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EP0078849B1 - Regenerator-struktur für stirlingmotoren - Google Patents

Regenerator-struktur für stirlingmotoren Download PDF

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Publication number
EP0078849B1
EP0078849B1 EP19820902017 EP82902017A EP0078849B1 EP 0078849 B1 EP0078849 B1 EP 0078849B1 EP 19820902017 EP19820902017 EP 19820902017 EP 82902017 A EP82902017 A EP 82902017A EP 0078849 B1 EP0078849 B1 EP 0078849B1
Authority
EP
European Patent Office
Prior art keywords
regenerator
cycle
stirling
thermal
flow
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.)
Expired
Application number
EP19820902017
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English (en)
French (fr)
Other versions
EP0078849A4 (de
EP0078849A1 (de
Inventor
William Matthew Moscrip
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Individual
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Individual
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Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to AT82902017T priority Critical patent/ATE26154T1/de
Publication of EP0078849A1 publication Critical patent/EP0078849A1/de
Publication of EP0078849A4 publication Critical patent/EP0078849A4/de
Application granted granted Critical
Publication of EP0078849B1 publication Critical patent/EP0078849B1/de
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/04—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis the piston motion being transmitted by curved surfaces
    • 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
    • F02G1/044—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 having at least two working members, e.g. pistons, delivering power output
    • 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
    • F02G1/06—Controlling
    • 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
    • F02G2244/00—Machines having two pistons
    • F02G2244/02—Single-acting two piston engines
    • F02G2244/06—Single-acting two piston engines of stationary cylinder type
    • F02G2244/12—Single-acting two piston engines of stationary cylinder type having opposed pistons
    • 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
    • F02G2244/00—Machines having two pistons
    • F02G2244/50—Double acting piston machines

Definitions

  • This invention relates to Stirling-cycle engines, to other regenerative thermal machines, and more particularly to a new method for the construction of the regenerator element common to all such machines.
  • the new method involves the deliberate incorporation of certain anisotropic materials such as pyrolytic graphite to improve the heat transfer and storage performance characteristics of the regenerator. This will enhance the overall performance of regenerative thermal machines, especially those which embody a practical approximation to the well known Stirling thermo-dynamic cycle in the production of both mechanical power (i.e. prime movers, compressors, fluid pumps) and refrigeration (i.e. refrigerators, air conditioners, heat pumps, gas liquefiers).
  • mechanical power i.e. prime movers, compressors, fluid pumps
  • refrigeration i.e. refrigerators, air conditioners, heat pumps, gas liquefiers
  • a Stirling-cycle engine is a machine which operates on a closed regenerative thermo- dynamic cycle, with periodic compression and expansion of a gaseous working fluid at different temperature levels, and where the flow is controlled by volume changes in such a way as to produce a net conversion of heat to work, or vice versa.
  • the regenerator is a device which in prior art takes the form of a porous mass of metal in an insulated duct. This mass takes up heat from the working fluid during one part of the cycle, temporarily stores it within the machine until a later part of the cycle, and subsequently returns it to the working fluid prior to the start of the next cycle.
  • the regenerator may be thought of as an oscillatory thermodynamic sponge, alternately absorbing and releasing heat with complete reversibility and no loss.
  • thermodynamic system A reversible process for a thermodynamic system is an ideal process, which once having taken place, can be reversed without causing a change in either the system or its surroundings.
  • Regenerative processes are reversible in that they involve reversible heat transfer and storage; their importance derives from the fact that idealized reversible heat transfer is closely approximated by the regenerators of actual machines.
  • the Stirling engine is the only practical example of a reversible heat engine which can be operated either as a prime mover or as a heat pump.
  • DE-A-1501584 discloses a thermal regenerator filling mass comprising a roll of coated tape, wherein the coated tape comprises a layer of a material bonded to the tape, wherein the specific heat of the material forming a layer is high compared with that of the tape and the thermal conductivity of the tape is low compared with that of the said material.
  • the filling mass has a low thermal conductivity in the direction of flow of the medium through the regenerator.
  • US-A-3960204 discloses a low void volume regenerator for a Vuilleumier cryogenic cooler comprising a shell providing conduit for working fluid, a thermal mass packing said shell and configured to provide a passage therethrough with the highest practice ratio of exposed surface area to cross-sectional flow area and having a thermal conductivity in the direction of flow of said working liquid which is lower than that in the direction normal to the direction of said flow.
  • the invention comprises fundamental concepts and mechanical components which in combination enhance the operation yet lower the cost of Stirling-cycle machines, by means of the use of a regenerator which employs materials of construction which have anistropic symmetry to achieve anisotropic thermal conductivity and large specific heat capacity in a thermal mass having the highest practicable ratio of exposed surface area to cross-sectional flow area.
  • numeral 1 designates an idealized version of a two-piston Stirling-cycle prime mover.
  • a conceptually constant mass of pressurized gaseous working fluid occupies the working volume between the compression piston 2 and the expansion piston 3.
  • the total working volume is comprised by compression space 4, regenerator 5, and expansion space 6.
  • a portion of compression space 4 is continually cooled by cooler 7, while a portion of expansion space 6 is continually heated by heater 8.
  • Arrows 9 are intended to represent the input of heat by conduction, convection, or radiation. Escape of fluid from the working volume is prevented by the piston seals 10.
  • regenerator 5 yields stored heat to the working fluid as it is transferred to expansion space 6 with the volume remaining constant. The temperature and pressure rise to their maximum levels.
  • regenerator 5 recovers heat from the working fluid as it is transferred to compression space 4 with the volume remaining constant. The temperature and pressure return to the starting levels of the cycle.
  • FIG. 2(a) and FIG. 2(b) wherein the same complete cycle is presented in terms of the pressure-volume diagram and the temperature-entropy diagram for the working fluid.
  • the area under a curve on the P-V diagram is a representative measure of the mechanical work added to or removed from the system during the process.
  • the area under a curve on a T-S diagram is a measure of the heat transferred to or rejected from the working fluid during the process.
  • the regenerator is a device comprised by a thermal mass so arranged and deployed within a thermal machine that it takes up heat from the working fluid during one part of the cycle, temporarily stores it within the machine until a later part of the cycle, and subsequently returns it to the working fluid prior to the start of the next cycle.
  • My concept proposes the utilization of the unique physical property known as bulk anisotropy, which is displayed by certain well-known materials such as pyrolytic graphite and pyrolytic boron nitride, for the construction of an advanced regenerator in the manner illustrated by FIG. 3.
  • regenerator 20 is nothing more than an ordered or stacked assemblage of perforated sick elements 21 contained within a tubular duct 22 which possesses a comparitively low thermal conductivity.
  • the perforations 23, which may take many differnt forms, are designed so as to maximize the ratio of the perimeter of the perforation to the cross sectional area of the perforation.
  • the basic purpose of this approach is to maximize both the capacity and the rate of heat transfer with respect to the material of the regenerator, while at the same time to minimize working fluid flow losses and longitudinal thermal conductivity losses within the regenerator.
  • Pyrolytic graphite is a polycrystalline form of carbon having a high degree of molecular orientation. It possesses no binder, has a very high purity, and may exceed 98.5% of the theoretical density for carbon.
  • the material is usually produced by chemical vapor deposition onto a substrate which is maintained at an elevated temperature.
  • Such deposits possess great high temperature strength, exceptional thermo-physical properties, and phenomenal anisotropic symmetry. That is, they naturally and consistently exhibit one value for physical constants as measured in the plane of the deposit and compared to the value for the same constant as measured across the plane of the deposit.
  • the thermal conductivity of pyrolytic graphite in the plane of the deposit is about equal to that of copper at room temperature (4.2 watts/cm 2 /°C/cm); but the conductivity across the plane of the deposit is reduced by almost 200 to 1 (0.025 watts/cm2l°C/cm).
  • the corresponding values at 1000°C are know to be similarly anomalous (1.25 watts/cm2/°C/cm and 0.012 watts/cm2/°C/ cm) and the value of the specific heat at 750°C (1182°F) is known to be approximately 0.45 cal/g/ °C, which is among the highest values for all structural engineering materials.
  • a number of perforated disks 21 may be made of this or similar material to have a comparatively large transaxial thermal conductivity (i.e., in the plane of the disk), yet to have a comparatively small axial- thermal conductivity (i.e., across the thickness of the disk).
  • the indicated assemblage of said perforated disks 21 would therefore comprise, when placed within the insulative cyclindrical container 22, a remarkably efficient regenerator.
  • Pyrolytic graphite also has a great difference in linear thermal expansion coefficients between the directions within the plane of the deposit and the direction perpendicular to the plane of the deposit.
  • the average coefficient of linear thermal expansion from room temperature to 1000°C is know to be 1.3 x 10 6 cm/cm/C in the plane of deposit and 22.0 x 10-rcm/cmPC across the plane of deposit.
  • the latter value should be matched by the wall of the containing vessel, in order to preclude or minimize thermal stresses; inevitably, it is reasonably close to that of many structural alloys of interest, including certain alloys of aluminum, manganese, and copper.
  • the closed cycle Stirling prime mover operates solely on the basis of the difference in temperature in the working fluid between the hot expansion space and the cold compression space, the development of useful power output is not specific to the source of heat available for use. Therefore, the design of the heat source can be any one of a large variety of possible types.
  • a rather simple combustion system can be produced, for example, which will cleanly and efficiently burn various kinds of both liquid fuels and gaseous fuels without any modification whatsoever.
  • a single prime mover may be made to operate on regular or premium gasoline, diesel oil, alcohol, crude oil, lubricating oil, olive oil, vegetable oil, propane, butane, natural gas, and synthetic coal gas.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)

Claims (2)

1. Regenerator-Struktur zur Verwendung in Stirling-Kolbenwärmekraftsmaschinen, aufweisend einen gasdichten, einen Leitkanal für ein Maschinenarbeitsfluid bildenden Kolbenraum, eine in diesem Raum vorgesehene thermische Füllkörpermasse, die so strukturiert ist, daß sie durch diesen Raum einen Durchgang mit dem höchstmöglich praktikablen Verhältnis von exponierter Oberfläche zu Querschnittsströmungsfläche liefert und in Strömungsrichtung dieses Machinenarbeitsfluids eine thermische Leitfähigkeit aufweist, die geringer ist als die in der zu dieser Strömungsrichtung senkrechten Richtung, dadurch gekennzeichnet, daß die thermische Masse aus anisotrope Eigenschaften aufweisendem Material zusammengesetzt ist, welche das höchstmöglich praktikable Verhältnis von thermischer Leitfähigkeit senkrecht zur Strömungsrichtung durch diese Masse zu thermischer Leitfähigkeit in dieser Strömungsrichtung liefern.
2. Regenerator-Struktur nach Anspruch 1, in welcher diese Masse aus einer Gruppe, die pyrolytisches Graphit und pyrolytisches Bornitrid umfaßt, aus gewähltem Material zusammengesetzt ist.
EP19820902017 1981-05-14 1982-05-14 Regenerator-struktur für stirlingmotoren Expired EP0078849B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82902017T ATE26154T1 (de) 1981-05-14 1982-05-14 Regenerator-struktur fuer stirlingmotoren.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US26369181A 1981-05-14 1981-05-14
US263691 1981-05-14

Publications (3)

Publication Number Publication Date
EP0078849A1 EP0078849A1 (de) 1983-05-18
EP0078849A4 EP0078849A4 (de) 1985-02-28
EP0078849B1 true EP0078849B1 (de) 1987-03-25

Family

ID=23002858

Family Applications (4)

Application Number Title Priority Date Filing Date
EP19820902017 Expired EP0078849B1 (de) 1981-05-14 1982-05-14 Regenerator-struktur für stirlingmotoren
EP82902018A Expired EP0078850B1 (de) 1981-05-14 1982-05-14 Komponenten für die wärmeübertragung bei stirlingmotoren
EP19820902015 Expired EP0078847B1 (de) 1981-05-14 1982-05-14 Thermodynamische arbeitsmedien für stirlingmotoren
EP19820902016 Expired EP0078848B1 (de) 1981-05-14 1982-05-14 Mechanischer aufbau von stirlingmotoren

Family Applications After (3)

Application Number Title Priority Date Filing Date
EP82902018A Expired EP0078850B1 (de) 1981-05-14 1982-05-14 Komponenten für die wärmeübertragung bei stirlingmotoren
EP19820902015 Expired EP0078847B1 (de) 1981-05-14 1982-05-14 Thermodynamische arbeitsmedien für stirlingmotoren
EP19820902016 Expired EP0078848B1 (de) 1981-05-14 1982-05-14 Mechanischer aufbau von stirlingmotoren

Country Status (3)

Country Link
EP (4) EP0078849B1 (de)
DE (4) DE3278913D1 (de)
WO (4) WO1982004098A1 (de)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BG63221B1 (bg) 1997-03-14 2001-06-29 Боян БАХНЕВ Гърбичен двигател
US6282895B1 (en) * 1997-07-14 2001-09-04 Stm Power, Inc. Heat engine heater head assembly
US6668809B2 (en) * 2001-11-19 2003-12-30 Alvin Lowi, Jr. Stationary regenerator, regenerated, reciprocating engine
HRP20040269B1 (en) * 2004-03-19 2010-03-31 Rak Miroslav Thermal hydro-machine on hot gas with recirculation
CN101988443A (zh) * 2010-10-27 2011-03-23 靳北彪 非共轭零距高低温热源热气机

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Publication number Priority date Publication date Assignee Title
US766410A (en) * 1903-11-19 1904-08-02 Marshall Alger Motor.
US1229009A (en) * 1915-06-07 1917-06-05 Joseph F Allison Pumping-engine.
US2616668A (en) * 1947-05-30 1952-11-04 Hartford Nat Bank & Trust Co Regenerator
GB715594A (en) * 1951-11-27 1954-09-15 Philips Nv Improvements in thermal regenerators
BE669418A (de) * 1964-09-11
DE1451156A1 (de) * 1964-09-16 1969-02-06 Linde Ag Waerme- und Stoffaustauschelement
US3403508A (en) * 1966-12-09 1968-10-01 Donald A. Kelly Stirling cycle engine with wave-cam means interconnecting pistons and drive shaft thereof
US3385051A (en) * 1967-02-10 1968-05-28 Donald A. Kelly Stirling cycle engine with two wave cam means, two piston banks and driveshaft
US3407593A (en) * 1967-04-10 1968-10-29 Donald A. Kelly Reciprocating stirling cycle engine with dual wave cam drive
US4084376A (en) * 1969-10-30 1978-04-18 U.S. Philips Corporation Heating system
US3950947A (en) * 1969-12-24 1976-04-20 U.S. Philips Corporation Hot-gas machine comprising a heat transfer device
US3678992A (en) * 1970-08-06 1972-07-25 Philips Corp Thermal regenerator
US3710572A (en) * 1971-01-04 1973-01-16 Textron Inc Thrust chamber
US3913666A (en) * 1972-03-20 1975-10-21 Peter Bayliss Heat resistant wall construction
US3994136A (en) * 1975-07-03 1976-11-30 Josam Manufacturing Co. Hot gas engine
US3999388A (en) * 1975-10-08 1976-12-28 Forenade Fabriksverken Power control device
US4030297A (en) * 1976-06-28 1977-06-21 Ford Motor Company Hydrogen compression system for Stirling engine power control
NL7705363A (nl) * 1977-05-16 1978-11-20 Philips Nv Heetgasmotor.
US4183213A (en) * 1977-07-18 1980-01-15 Ford Motor Company Heat exchanger for Stirling engine
DE2820526C2 (de) * 1978-05-11 1982-04-22 Schneider, Christian, Dipl.-Ing., 8650 Kulmbach Heißgas-Hubkolbenmotor mit elektromagnetisch angetriebenem Verdränger
SE417448B (sv) * 1979-06-19 1981-03-16 Cmc Ab Modul for uppbyggnad av en dubbelverkande, fyrcylindrig stirling-motor

Also Published As

Publication number Publication date
EP0078847B1 (de) 1987-03-04
DE3279652D1 (en) 1989-06-01
DE3275848D1 (en) 1987-04-30
WO1982004101A1 (en) 1982-11-25
EP0078848A1 (de) 1983-05-18
DE3275577D1 (en) 1987-04-09
EP0078847A1 (de) 1983-05-18
EP0078848B1 (de) 1989-04-26
EP0078850B1 (de) 1988-08-17
WO1982004099A1 (en) 1982-11-25
EP0078847A4 (de) 1984-12-11
EP0078848A4 (de) 1984-12-11
EP0078850A4 (de) 1985-02-28
WO1982004098A1 (en) 1982-11-25
EP0078849A4 (de) 1985-02-28
EP0078850A1 (de) 1983-05-18
EP0078849A1 (de) 1983-05-18
WO1982004100A1 (en) 1982-11-25
DE3278913D1 (en) 1988-09-22

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