EP0247935A1 - Feeding method for a Joule-Thomson cooler and cooling device for carrying it out - Google Patents

Feeding method for a Joule-Thomson cooler and cooling device for carrying it out Download PDF

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Publication number
EP0247935A1
EP0247935A1 EP87401167A EP87401167A EP0247935A1 EP 0247935 A1 EP0247935 A1 EP 0247935A1 EP 87401167 A EP87401167 A EP 87401167A EP 87401167 A EP87401167 A EP 87401167A EP 0247935 A1 EP0247935 A1 EP 0247935A1
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EP
European Patent Office
Prior art keywords
working fluid
flow rate
orifice
fluid
cooling
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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
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EP87401167A
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German (de)
French (fr)
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EP0247935B1 (en
Inventor
Alain Faure
Serge Reale
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Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Publication of EP0247935A1 publication Critical patent/EP0247935A1/en
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    • 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
    • F25B9/02—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point using Joule-Thompson effect; using vortex effect
    • 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
    • F25B2309/02—Gas cycle refrigeration machines using the Joule-Thompson effect
    • F25B2309/022—Gas cycle refrigeration machines using the Joule-Thompson effect characterised by the expansion element

Definitions

  • the present invention relates to a method for supplying a Joule-Thomson cooler comprising a high pressure line which ends in a pressure relief port, and a low pressure discharge circuit in heat exchange relation with the high line pressure and into which the expansion orifice opens, and more particularly to a method of the type in which the high pressure pipe is successively supplied with a starting fluid and then with a working fluid.
  • the object of the invention is to allow lower temperatures to be obtained in a very short time than has hitherto been possible.
  • the subject of the invention is a process of the aforementioned type, characterized in that the working fluid is used first at a high flow rate, then its flow rate is suddenly reduced to finish the cooling phase of the cooler .
  • the flow is reduced by masking the expansion orifice with a surface allowing a leakage passage to remain at the periphery of the orifice; - the flow rate of the working fluid is reduced in a ratio at least equal to 10; - We go from the starting fluid to the working fluid when the cooling speed provided by the first becomes lower than the cooling speed provided by the second.
  • the invention also relates to a cooling device intended to implement the method defined above.
  • This device of the type comprising a first source of starting fluid under a first high pressure, a second source of working fluid under a second high pressure, a Joule-Thomson cooler comprising a high pressure conduit which ends in a pressure relief port and a low pressure discharge circuit in heat exchange relationship with the high pressure pipe and into which the expansion orifice opens, and switching means for connecting the high pressure pipe first to the first source and then to the second source, is characterized in that it comprises throttling means for abruptly reducing the flow rate flowing in the high pressure pipe.
  • the throttling means comprise a shutter movable from a first position where the expansion orifice is free to a second position where this orifice is masked by a surface allowing the periphery of the orifice to be substituted an escape route.
  • the reservoir 1 shown in FIG. 1 is divided into two unequal chambers by a transverse partition 2: a downstream auxiliary chamber 3 containing a starting fluid with Joule-Thomson effect which is large but relatively not very volatile, for example argon, under a first high pressure which can be of the order of 700 bars, and an upstream main chamber 4 containing a more volatile working fluid and with a lesser Joule-Thomson effect, for example nitrogen, within one second high pressure at most equal to the first high pressure, for example of the order of 400 bars.
  • a transverse partition 2 a downstream auxiliary chamber 3 containing a starting fluid with Joule-Thomson effect which is large but relatively not very volatile, for example argon, under a first high pressure which can be of the order of 700 bars, and an upstream main chamber 4 containing a more volatile working fluid and with a lesser Joule-Thomson effect, for example nitrogen, within one second high pressure at most equal to the first high pressure, for example of the order of 400 bars.
  • the partition 2 is pierced with an orifice 5 masked by a piece of foil 6 applied to the front face of the partition.
  • From the downstream chamber 3 leaves an outlet pipe 9 provided with a stop valve 10 and on which is stuck, upstream of the valve 10, a pipe 11 for filling with argon itself provided with a valve stop 12.
  • the cooler shown in Figures 2 and 3 is of revolution about an axis X-X, assumed to be vertical for the convenience of the description, and comprises an inner tubular core 13 and a double outer shell 14 exposed under vacuum and forming Dewar.
  • An upper head 15 in the form of an inverted cup closes the upper end of the core 13 and of the annular space 16 between the core 13 and the casing 14; the space 16 however communicates with the surrounding atmosphere through a series of holes 17 passing through the head 15.
  • the internal diameters of the core 13 of the envelope 14 are approximately 2.5 mm and 5 mm respectively.
  • a sheath 18 is partially threaded and fixed in the lower end of the core 13.
  • the inner wall of the envelope 14 carries at its lower end a bottom 22 on which is fixed in heat exchange contact an element 23 to be cooled, which can be for example an infrared detector and which is located in space Dewar vacuum. Above the bottom 22 is thus defined a cooling chamber 24 which constitutes the coldest part of the device.
  • a rod 25 is slidably mounted inside the core 13.
  • This rod carries at its lower end a shutter needle 26 and, at its upper end, an electromagnet plunger 27.
  • the needle 26 slides with narrow adjustment in the sheath 19, that is to say with a clearance which, taking into account the coefficients of expansion, is, on the diameter , of the order of a few microns for the cold operating temperature of the cooler.
  • a clearance which, taking into account the coefficients of expansion, is, on the diameter , of the order of a few microns for the cold operating temperature of the cooler.
  • the needle is made of 100 C 6 steel and the sheath is made of bronze-beryllium, there will be a clearance, on the diameter, of 5 to 6 microns at room temperature, which corresponds to a clearance, on the diameter , from 2 to 3 microns at a cold temperature of the order of 80 to 90 K.
  • the plunger 27 slides in the head 15. Around the latter is arranged an electromagnet winding 28, the terminals 29, 30 of which are adapted to be connected to the terminals of a direct current source (not shown).
  • a spring 31 is compressed axially between the bottom of the head 15 and the plunger 27.
  • the rod 25 is guided on the one hand by the needle 26, on the other hand by the plunger 27.
  • a stop 32 for the plunger 27 is provided at the outlet of the head 15.
  • the cooler At rest, the cooler is in the state shown in Figure 3: the electromagnet is not supplied with electric current, so that the spring 31 is relaxed and pushes down the rod 27 to a stop position where the needle 26 closes the orifice 21 to the nearest sliding clearance (5 to 6 microns on the diameter since the device is at room temperature).
  • the valve 10 of the pipe 9 is opened, so that the argon under high pressure is sent into the pipe 19 and is expanded at high flow rate (for example 1000 to 1500 Nl / h) as the orifice 21.
  • high flow rate for example 1000 to 1500 Nl / h
  • the expanded and consequently cooled argon rises between the turns of the pipe 19 until it is discharged into the surrounding atmosphere through the orifices 17, cooling the high pressure argon.
  • the temperature prevailing in the chamber 24 decreases more and more.
  • the pressure drops in chamber 3 of the tank.
  • the pressure of chamber 3 is sufficiently lower than that of chamber 4 (400 bars in this example) to cause the rupture of the foil 6.
  • the nitrogen contained in chamber 4 then flushes out Almost instantaneously from the reservoir, the remainder of argon, then flows at a high flow rate (for example 600 to 800 Nl / h) in line 19 to relax as the orifice 21 passes.
  • a high flow rate for example 600 to 800 Nl / h
  • the electrical supply to the winding 28 is cut, for example by means of a timer, so that the spring 31 instantly returns the rod 25 to its initial position in FIG. 3: the needle 26 closes the orifice 21 and, being pushed laterally by the gas jet leaving this orifice, is at a distance j from the latter equal to the diametral clearance at low temperature, ie 2 to 3 microns with the values numbers indicated above.
  • the flow rate is thus suddenly reduced to a low value, preferably at least ten times lower than its previous value; the pressure drop of the low pressure circuit, which was of the order of a few bars, is reduced by the same amount, which makes it possible to obtain, in chamber 24, liquid nitrogen at a temperature close to the boiling point of nitrogen at atmospheric pressure, i.e. around 80 K.
  • FIG. 4 shows the variation of the temperature in the chamber 24 as a function of time.
  • cooling results solely from the expansion of the argon at high flow rates. As this gas has a significant Joule-Thomson effect, this cooling is very rapid.
  • This time can be chosen to abruptly decrease the nitrogen flow (time t2).
  • the final curve C3 of FIG. 4 is then obtained, which is parallel to the curve C4 corresponding to the case where the entire cooling operation is carried out with nitrogen at low flow rate.
  • This curve C3 is very satisfactory if it is desired to reach a final temperature of between 85 and 90 K. But to descend lower in temperature, it is preferable to allow the nitrogen to flow at a high rate until an instant t3 , posterior to t2, where a certain amount of nitrogen under a few bars has formed in the chamber 24 (point D of FIG. 4). In this case, the reduction in the nitrogen flow causes a very rapid vaporization of part of this liquid (flash effect), the temperature of which drops almost instantaneously in the vicinity of 80 K. We then obtain the final curve C5 of Figure 4.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)

Abstract

1. A method of supplying a Joule-Thompson cooler comprising a high-pressure conduit (19) which terminates in an high-pressure orifice (21), and a low-pressure draining circuit (24-16-17) in a heat exchange relationship with the high-pressure conduit (19) and into which the expansion orifice (21) opens, this method being of the type in which the high-pressure conduit (19) is supplied successively with a priming fluid and then with a working fluid, characterised in that the change from the priming fluid to the working fluid occurs when the cooling rate provided by the first fluid falls below the cooling rate provided by the second fluid and in that the working fluid is initially used at a high rate of flow, after which its rate of flow is abruptly reduced to end the cooling stage of the cooler.

Description

La présente invention est relative à un procédé d'alimentation d'un refroidisseur Joule-Thomson comprenant une conduite haute pression qui se termine par un orifice de détente , et un circuit d'évacuation basse pression en relation d'échange thermique avec la conduite haute pression et dans lequel débouche l'orifice de détente, et plus particulièrement à un procédé du type dans lequel on alimente successivement la conduite haute pression avec un fluide de démarrage puis avec un fluide de travail.The present invention relates to a method for supplying a Joule-Thomson cooler comprising a high pressure line which ends in a pressure relief port, and a low pressure discharge circuit in heat exchange relation with the high line pressure and into which the expansion orifice opens, and more particularly to a method of the type in which the high pressure pipe is successively supplied with a starting fluid and then with a working fluid.

De façon générale, on cherche à réduire le temps de mise en froid ainsi que la température froide limite des refroidisseurs Joule-Thomson. La température limite que l'on peut atteindre est la température d'ébullition du fluide détendu, tandis que la vitesse de refroidissement dépend de l'effet Joule-Thomson de ce fluide, c'est-à-dire de la puissance frigorifique procurée par sa détente. Pour concilier ces deux objectifs, on a proposé des procédés du type précité (brevet FR 2322 337), mais, avec ces procédés connus, il n'a pas été possible d'obtenir en un temps très court des températures suffisamment basses pour certaines applications, par exemple une température d'environ 80 K avec comme fluide de démarrage et de travail, respectivement, l'argon et l'azote.In general, it is sought to reduce the cooling time as well as the limit cold temperature of the Joule-Thomson chillers. The limit temperature that can be reached is the boiling temperature of the expanded fluid, while the cooling rate depends on the Joule-Thomson effect of this fluid, i.e. the cooling power provided by his relaxation. To reconcile these two objectives, processes of the aforementioned type have been proposed (patent FR 2322 337), but, with these known processes, it has not been possible to obtain in a very short time temperatures sufficiently low for certain applications. , for example a temperature of approximately 80 K with, as starting and working fluid, respectively, argon and nitrogen.

L'invention a pour but de permettre d'obtenir en un temps très court des températures plus basses qu'il n'était possible jusqu'à présent.The object of the invention is to allow lower temperatures to be obtained in a very short time than has hitherto been possible.

A cet effet, l'invention a pour objet un procédé du type précité, caractérisé en ce qu'on utilise le fluide de travail d'abord à fort débit, puis on réduit brusquement son débit pour terminer la phase de mise en froid du refroidisseur.To this end, the subject of the invention is a process of the aforementioned type, characterized in that the working fluid is used first at a high flow rate, then its flow rate is suddenly reduced to finish the cooling phase of the cooler .

Suivant des caractéristiques préférées :
- on assure la réduction du débit en masquant l'orifice de détente par une surface laissant subsister à la périphérie de l'orifice un passage de fuite ;
- on réduit le débit du fluide de travail dans un rapport au moins égal à 10 ;
- on passe du fluide de démarrage au fluide de travail lorsque la vitesse du refroisissement assuré par le premier devient inférieure à la vitesse du refroidissement assuré par le second.According to preferred characteristics:
- the flow is reduced by masking the expansion orifice with a surface allowing a leakage passage to remain at the periphery of the orifice;
- the flow rate of the working fluid is reduced in a ratio at least equal to 10;
- We go from the starting fluid to the working fluid when the cooling speed provided by the first becomes lower than the cooling speed provided by the second.

L'invention a également pour objet un appareil de refroidissement destiné à mettre en oeuvre le procédé défini ci-dessus. Cet appareil, du type comprenant une première source de fluide de démarrage sous une première haute pression, une seconde source de fluide de travail sous une seconde haute pression, un refroidisseur Joule-Thomson comprenant une conduit haute pression qui se termine par un orifice de détente et un circuit d'évacuation basse pression en relation d'échange thermique avec la conduite haute pression et dans lequel débouche l'orifice de détente, et des moyens de commutation pour relier la conduite haute pression d'abord à la première source puis à la seconde source, est caractérisé en ce qu'il comprend des moyens d'étranglement pour réduire brusquement le débit s'écoulant dans la conduite haute pression.The invention also relates to a cooling device intended to implement the method defined above. This device, of the type comprising a first source of starting fluid under a first high pressure, a second source of working fluid under a second high pressure, a Joule-Thomson cooler comprising a high pressure conduit which ends in a pressure relief port and a low pressure discharge circuit in heat exchange relationship with the high pressure pipe and into which the expansion orifice opens, and switching means for connecting the high pressure pipe first to the first source and then to the second source, is characterized in that it comprises throttling means for abruptly reducing the flow rate flowing in the high pressure pipe.

Dans un mode de réalisation préféré, les moyens d'étranglement comprennent un obturateur mobile d'une première position où l'orifice de détente est libre à une seconde position où cet orifice est masqué par une surface laissant substituer à la périphérie de l'orifice un passage de fuite.In a preferred embodiment, the throttling means comprise a shutter movable from a first position where the expansion orifice is free to a second position where this orifice is masked by a surface allowing the periphery of the orifice to be substituted an escape route.

Un exemple de mise en oeuvre de l'invention va maintenant être décrit en regard des dessins annexés, sur lesquels :

  • - la figure 1 représente en coupe longitudinale un réservoir de gaz sous haute pression d'un appareil suivant l'invention ;
  • - la figure 2 est une vue en coupe longitudinale d'un refroidisseur Joule-Thomson associé au réservoir de la figure 1 ;
  • - la figure 3 est une vue analogue à la figure 2 qui montre le refroidisseur dans une autre phase de son fonctionnement ; et
  • - la figure 4 est un diagramme montrant l'évolution de la température du refroidisseur en fonction du temps lorsque le procédé suivant l'invention est mis en oeuvre.
An example of implementation of the invention will now be described with reference to the accompanying drawings, in which:
  • - Figure 1 shows in longitudinal section a gas tank under high pressure of an apparatus according to the invention;
  • - Figure 2 is a longitudinal sectional view of a Joule-Thomson cooler associated with the tank of Figure 1;
  • - Figure 3 is a view similar to Figure 2 which shows the cooler in another phase of its operation; and
  • - Figure 4 is a diagram showing the evolution of the temperature of the cooler as a function of time when the method according to the invention is implemented.

Le réservoir 1 représenté à la figure 1 est divisé en deux chambres inégales par une cloison transversale 2 : une chambre auxiliaire aval 3 contenant un fluide de démarrage à effet Joule-Thomson important mais relativement peu volatil, par exemple de l'argon, sous une première haute pression qui peut être de l'ordre de 700 bars, et une chambre principale amont 4 contenant un fluide de travail plus volatil et à effet Joule-Thomson moindre, par exemple de l'azote, sous une seconde haute pression au plus égale à la première haute pression, par exemple de l'ordre de 400 bars.The reservoir 1 shown in FIG. 1 is divided into two unequal chambers by a transverse partition 2: a downstream auxiliary chamber 3 containing a starting fluid with Joule-Thomson effect which is large but relatively not very volatile, for example argon, under a first high pressure which can be of the order of 700 bars, and an upstream main chamber 4 containing a more volatile working fluid and with a lesser Joule-Thomson effect, for example nitrogen, within one second high pressure at most equal to the first high pressure, for example of the order of 400 bars.

La cloison 2 est percée d'un orifice 5 masqué par un morceau de clinquant 6 appliqué sur la face avant de la cloison. Une conduite 7 de remplissage en azote, pourvue d'une vanne d'arrêt 8, débouche dans la chambre amont 4 du réservoir. De la chambre aval 3 part une conduite de sortie 9 pourvue d'une vanne d'arrêt 10 et sur laquelle se pique, en amont de la vanne 10, une conduite 11 de remplissage en argon elle-même pourvue d'une vanne d'arrêt 12.The partition 2 is pierced with an orifice 5 masked by a piece of foil 6 applied to the front face of the partition. A nitrogen filling pipe 7, provided with a shut-off valve 8, opens into the upstream chamber 4 of the tank. From the downstream chamber 3 leaves an outlet pipe 9 provided with a stop valve 10 and on which is stuck, upstream of the valve 10, a pipe 11 for filling with argon itself provided with a valve stop 12.

Le refroidisseur représenté aux figures 2 et 3 est de révolution autour d'un axe X-X, supposé vertical pour la commodité de la description, et comprend un noyau intérieur tubulaire 13 et une double enveloppe extérieure 14 insolée sous vide et formant Dewar. Une tête supérieure 15 en forme de coupelle inversée obture l'extrémité supérieure du noyau 13 et de l'espace annulaire 16 compris entre le noyau 13 et l'enveloppe 14 ; l'espace 16 communique toutefois avec l'atmosphère environnante par une série de trous 17 traversant la tête 15. Les diamètres intérieurs du noyau 13 de l'enveloppe 14 sont respectivement de 2,5 mm et de 5 mm environ.The cooler shown in Figures 2 and 3 is of revolution about an axis X-X, assumed to be vertical for the convenience of the description, and comprises an inner tubular core 13 and a double outer shell 14 exposed under vacuum and forming Dewar. An upper head 15 in the form of an inverted cup closes the upper end of the core 13 and of the annular space 16 between the core 13 and the casing 14; the space 16 however communicates with the surrounding atmosphere through a series of holes 17 passing through the head 15. The internal diameters of the core 13 of the envelope 14 are approximately 2.5 mm and 5 mm respectively.

Un fourreau 18 est partiellement enfilé et fixé dans l'extrémité inférieure du noyau 13. Une conduite haute pression 19, constituée d'un tube portant une ailette hélicoïdale, est bobinée en hélice sur toute la longueur du noyau 13, en contact avec celui-ci et avec la paroi intérieure de l'enveloppe 14 ; son extrémité supérieure traverse la tête 15 et est reliée à la conduite de sortie 9 du réservoir 1, et son extrémité inférieure 20 est fixée dans un perçage incliné vers le bas qui est prévu dans la paroi du fourreau 18 et dont la partie intérieure, de diamètre réduit, forme un orifice de détente 21.A sheath 18 is partially threaded and fixed in the lower end of the core 13. A high pressure pipe 19, consisting of a tube carrying a helical fin, is helically wound over the entire length of the core 13, in contact with it. ci and with the inner wall of the envelope 14; its upper end passes through the head 15 and is connected to the outlet pipe 9 from the tank 1, and its lower end 20 is fixed in a downwardly inclined bore which is provided in the wall of the sheath 18 and whose inner part, of reduced diameter, forms an expansion orifice 21.

La paroi intérieure de l'enveloppe 14 porte à son extrémité inférieure un fond 22 sur lequel se fixe en contact d'échange thermique un élément 23 à refroidir, qui peut être par exemple un détecteur infra-rouge et qui est situé dans l'espace sous vide du Dewar. Au-dessus du fond 22 est ainsi délimitée une chambre de refroidissement 24 qui constitue la partie la plus froide du dispositif.The inner wall of the envelope 14 carries at its lower end a bottom 22 on which is fixed in heat exchange contact an element 23 to be cooled, which can be for example an infrared detector and which is located in space Dewar vacuum. Above the bottom 22 is thus defined a cooling chamber 24 which constitutes the coldest part of the device.

Une tige 25 est montée coulissante à l'intérieur du noyau 13. Cette tige porte à son extrémité inférieure une aiguille obturatrice 26 et, à son extrémité supérieure, un plongeur d'électro-aimant 27. L'aiguille 26 coulisse à ajustement étroit dans le fourreau 19, c'est-à-dire avec un jeu qui, compte tenu des coefficients de dilatation, est, sur le diamètre, de l'ordre de quelques microns pour la température froide de fonctionnement du refroidisseur. Par exemple, si l'aiguille est en acier 100 C 6 et le fourreau en bronze-béryllium, on prévoira un jeu, sur le diamètre, de 5 à 6 microns à la température ambiante, ce qui correspond à un jeu, sur le diamètre, de 2 à 3 microns à une température froide de l'ordre de 80 à 90 K.A rod 25 is slidably mounted inside the core 13. This rod carries at its lower end a shutter needle 26 and, at its upper end, an electromagnet plunger 27. The needle 26 slides with narrow adjustment in the sheath 19, that is to say with a clearance which, taking into account the coefficients of expansion, is, on the diameter , of the order of a few microns for the cold operating temperature of the cooler. For example, if the needle is made of 100 C 6 steel and the sheath is made of bronze-beryllium, there will be a clearance, on the diameter, of 5 to 6 microns at room temperature, which corresponds to a clearance, on the diameter , from 2 to 3 microns at a cold temperature of the order of 80 to 90 K.

Le plongeur 27 coulisse dans la tête 15. Autour de celle-ci est disposé un bobinage d'électro-aimant 28 dont les bornes 29, 30 sont adaptées pour être reliées aux bornes d'une source de courant continu (non représentée). Un ressort 31 est comprimé axialement entre le fond de la tête 15 et le plongeur 27. Le guidage de la tige 25 est assuré d'une part par l'aiguille 26, d'autre part par le plongeur 27. Une butée 32 pour le plongeur 27 est prévue au débouché de la tête 15.The plunger 27 slides in the head 15. Around the latter is arranged an electromagnet winding 28, the terminals 29, 30 of which are adapted to be connected to the terminals of a direct current source (not shown). A spring 31 is compressed axially between the bottom of the head 15 and the plunger 27. The rod 25 is guided on the one hand by the needle 26, on the other hand by the plunger 27. A stop 32 for the plunger 27 is provided at the outlet of the head 15.

Au repos, le refroidisseur est dans l'état représenté à la figure 3 : l'électro-aimant n'est pas alimenté en courant électrique, de sorte que le ressort 31 est détendu et repousse vers le bas la tige 27 jusqu'à une position de butée où l'aiguille 26 obture l'orifice 21 au petit jeu de coulissement près (5 à 6 microns sur le diamètre puisque le dispositif est à température ambiante).At rest, the cooler is in the state shown in Figure 3: the electromagnet is not supplied with electric current, so that the spring 31 is relaxed and pushes down the rod 27 to a stop position where the needle 26 closes the orifice 21 to the nearest sliding clearance (5 to 6 microns on the diameter since the device is at room temperature).

Lors de la mise en froid, le bobinage 28 est mis sous tension et fait remonter le plongeur 27, la tige 25 et l'aiguille 26 à l'encontre du ressort 31 jusqu'à la position de la figure 2, où l'aiguille 26 dégage complètement l'orifice 21. Ce dernier peut alors être considéré comme débouchant librement dans la chambre 24.When cooling, the winding 28 is energized and raises the plunger 27, the rod 25 and the needle 26 against the spring 31 to the position of Figure 2, where the needle 26 completely clears the orifice 21. The latter can then be considered as freely opening into the chamber 24.

Dans cette position, on ouvre la vanne 10 de la conduite 9, de sorte que l'argon sous haute pression est envoyé dans la conduite 19 et est détendu à fort débit (par exemple 1000 à 1500 Nl/h) au passage de l'orifice 21. L'argon détendu et, par suite, refroidi remonte entre les spires de la conduite 19 jusqu'à être évacué dans l'atmosphère environnante par les orifices 17, en refroidissant l'argon haute pression. Ainsi, la température régnant dans la chambre 24 diminue de plus en plus.In this position, the valve 10 of the pipe 9 is opened, so that the argon under high pressure is sent into the pipe 19 and is expanded at high flow rate (for example 1000 to 1500 Nl / h) as the orifice 21. The expanded and consequently cooled argon rises between the turns of the pipe 19 until it is discharged into the surrounding atmosphere through the orifices 17, cooling the high pressure argon. Thus, the temperature prevailing in the chamber 24 decreases more and more.

Simultanément, la pression baisse dans la chambre 3 du réservoir. A un instant t1 qui sera précisé plus loin, la pression de la chambre 3 est suffisamment inférieure à celle de la chambre 4 (400 bars dans cet exemple) pour provoquer la rupture du clinquant 6. L'azote contenu dans la chambre 4 chasse alors quasi instantanément du réservoir le reliquat d'argon, puis s'écoule à fort débit (par exemple 600 à 800 Nl/h) dans la conduite 19 pour se détendre au passage de l'orifice 21.
Ainsi, la température continue a baisser dans la chambre 24, pour la même raison que précédemment.At the same time, the pressure drops in chamber 3 of the tank. At an instant t1 which will be specified below, the pressure of chamber 3 is sufficiently lower than that of chamber 4 (400 bars in this example) to cause the rupture of the foil 6. The nitrogen contained in chamber 4 then flushes out Almost instantaneously from the reservoir, the remainder of argon, then flows at a high flow rate (for example 600 to 800 Nl / h) in line 19 to relax as the orifice 21 passes.
Thus, the temperature continues to drop in chamber 24, for the same reason as above.

A un second instant t2 qui sera précisé plus loin, on coupe l'alimentation électrique du bobinage 28, par exemple au moyen d'un temporisateur, de sorte que le ressort 31 ramène instantanément la tige 25 à sa position initiale de la figure 3 : l'aiguille 26 obture l'orifice 21 et, étant repoussée latéralement par le jet de gaz sortant de cet orifice, se trouve à une distance j de celui-ci égale au jeu diamétral à basse température, soit 2 à 3 microns avec les valeurs numériques indiquées plus haut. Le débit est ainsi réduit brusquement à une valeur faible, de préférence au moins dix fois inférieure à sa valeur précédente ; la perte de charge du circuit basse pression, qui était de l'ordre de quelques bars, est réduite d'autant, ce qui permet d'obtenir dans la chambre 24 de l'azote liquide à une température voisine du point d'ébullition de l'azote à la pression atmosphérique, c'est-à-dire d'environ 80 K.At a second instant t2 which will be specified below, the electrical supply to the winding 28 is cut, for example by means of a timer, so that the spring 31 instantly returns the rod 25 to its initial position in FIG. 3: the needle 26 closes the orifice 21 and, being pushed laterally by the gas jet leaving this orifice, is at a distance j from the latter equal to the diametral clearance at low temperature, ie 2 to 3 microns with the values numbers indicated above. The flow rate is thus suddenly reduced to a low value, preferably at least ten times lower than its previous value; the pressure drop of the low pressure circuit, which was of the order of a few bars, is reduced by the same amount, which makes it possible to obtain, in chamber 24, liquid nitrogen at a temperature close to the boiling point of nitrogen at atmospheric pressure, i.e. around 80 K.

On a représenté à la figure 4 la variation de la température dans la chambre 24 en fonction du temps.FIG. 4 shows the variation of the temperature in the chamber 24 as a function of time.

Dans la première phase de la mise en froid, le refroidissement résulte uniquement de la détente de l'argon à fort débit. Comme ce gaz présente un effet Joule-Thomson important, ce refroidissement est très rapide.In the first phase of cooling, cooling results solely from the expansion of the argon at high flow rates. As this gas has a significant Joule-Thomson effect, this cooling is very rapid.

Cependant, il est limité d'une part par la volatilité relativement faible de l'argon, d'autre part par l'importante perte de charge, de l'ordre de quelques bars, créée par le fort débit dans le circuit basse pression, et c'est pourquoi la vitesse de descente en température diminue : si l'on poursuivait le refroidissement avec de l'argon à fort débit, on suivrait la courbe C1 de la figure 4. On choisit donc l'instant t1 au début du ralentissement du refroidissement provoqué par l'argon, comme illustré en A à la figure 4. A la température correspondante, en effet, l'azote à fort débit assure un refroidissement plus rapide que l'argon, comme le montre la courbe C2 de la figure 4, qui correspond à l'utilisation d'azote à fort débit pour assurer la totalité de la mise en froid. Comme on le comprend, c'est par le choix de la haute pression de l'argon et du volume de la chambre 3 que l'on peut déterminer l'instant t1 où le clinquant 6 se brisera.However, it is limited on the one hand by the relatively low volatility of argon, on the other hand by the significant pressure drop, of the order of a few bars, created by the high flow in the low pressure circuit, and this is why the speed of descent in temperature decreases: if one continued the cooling with argon at high flow, one would follow the curve C1 of figure 4. One thus chooses the moment t1 at the beginning of the deceleration of the cooling caused by argon, as illustrated in A in FIG. 4. At the corresponding temperature, in fact, the nitrogen at high flow rate ensures cooling faster than argon, as shown by curve C2 in FIG. 4, which corresponds to the use of nitrogen at high flow rate to ensure complete cooling. As we understand, it is by the choice of the high pressure of argon and the volume of the chamber 3 that we can determine the instant t1 when the foil 6 will break.

Ainsi, à partir de l'instant t1, la température décroît paral­lèlement à la courbe C2, c'est-à-dire moins vite qu'avant cet instant, puisque l'effet Joule-Thomson de l'azote est moins fort que celui de l'argon, mais plus rapidement que si l'on continue à utiliser de l'ar­gon. Puis, de nouveau, du fait de la proximité du point d'ébullition de l'azote et de la forte perte de charge du circuit basse pression, la vitesse de refroidissement décroît, à partir du point B de la figure 4.Thus, from time t1, the temperature decreases parallel to the curve C2, that is to say slower than before this time, since the Joule-Thomson effect of nitrogen is less strong than that argon, but faster than if you continue to use argon. Then, again, due to the proximity of the boiling point of nitrogen and the high pressure drop of the low pressure circuit, the cooling rate decreases, starting from point B in FIG. 4.

On peut choisir cet instant pour diminuer brusquement le débit d'azote (instant t2). On obtient alors la courbe finale C3 de la figure 4, qui est parallèle à la courbe C4 correspondant au cas où l'ensemble de la mise en froid serait effectuée avec de l'azote à faible débit.This time can be chosen to abruptly decrease the nitrogen flow (time t2). The final curve C3 of FIG. 4 is then obtained, which is parallel to the curve C4 corresponding to the case where the entire cooling operation is carried out with nitrogen at low flow rate.

Cette courbe C3 est très satisfaisante si l'on souhaite atteindre une température finale comprise entre 85 et 90 K. Mais pour descendre plus bas en température, il est préférable de laisser l'azote s'écouler à fort débit jusqu'à un instant t3, postérieur à t2, où certaine quantité d'azote sous quelques bars s'est formée dans la chambre 24 (point D de la figure 4). Dans ce cas, la réduction du débit d'azote provoque la vaporisation très rapide d'une partie de ce liquide (effet de flash), dont la température tombe quasi-instantanément au voisinage de 80 K. On obtient alors la courbe finale C5 de la figure 4.This curve C3 is very satisfactory if it is desired to reach a final temperature of between 85 and 90 K. But to descend lower in temperature, it is preferable to allow the nitrogen to flow at a high rate until an instant t3 , posterior to t2, where a certain amount of nitrogen under a few bars has formed in the chamber 24 (point D of FIG. 4). In this case, the reduction in the nitrogen flow causes a very rapid vaporization of part of this liquid (flash effect), the temperature of which drops almost instantaneously in the vicinity of 80 K. We then obtain the final curve C5 of Figure 4.

Avec les valeurs de pressions indiquées plus haut, on peut de cette manière atteindre en deux secondes environ une température de 80 K dans la chambre 24. De plus, grâce à l'utilisation d'un petit débit de fuite de travail, on peut conserver cette température pendant une longue période, de sorte que l'appareil possède une grande autonomie de fonctionnement.With the pressure values indicated above, it is possible in this way to reach a temperature of 80 K in chamber 24 in about two seconds. Furthermore, thanks to the use of a small working leak rate, it is possible to keep this temperature for a long time, so that the device has a long operating autonomy.

Claims (8)

1 - Procédé d'alimentation d'un refroidisseur Joule-Thomson comprenant une conduite haute pression (19) qui se termine par un orifice de détente (21), et un circuit d'évacuation basse pression (9,16,24) en relation d'échange thermique avec la conduite haute pression et dans lequel débouche l'orifice de détente, ce procédé étant du type dans lequel on alimente successivement la conduite haute pression (19) avec un fluide de démarrage puis avec un fluide de travail et étant caractérisé en ce qu'on utilise le fluide de travail d'abord à fort débit, puis on réduit brusquement son débit pour terminer la phase de mise en froid du refroidisseur.1 - Method for supplying a Joule-Thomson cooler comprising a high pressure line (19) which ends in an expansion orifice (21), and a low pressure discharge circuit (9,16,24) in relation heat exchange with the high pressure line and into which the expansion orifice opens, this method being of the type in which the high pressure line (19) is successively supplied with a starting fluid and then with a working fluid and being characterized in that the working fluid is used first at a high flow rate, then its flow rate is suddenly reduced to complete the cooling phase of the cooler. 2. Procédé suivant la revendication 1, caractérisé en ce qu'on assure la réduction du débit en masquant l'orifice de détente (21) par une surface (26) laissant subsister à la périphérie de l'orifice un passage de fuite.2. Method according to claim 1, characterized in that the reduction of the flow rate is ensured by masking the expansion orifice (21) by a surface (26) leaving a leakage passage at the periphery of the orifice. 3. Procédé suivant l'une des revendications 1 et 2, caractérisé en ce qu'on réduit le débit du fluide de travail dans un rapport au moins égal à 10.3. Method according to one of claims 1 and 2, characterized in that the flow rate of the working fluid is reduced in a ratio at least equal to 10. 4. Procédé suivant l'une quelconque des revendication 1 à 3, caractérisé en ce qu'on réduit le débit du fluide de travail lorsque la vitesse du refroidissement assuré par ce fluide commence à décroître.4. Method according to any one of claims 1 to 3, characterized in that the flow rate of the working fluid is reduced when the cooling speed provided by this fluid begins to decrease. 5. Procédé suivant l'une quelconque des revendications 1 à 3, caractérisé en ce qu'on maintient le fort débit du fluide de travail jusqu'à formation dans le circuit basse pression d'une certaine quantité de liquide, puis on procède à la réduction du débit de ce fluide.5. Method according to any one of claims 1 to 3, characterized in that the high flow rate of the working fluid is maintained until a certain amount of liquid is formed in the low pressure circuit, then the process is carried out. reduction in the flow of this fluid. 6. Procédé suivant l'une quelconque des revendications 1 à 5, caractérisé en ce qu'on passe du fluide de démarrage au fluide de travail lorsque la vitesse du refroidissement assuré par le premier devient inférieure à la vitesse du refroidissement assuré par le second.6. Method according to any one of claims 1 to 5, characterized in that one passes from the starting fluid to the working fluid when the speed of cooling provided by the first becomes lower than the speed of cooling provided by the second. 7. Appareil de refroidissement, du type comprenant une première source (3) de fluide de démarrage sous une première haute pression, une seconde source (4) de fluide de travail sous une seconde haute pression, un refroidisseur Joule-Thomson comprenant une conduite haute pression (19) qui se termine par un orifice de détente (21) et un circuit d'évacuation basse pression (9,16,24) en relation d'échange thermique avec la conduite haute pression et dans lequel débouche l'orifice de détente, et des moyens de commutation (6) pour relier la conduite haute pression (19) d'abord à la première source (3) puis à la seconde source (4), caractérisé en ce qu'il comprend des moyens d'étranglement (26) pour réduire brusquement le débit s'écoulant dans la conduite haute pression (19).7. Cooling device, of the type comprising a first source (3) of starting fluid under a first high pressure, a second source (4) of working fluid under a second high pressure, a Joule-Thomson cooler comprising a high pipe pressure (19) which ends with a pressure relief port (21) and a low pressure discharge circuit (9,16,24) in heat exchange relation with the high pressure line and into which the pressure relief port opens , and switching means (6) for connecting the upper pipe pressure (19) first at the first source (3) then at the second source (4), characterized in that it comprises throttling means (26) for abruptly reducing the flow rate flowing in the high pipe pressure (19). 8. Appareil suivant la revendication 7, caractérisé en ce que les moyens d'étranglement (26) comprennent un obturateur mobile d'une première position où l'orifice de détente (21) est libre à une seconde position où cet orifice est masqué par une surface laissant substituer à la périphérie de l'orifice un passage de fuite.8. Apparatus according to claim 7, characterized in that the throttling means (26) comprise a movable shutter from a first position where the expansion orifice (21) is free to a second position where this orifice is hidden by a surface allowing to replace the periphery of the orifice with a leakage passage.
EP19870401167 1986-05-26 1987-05-25 Feeding method for a joule-thomson cooler and cooling device for carrying it out Expired - Lifetime EP0247935B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8607449 1986-05-26
FR8607449A FR2599128A1 (en) 1986-05-26 1986-05-26 PROCESS FOR SUPPLYING A JOULE-THOMSON COOLER AND COOLING APPARATUS FOR ITS IMPLEMENTATION

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EP0247935A1 true EP0247935A1 (en) 1987-12-02
EP0247935B1 EP0247935B1 (en) 1990-04-25

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DE (1) DE3762452D1 (en)
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0945690A3 (en) * 1998-03-24 1999-11-24 Bodenseewerk Gerätetechnik GmbH Method and device for cooling of components, in particular of infrared detectors in seeker heads
US11001500B2 (en) 2015-06-25 2021-05-11 Irbis Technology LLC Method, apparatus and system for producing granulated solid carbon dioxide

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2991633A (en) * 1958-03-17 1961-07-11 Itt Joule-thomson effect cooling system
US3095711A (en) * 1962-01-31 1963-07-02 Jr Howard P Wurtz Double cryostat
US3320755A (en) * 1965-11-08 1967-05-23 Air Prod & Chem Cryogenic refrigeration system
US3413819A (en) * 1966-05-09 1968-12-03 Hughes Aircraft Co Flow rate control for a joule-thomson refrigerator
US3415078A (en) * 1967-07-31 1968-12-10 Gen Dynamics Corp Infrared detector cooler
FR2095319A1 (en) * 1970-06-17 1972-02-11 Hymatic Eng Co Ltd CRYOGENIC REFRIGERANTS
US3714796A (en) * 1970-07-30 1973-02-06 Air Prod & Chem Cryogenic refrigeration system with dual circuit heat exchanger
FR2176544A1 (en) * 1972-03-23 1973-11-02 Air Liquide
US3942010A (en) * 1966-05-09 1976-03-02 The United States Of America As Represented By The Secretary Of The Navy Joule-Thomson cryostat cooled infrared cell having a built-in thermostat sensing element
FR2322337A1 (en) * 1975-08-26 1977-03-25 Air Liquide REFRIGERANT SUPPLY DEVICE FOR AN OPEN CIRCUIT REFRIGERATOR, AND REFRIGERATION SYSTEM INCLUDING SUCH A DEVICE
FR2417733A1 (en) * 1978-02-17 1979-09-14 Deutsche Forsch Luft Raumfahrt HELIUM II VAPORIZATION DEVICE, USED IN PARTICULAR FOR CARRYING OBJECTS AT VERY LOW TEMPERATURES
EP0020111A2 (en) * 1979-05-23 1980-12-10 Air Products And Chemicals, Inc. Arrangement comprising a cryogenic refrigerator and an insulated enclosure, and an assembly including such an arrangement
GB2085139A (en) * 1980-10-10 1982-04-21 Hymatic Engineering The Co Ltd Cryogenic cooling apparatus
EP0084308A2 (en) * 1982-01-19 1983-07-27 Societe Anonyme De Telecommunications (S.A.T.) Regulating device for a Joule-Thomson effect cooling apparatus

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2638206A1 (en) * 1975-08-26 1977-03-10 Air Liquide Isenthalpic refrigeration expansion feed - has feed circuit carrying alternate fluids with varying cooling capacities

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2991633A (en) * 1958-03-17 1961-07-11 Itt Joule-thomson effect cooling system
US3095711A (en) * 1962-01-31 1963-07-02 Jr Howard P Wurtz Double cryostat
US3320755A (en) * 1965-11-08 1967-05-23 Air Prod & Chem Cryogenic refrigeration system
US3942010A (en) * 1966-05-09 1976-03-02 The United States Of America As Represented By The Secretary Of The Navy Joule-Thomson cryostat cooled infrared cell having a built-in thermostat sensing element
US3413819A (en) * 1966-05-09 1968-12-03 Hughes Aircraft Co Flow rate control for a joule-thomson refrigerator
US3415078A (en) * 1967-07-31 1968-12-10 Gen Dynamics Corp Infrared detector cooler
FR2095319A1 (en) * 1970-06-17 1972-02-11 Hymatic Eng Co Ltd CRYOGENIC REFRIGERANTS
US3714796A (en) * 1970-07-30 1973-02-06 Air Prod & Chem Cryogenic refrigeration system with dual circuit heat exchanger
FR2176544A1 (en) * 1972-03-23 1973-11-02 Air Liquide
FR2322337A1 (en) * 1975-08-26 1977-03-25 Air Liquide REFRIGERANT SUPPLY DEVICE FOR AN OPEN CIRCUIT REFRIGERATOR, AND REFRIGERATION SYSTEM INCLUDING SUCH A DEVICE
FR2417733A1 (en) * 1978-02-17 1979-09-14 Deutsche Forsch Luft Raumfahrt HELIUM II VAPORIZATION DEVICE, USED IN PARTICULAR FOR CARRYING OBJECTS AT VERY LOW TEMPERATURES
EP0020111A2 (en) * 1979-05-23 1980-12-10 Air Products And Chemicals, Inc. Arrangement comprising a cryogenic refrigerator and an insulated enclosure, and an assembly including such an arrangement
GB2085139A (en) * 1980-10-10 1982-04-21 Hymatic Engineering The Co Ltd Cryogenic cooling apparatus
EP0084308A2 (en) * 1982-01-19 1983-07-27 Societe Anonyme De Telecommunications (S.A.T.) Regulating device for a Joule-Thomson effect cooling apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0945690A3 (en) * 1998-03-24 1999-11-24 Bodenseewerk Gerätetechnik GmbH Method and device for cooling of components, in particular of infrared detectors in seeker heads
US11001500B2 (en) 2015-06-25 2021-05-11 Irbis Technology LLC Method, apparatus and system for producing granulated solid carbon dioxide

Also Published As

Publication number Publication date
EP0247935B1 (en) 1990-04-25
ES2015309B3 (en) 1990-08-16
FR2599128A1 (en) 1987-11-27
DE3762452D1 (en) 1990-05-31

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