date
1980-12-17

1977-01-20
Application filed by UK Atomic Energy Authority
filed
Critical
UK Atomic Energy Authority

1977-01-20
Priority to GB239077A
priority
Critical
patent/GB1581749A/en

1977-04-07
Priority to IN535/CAL/77A
priority
patent/IN145853B/en

1980-12-17
Publication of GB1581749A
publication
Critical
patent/GB1581749A/en

Status
Expired
legal-status
Critical
Current

Links

Espacenet

Global Dossier

Discuss

Classifications

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

Description

(54) IMPROVEMENTS IN OR RELATING TO STIRLING
CYCLE HEAT ENGINES
(71) We, UNITED KINGDOM ATO
MIC ENERGY AUTHORITY of 11
Charles II Street, London, SW1Y 4QP, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
This invention relates to a Stirling cycle heat engine having hot and cold variable volume chambers intercommunicating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid. An example of such a Stirling cycle engine is described in co-pending application No.
14911/76 (Serial No. 1581748) which in
Claim 1 describes a Stirling cycle engine comprising hot and cold variable volume chambers intercommunicating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from the engine, wherein the hot and cold variable volume chambers are arranged one within the other and are thermally insulated from one another.
According to one aspect of the present invention, in a Stirling cycle heat engine having hot and cold variable volume chambers intercommunicating through a regenerator and adapted to contain a working gas a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid, the output means is resiliently biased in a manner to resist said displacement so as to enable the engine to operate at a predetermined mean pressure of the working gas.
According to another aspect of the present invention, in a Stirling cycle heat engine having hot and cold variable volume chambers intercommunicating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in, at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid, the output means is resiliently biased in a manner to assist said displacement and enable the engine to operate at a predetermined mean pressure of the working gas.
Preferably, the output means comprises a flexible obturator means, and the resilient bias is provided by gas pressure. The obturator means may be adapted to provide a portion of a wall of a variable volume pumping chamber of a pumping means.
The resiliently biased output means enables the engine to be pressurised by use of a higher mean gas pressure with a consequent higher output head from the engine compared with that of a similar but unpressurised engine.
The invention will now be described by way of example only with reference to the accompanying drawings in which:
Figure 1 shows in median section a diagrammatic representation of a Stirling cycle heat engine;
Figure 2 shows to an enlarged scale that portion of Figure 1 within the circle ‘it’; and
Figure 3 shows in fragmentary median section. and to an enlarged scale, an alternative output means incorporated in the engine of Figure 1.
Referring now to Figure 1, the single
Fluidyne (Registered Trade Mark) Stirling cycle heat engine of Figure 1 is similar to the engine of Figure 1 of the afore-mentioned co-pending application No. 14911/76 (Serial
No. 1581748), to which reference is directed. The engine is of circular form in section, and comprises an aluminium cylindrical closed tank 1 having a chamber la, partially filled with a liquid such as mineral oil, and having a flow barrier 2 of hollow cylindrical form disposed substantially concentrically therein, the flow barrier 2 being formed by a thermal insulating core 2a of magnesia supported by an aluminium liner 2b.
The flow barrier is made shorter than the inside height of the tank 1 so as to provide a space for a regenerator 3 between the top of the barrier 2 and the top of the tank 1, and leave a port for liquid in the form of a flow space 5 between the bottom of the barrier 2 and the base 6 of the tank 1.
The flow barrier 2 divides the tank 1 into an outer annular chamber 10 and an inner cylindrical chamber 11 communicating through the regenerator 3 and the flow space 5. The space above the liquid is filled with a working gas such as air, hydrogen or helium at a predetermined mean pressure, and provides a cold chamber 12 in the annular chamber 10 and a hot chamber 13 in the inner chamber 11 of the engine.
An outlet 15 is connected at one end to the base of the tank 1 and is U-shaped so as to extend upwardly parallel to the chambers 10 and 11 respectively. The other end 15a of the output tube 15 is closed and of reduced diameter, and means are provided at the closed end l5a for deriving an output from the displacement of the liquid in the tank 1 and shown in greater detail in Figure 2 to which reference is now made.
In Figure 2, flexible obturators in the form of two Philips Rollsock seals 101 and 102 respectively are disposed axially in series within the output tube 15 in opposed relationship to define a pumping space 106 therebetween, and are rigidly connected together by a rod 103 arranged to slide in a guide 104 held by spider arms 105 extending from the wall of the output tube 15. A gas such as air is trapped in the end space 107 defined between the closed end l5a of the output tube 15 and the adjacent Rollsock seal 102.
Each Rollsock seal 101 or 102 respectively comprises a flexible Neoprene or VITON (Registered Trade Mark) gaiter 101a or 1()2a respectively attached at one end to a piston portion lOIb or 1()2b respectively and at the other end thereof to the inside of the output tube 15 or closed end 15a respectively. Because of the difference in swept volume between the piston portion 101b and 102b during displacement thereof a change in volume is effected in the pumping space 106.
A branch tube 110 joined to the output tube 15 to connect with the pumping space 106, is connectable to a pump (not shown).
The pumping space 106 and branch tube 110 may contain either a gas, such as air, or a liquid, to operate the pump from volume changes in the pumping space 106 caused by displacement of the liquid from the tank 1, in operation of the engine, displacing the
Rollsock seals 101 and 102.
The pressures of the liquid and gas acting on the Rollsock seals 101 and 102 respectively are not equal, the larger Rollsock seal 101 having a lower liquid pressure acting on it, but the forces (i.e. the pressure x the effective area of the Rollsock seals 101 and 102) acting on them are arranged to be equal as shown in Figure 2 in an equilibrium position of the engine so that two equal but opposite forces are acting on the rod 103.
Any change in pressure of the liquid acting on the larger Rollsock seal 101 from pressure changes in the working gas in the tank 1 during operation of the engine, creates a difference in the forces acting across the Rollsock seals 101 and 102 and therefore, causes displacement thereof.
In operation of the engine as explained more fully in British Patent Specification
No. 1329567, and co-pending application
No. 14911/76 (Serial No. 1581748), on heat being applied to the hot chamber 13 by a heat source (not shown) the gas therein expands causing oscillation of the liquid and oscillation of the gas betwen the cold and hot chambers 12 and 13 respetively through the regenerator 3, heat being extracted from the gas by the regenerator 3 when the gas flows towards the cold chamber 12 and absorbed from the regenerator 3 by the gas when it flows towards the hot chamber 13.
Displacement of the liquid in the tank 1 as a result of the pressure changes in the gas above the liquid causes corresponding displacement of the liquid in the output tube 15 and, therefore, upward displacement of the lower Rollsock seal 101 and the upper
Rollsock seal 102. Because of the difference in cross-sectional area swept by the two
Rollsock seals 101 and 102, the change in volume of the pumping space 106 causes displacement of liquid or gas from the pumping space 106 through the branch tube 110 to operate the pump.
Instead of being coupled to a pump, the gas or liquid in the pumping space 106 may be arranged, for example, to displace a diaphragm, another Rollsock seal, or a similar pressure sensitive device (not shown) to derive a direct mechanical output therefrom.
It will be understood that the Rollsock seals 101 and 102 may be replaced by devices capable of performing a similar function, and that alternative materials may be used in the construction of the engine as suggested in co-pending application No.
14911/76 (Serial No. 1581748).
The predetermined mean pressure of the gas in the space above the liquid in the tank 1 is selected to provide a desired output head from the engine, a mean gas pressure in the range 1 – 3 atmospheres being preferred, the pressure of the gas in the closed end 15a of the output tube 15 being correspondingly selected so as to balance the displacement of the Rollsock seals 101 and 102 against the aforesaid predetermined pressure.
The invention has been described in relation to the use of an output means at the end of the output tube 15 remote from the tank 1 since in this position it is more accessible for servicing, but if desired it can be incorporated elsewhere, for example, as shown in Figure 3 which also shows an alternative form of output means according to the invention.
Referring now to Figure 3, the base 6 of the tank 1 is provided with an internal standpipe 20 having an upper end 21 provided with a plurality of holes 22. A flexible obturator in the form of a diaphragm 23, for
Neoprene or VITON (R.T.M.) reinforced with a rayon fabric, is clamped to the upper end 21 by an aluminium annular plate 24 using studs (not shown) welded to the upper end 21. A shouldered boss 28 of aluminium is bonded to the underside of the diaphragm 23 to provide an anchorage for one end of a compression spring 29 having a required resilience to urge the diaphragm 23 against the end 21. An outlet tube 30 containing a liquid such as water and having a flange 31 is secured to the outside of the base 6 of the tank 1 using studs (not shown) welded to the base 6, and a sealing gasket 32.The flange 31 extends across the end of the outlet tube 30 and is shaped to provide a central boss 35, for locating the other end of the spring 29 and has a plurality of holes 36 for fluid flow therethrough. The outlet tube 30 has an elbow portion 37 having an unequal outlet 38 which continues in the same manner as the outlet tube 15 on Figure 1 but does not have the arrangement of Rollsock seals as shown in Figure 2.
In operation, the diaphragm 23 is deflected downwardly when the force exerted by the pressure of the liquid in the tank l on the diaphragm 23 exceeds the predetermined pressure on it exerted by the spring 29, and causes a corresponding displacement of the liquid in the outlet tube 30 from which an output from the engine may be derived.
The position of the diaphragm 23 permits the use of two liquids having different properties, each selected for the function it has to perform. for example oil in the tank 1 and water in the output tube 30. or alternatively the diaphragm 23 may be directly coupled to a mechanical member (not shown) of a mechanical device for deriving an output.
The diaphragm 23 may be made from suitable alternative materials such as plastics or a metal, and alternative springs 29 may be used, for example, a flat spring bonded to the underside of the diaphragm 23.
The invention may be incorporated in alternative forms Stirling cycle heat engines, for example, the engines described in British Patent Specification No. 1,329,567 and co-pending applications Nos. 46797/75 (Serial No. 1568057) and 14911/76 (Serial No.
1581748).
It will be understood that although the invention has been described in relation to the use of an output means which is resiliently biased to resist the displacement of the liquid in the liquid system, the direction of the resilient bias may be reversed so that the bias assists the liquid displacement, for example, to enable a predetermined mean pressure of the working gas below atmospheric pressure to be used.
WHAT WE CLAIM IS:
1. A Stirling cycle heat engine having hot and cold variable chambers intercommuncating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid, wherein the output means is resiliently biased in a manner to resist said displacement so as to enable the engine to operate at a predetermined mean pressure of the working gas.
2. A Stirling cycle heat engine having hot and cold variable volume chambers intercommunicating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid, wherein the output means is resiliently biased in a manner to assist said displacement and enable the engine to operate at a predetermined mean pressure of the working gas.
3. An engine as claimed in Claim 1, wherein the predetermined mean pressure is 1 to 3 atmospheres.
4. An engine as claimed in Claim 2, wherein the predetermined mean pressure is below atmospheric pressure.
5. An engine as claimed in any one of the preceding Claims, wherein the output means comprises a flexible obturator means.
6. An engine as claimed in any one of the preceding Claims, wherein the resilient bias is provided by gas pressure.
7. An engine as claimed in any one of
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (13)

**WARNING** start of CLMS field may overlap end of DESC **.
The predetermined mean pressure of the gas in the space above the liquid in the tank 1 is selected to provide a desired output head from the engine, a mean gas pressure in the range 1 – 3 atmospheres being preferred, the pressure of the gas in the closed end 15a of the output tube 15 being correspondingly selected so as to balance the displacement of the Rollsock seals 101 and 102 against the aforesaid predetermined pressure.
The invention has been described in relation to the use of an output means at the end of the output tube 15 remote from the tank 1 since in this position it is more accessible for servicing, but if desired it can be incorporated elsewhere, for example, as shown in Figure 3 which also shows an alternative form of output means according to the invention.
Referring now to Figure 3, the base 6 of the tank 1 is provided with an internal standpipe 20 having an upper end 21 provided with a plurality of holes 22. A flexible obturator in the form of a diaphragm 23, for
Neoprene or VITON (R.T.M.) reinforced with a rayon fabric, is clamped to the upper end 21 by an aluminium annular plate 24 using studs (not shown) welded to the upper end 21. A shouldered boss 28 of aluminium is bonded to the underside of the diaphragm 23 to provide an anchorage for one end of a compression spring 29 having a required resilience to urge the diaphragm 23 against the end 21. An outlet tube 30 containing a liquid such as water and having a flange 31 is secured to the outside of the base 6 of the tank 1 using studs (not shown) welded to the base 6, and a sealing gasket 32.The flange 31 extends across the end of the outlet tube 30 and is shaped to provide a central boss 35, for locating the other end of the spring 29 and has a plurality of holes 36 for fluid flow therethrough. The outlet tube 30 has an elbow portion 37 having an unequal outlet 38 which continues in the same manner as the outlet tube 15 on Figure 1 but does not have the arrangement of Rollsock seals as shown in Figure 2.
In operation, the diaphragm 23 is deflected downwardly when the force exerted by the pressure of the liquid in the tank l on the diaphragm 23 exceeds the predetermined pressure on it exerted by the spring 29, and causes a corresponding displacement of the liquid in the outlet tube 30 from which an output from the engine may be derived.
The position of the diaphragm 23 permits the use of two liquids having different properties, each selected for the function it has to perform. for example oil in the tank 1 and water in the output tube 30. or alternatively the diaphragm 23 may be directly coupled to a mechanical member (not shown) of a mechanical device for deriving an output.
The diaphragm 23 may be made from suitable alternative materials such as plastics or a metal, and alternative springs 29 may be used, for example, a flat spring bonded to the underside of the diaphragm 23.
The invention may be incorporated in alternative forms Stirling cycle heat engines, for example, the engines described in British Patent Specification No. 1,329,567 and co-pending applications Nos. 46797/75 (Serial No. 1568057) and 14911/76 (Serial No.
1581748).
It will be understood that although the invention has been described in relation to the use of an output means which is resiliently biased to resist the displacement of the liquid in the liquid system, the direction of the resilient bias may be reversed so that the bias assists the liquid displacement, for example, to enable a predetermined mean pressure of the working gas below atmospheric pressure to be used.
WHAT WE CLAIM IS:
1. A Stirling cycle heat engine having hot and cold variable chambers intercommuncating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid, wherein the output means is resiliently biased in a manner to resist said displacement so as to enable the engine to operate at a predetermined mean pressure of the working gas.

2. A Stirling cycle heat engine having hot and cold variable volume chambers intercommunicating through a regenerator and adapted to contain a working gas, a liquid system in which liquid in at least one of the chambers is displaceable for varying the gas volume in the chambers, and means to derive an output from displacement of the liquid, wherein the output means is resiliently biased in a manner to assist said displacement and enable the engine to operate at a predetermined mean pressure of the working gas.

3. An engine as claimed in Claim 1, wherein the predetermined mean pressure is 1 to 3 atmospheres.

4. An engine as claimed in Claim 2, wherein the predetermined mean pressure is below atmospheric pressure.

5. An engine as claimed in any one of the preceding Claims, wherein the output means comprises a flexible obturator means.

6. An engine as claimed in any one of the preceding Claims, wherein the resilient bias is provided by gas pressure.

7. An engine as claimed in any one of
Claims 1 to 5, wherein the resilient bias is provided by spring means.

8. An engine as claimed in Claim 5, wherein the obturator means is adapted to provide a portion of a wall of a variable volume pumping chamber of a pumping means.

9. An engine as claimed in Claim 8, wherein the obturator means comprises two flexible obturators of differing crosssectional areas disposed in series relationship and secured axially together so as to have the same axial displacement but differ ing swept volumes, and the variable volume pumping chamber is provided by the space between the obturators.

10. An engine as claimed in Claim 5, wherein the flexible obturator means is adapted on the output side thereof for connection to a mechanical member for driving a mechanical device from displacement of the obturator means.

11. An engine as claimed Claim 5, wherein the flexible obturator means is disposed in a duct and has the liquid system on one side thereof and another liquid on the output side thereof so as to provide an output from displacement of the another liquid.

12. An engine substantially as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.

13. An engine substantially as hereinbefore described with reference to Figure 1 of the accompanying drawings as modified by
Figure 3.
Reference has been directed in pursuance of section 9, subsection (1) of the Patents Act 1949, to patent No. 1329567

GB239077A
1976-04-12
1977-01-20
Stirling cycle heat engines

Expired

GB1581749A
(en)

Priority Applications (2)

Application Number
Priority Date
Filing Date
Title

GB239077A

GB1581749A
(en)

1977-01-20
1977-01-20
Stirling cycle heat engines

IN535/CAL/77A

IN145853B
(en)

1976-04-12
1977-04-07

Applications Claiming Priority (1)

Application Number
Priority Date
Filing Date
Title

GB239077A

GB1581749A
(en)

1977-01-20
1977-01-20
Stirling cycle heat engines

Publications (1)

Publication Number
Publication Date

GB1581749A
true

GB1581749A
(en)

1980-12-17

Family
ID=9738706
Family Applications (1)

Application Number
Title
Priority Date
Filing Date

GB239077A
Expired

GB1581749A
(en)

1976-04-12
1977-01-20
Stirling cycle heat engines

Country Status (1)

Country
Link

GB
(1)

GB1581749A
(en)

Cited By (2)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

DE4429659A1
(en)

*

1994-08-20
1996-02-22
Eckhart Weber

Flat collector stirling machine

CN107396638A
(en)

*

2015-03-25
2017-11-24
太阳轨道股份有限公司
Stirling engine and the method using Stirling engine

1977

1977-01-20
GB
GB239077A
patent/GB1581749A/en
not_active
Expired

Cited By (4)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

DE4429659A1
(en)

*

1994-08-20
1996-02-22
Eckhart Weber

Flat collector stirling machine

CN107396638A
(en)

*

2015-03-25
2017-11-24
太阳轨道股份有限公司
Stirling engine and the method using Stirling engine

US20180252183A1
(en)

*

2015-03-25
2018-09-06
Sun Orbit Gmbh
Stirling engine and method of using a stirling engine

US10774784B2
(en)

*

2015-03-25
2020-09-15
Sun Orbit Gmbh
Stirling engine with a membrane connecting the piston to the cylinder of the Stirling engine and a method of using this Stirling engine

Similar Documents

Publication
Publication Date
Title

US4352269A
(en)

1982-10-05

Stirling engine combustor

US4381648A
(en)

1983-05-03

Stirling cycle apparatus with metal bellows seal

KR101304186B1
(en)

2013-09-06

Pressure accumulator, in particular pulsation damper

US3828558A
(en)

1974-08-13

Means and method for prevention of piston creep in free-piston reciprocating device

JP3786959B2
(en)

2006-06-21

Centering system with one-way valve for free piston machines

US4638633A
(en)

1987-01-27

External combustion engines

US9677794B2
(en)

2017-06-13

Heat pump with electromechanically-actuated displacers

GB2364365A
(en)

2002-01-23

Thermostatic valve having an electrically heatable operating element

US4967558A
(en)

1990-11-06

Stabilized free-piston stirling cycle machine

US4769992A
(en)

1988-09-13

Reciprocation apparatus with sealing mechanism

GB1581749A
(en)

1980-12-17

Stirling cycle heat engines

US3415054A
(en)

1968-12-10

Demonstration model of hot air motor and heat pump

US4380152A
(en)

1983-04-19

Diaphragm displacer Stirling engine powered alternator-compressor

US4594057A
(en)

1986-06-10

Injector pump

CA1187294A
(en)

1985-05-21

Hermetic resonant piston stirling engine compressor alternator having hydraulic coupling diaphragm

US4382363A
(en)

1983-05-10

Stirling engine displacer suspension system

KR20070043780A
(en)

2007-04-25

Fluidic oscillator

US4870821A
(en)

1989-10-03

Reciprocation apparatus with sealing mechanism

US4361008A
(en)

1982-11-30

Stirling engine compressor with compressor and engine working fluid equalization

US5109673A
(en)

1992-05-05

Relative gas spring configuration free-piston stirling cycle system

US5485726A
(en)

1996-01-23

Pressure control apparatus for stirling module

GB2298903A
(en)

1996-09-18

Stirling engine with sprung displacer and flexible diaphragm

US3088487A
(en)

1963-05-07

High pressure valve assembly

GB2143021A
(en)

1985-01-30

Cryogenic refrigerator

US4372115A
(en)

1983-02-08

Oil backed Stirling engine displacer diaphragm

Legal Events

Date
Code
Title
Description

1981-03-04
PS
Patent sealed

1983-11-09
PCNP
Patent ceased through non-payment of renewal fee

Download PDF in English

None