DK149559B - THERMOSTAT CONTROLLED HEAT ROOM - Google Patents

THERMOSTAT CONTROLLED HEAT ROOM Download PDF

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Publication number
DK149559B
DK149559B DK192075A DK192075A DK149559B DK 149559 B DK149559 B DK 149559B DK 192075 A DK192075 A DK 192075A DK 192075 A DK192075 A DK 192075A DK 149559 B DK149559 B DK 149559B
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DK
Denmark
Prior art keywords
heating chamber
heat
chamber according
cavities
cavity
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DK192075A
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Danish (da)
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DK192075A (en
DK149559C (en
Inventor
Carlo Bassani
Claus-Adolf Busse
Julien Loens
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Euratom
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Publication of DK149559B publication Critical patent/DK149559B/en
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Publication of DK149559C publication Critical patent/DK149559C/en

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
    • F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
    • F28D15/06—Control arrangements therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B17/00—Furnaces of a kind not covered by any preceding group
    • F27B17/02—Furnaces of a kind not covered by any preceding group specially designed for laboratory use
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D21/00—Arrangements of monitoring devices; Arrangements of safety devices
    • F27D21/0014—Devices for monitoring temperature
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
    • G01K1/00—Details of thermometers not specially adapted for particular types of thermometer
    • G01K1/02—Means for indicating or recording specially adapted for thermometers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
    • G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
    • G01K11/02—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using evaporation or sublimation, e.g. by observing boiling

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Sustainable Development (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Clinical Laboratory Science (AREA)
  • Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
  • Resistance Heating (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Furnace Details (AREA)
  • Control Of Temperature (AREA)
  • Devices For Use In Laboratory Experiments (AREA)
  • General Induction Heating (AREA)

Description

U9559U9559

Opfindelsen angår et lukket varmekammer med termostatstyring og dannet af mindst to dobbeltvægge-de, i forlængelse af hinanden placerede og elektrisk opvarmede varmetransportrør med kapillarstrukturer i 5 væghulrummene.BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a closed thermostatically controlled heating chamber formed by at least two double-walled, electrically heated, heat-transported tubes with capillary structures in the wall cavities.

Når et varmekammer anvendes f.eks. som labora-torieovn, er det vigtigt, at temperaturen og temperaturfordelingen i kammeret er nøjagtigt indstillelige. I specielle tilfælde ønskes så vidt muligt 10 isotermisk temperaturfordeling over en stor del af kammerets indre. En sådan temperaturfordeling kan opnås i varmetransportrør, hvis anvendelse som ovne er beskrevet i tysk patentskrift nr. 2 110 685 og fransk offentliggørelsesskrift nr 2 183 120.When a heating chamber is used e.g. As a laboratory oven, it is important that the temperature and temperature distribution in the chamber are precisely adjustable. In special cases, as far as possible, 10 isothermal temperature distribution is desired over a large part of the interior of the chamber. Such a temperature distribution can be obtained in heat transfer tubes, the use of which as stoves is described in German Patent Specification No. 2 110 685 and French Patent Publication No. 2 183 120.

15 Tysk patentskrift nr. 2 110 685 beskriver et cylindrisk, dobbeltvægget varmetransportrør med kapillarstruktur, som er åbent i den ene eller begge ender og anbragt i en elektrisk opvarmet ekstra ovn, som holder varmetransportrøret på den ønskede temperatur.German Patent No. 2,110,685 discloses a cylindrical, double-walled heat transfer tube with capillary structure which is open at one or both ends and arranged in an electrically heated auxiliary furnace which maintains the heat transport tube at the desired temperature.

20 Temperaturen styres ved hjælp af varmeeffekten.20 The temperature is controlled by the heat effect.

Det franske offentliggørelsesskrift 2 183 120 beskriver et varmekammer, som opvarmes ved hjælp af parallelle kanaler, som med henblik på temperaturreguleringen er sluttet til et fælles gastrykstyresystem, 25 og som er åbne i mindst den ene ende.French Patent Specification 2,183,120 discloses a heating chamber which is heated by means of parallel ducts connected to a common gas pressure control system for the purpose of temperature control, which are open at least one end.

Et varmekammer ifølge nærværende opfindelse er ejendommelig ved, at temperaturen i hvert væghulrum er individuelt indstillelig ved hjælp af et separat, til hulrummet sluttet gastrykstyresystem, og at varmeef-30 fekttætheden er indstillelig til forskellige værdier i hulrummenes længderetning.A heating chamber according to the present invention is characterized in that the temperature in each wall cavity is individually adjustable by means of a separate gas pressure control system connected to the cavity and that the heat density is adjustable to different values in the longitudinal direction of the cavities.

Eksperimenter har vist, at der ved konstant varmetilførsel med tilnærmelse gælder følgende relation mellem temperaturen T og trykket P: 2 149559 ΔΤ = ο 1 ΔΡ Τ ' ΡExperiments have shown that for constant heat supply with approximation, the following relation between temperature T and pressure P applies: 2 149559 ΔΤ = ο 1 ΔΡ Τ 'Ρ

Dette betyder, at det ønskede temperaturforløb kan indstilles hurtigt, præcist og meget stabilt.This means that the desired temperature range can be set quickly, accurately and very stable.

Sammenhængen mellem temperaturen og trykket 5 afhænger af damptrykkurven for arbejdsmediet. Da absolutte tryk let kan måles, er temperaturerne i kammeret absolut reproducerbare.The relationship between temperature and pressure 5 depends on the vapor pressure curve of the working medium. Since absolute pressures can be easily measured, the temperatures in the chamber are absolutely reproducible.

Ved målinger af det absolutte tryk under anvendelse af kommercielt udstyr var den relative fejl 10 ^ af størrelsesordenen 10 ^. Den tilsvarende tempera- K AJ -5 turfejl -ψ var derfor af.størrelsesordenen 10For absolute pressure measurements using commercial equipment, the relative error was 10 ^ of the order of 10 ^. The corresponding tempera- K AJ -5 trip error -ψ was therefore of the order of 10

Varmeeffekttæthedens lokale 'indstillelighed i kammerets længderetning gør det muligt at forebygge uregelmæssigheder i temperaturfordelingen hidrørende 15 fra konstruktionsmæssige eller driftsmæssige årsager.The local power density adjustability of the chamber in the longitudinal direction of the chamber makes it possible to prevent irregularities in the temperature distribution due to structural or operational reasons.

Den eksperimentelle bestemmelse af temperaturen i et varmetransportrør svarende til forskellige damptryk af et arbejdsmedium er beskrevet i tysk offentliggørelsesskrift nr. 1 473 739. Her anvendes et 20 varmetransportrør som damptrykmåler og kalorimeter ved høje temperaturer, idet man udnytter forskydningen af grænsefladen mellem arbejdsmediets gasfase og styregassen.The experimental determination of the temperature of a heat transfer tube corresponding to different vapor pressures of a working medium is described in German Publication No. 1,473,739. .

Opfindelsen forklares nærmere i det følgende 25 under henvisning til tegningen, hvor fig. 1 viser et længdesnit gennem en første udførelsesform for opfindelsen, og fig. 2 et skematisk længdesnit gennem en anden udførelsesform med flere varmekamre.The invention will be further explained in the following with reference to the drawing, in which: FIG. 1 is a longitudinal section through a first embodiment of the invention; and FIG. 2 is a schematic longitudinal section through another embodiment with several heating chambers.

30 I fig. 1 er vist et varmekammer 1 omgivet af to varmetransportrør 2 og 3 med væghulrum 2a og 3a. Elektriske varmelegemer er angivet med 4a, 4b, 5a og 5b. Temperaturen i hvert hulrum 2a og 3a regule- 3 149559 res ved styring af trykket i en styregas, der ledes ind i det pågældende hulrum fra et tilsluttet gastrykstyresystem 6. Endvidere kan varmeafgivelsen fra varmelegemerne 4a, 4b, 5a og 5b reguleres individu-5 elt.In FIG. 1, a heating chamber 1 is shown surrounded by two heat transport pipes 2 and 3 with wall cavities 2a and 3a. Electric heaters are indicated by 4a, 4b, 5a and 5b. The temperature in each cavity 2a and 3a is controlled by controlling the pressure in a control gas which is fed into the respective cavity from a connected gas pressure control system 6. Furthermore, the heat output from the heaters 4a, 4b, 5a and 5b can be individually controlled. .

Varmetransportrøret 2 er en i den ene ende lukket, dobbeltvægget cylinder, som består af en bægerformet del 2c og en indsats 2d, og varmetransportrøret 3 er et hult dæksel for røret 2's åbne 10 ende. Dækslet 3 og delen 2c holder og centrerer indsatsen 2d ved hjælp af afstandsorganer 7.The heat transfer tube 2 is a double-ended, closed-walled cylinder at one end, which consists of a cup-shaped part 2c and an insert 2d, and the heat transport tube 3 is a hollow cover for the open end of the tube 2. The cover 3 and the portion 2c hold and center the insert 2d by spacers 7.

Flanger på dækslet 3 og indsatsen 2d er forbundet gastæt ved hjælp af bolte 8. I et udførelseseksempel havde kammeret 1 en diameter på 20 cm og en anvende-15 lig længde på 50 cm. Hvis arbejdsmediet og konstruktionsmaterialerne er udvalgt på passende måde, kan kammeret dække et temperaturområde på op til 2000°C. I det viste eksempel i fig. 1 var væggene fremstillet af rustfrit stål, og arbejdsmediet var vand.Flanges on cover 3 and insert 2d are connected gas tightly by bolts 8. In one embodiment, chamber 1 had a diameter of 20 cm and a usable length of 50 cm. If the working medium and construction materials are appropriately selected, the chamber can cover a temperature range of up to 2000 ° C. In the example shown in FIG. 1, the walls were made of stainless steel and the working medium was water.

20 På oversiden af kammeret 1 er hulrummene 2a og 3a sluttet til hver sin af to kondensationskupler 9 og 10, som indeholder kølespiraler 9a og 10a, der gennemstrømmes af et kølemedium (f.eks. vand) i den med pile viste retning. I kondensationskuplerne udmun-25 der styregasledninger 11 og 12, som fører til de to styregassystemer 6.On the upper side of the chamber 1, the cavities 2a and 3a are connected to each of two condensation cups 9 and 10, which contain cooling coils 9a and 10a, which are flowed through a cooling medium (eg water) in the direction indicated by arrows. In the condensation domes, control gas lines 11 and 12 lead to the two control gas systems 6.

Kondensationskuplerne 9 og 10 virker som variable termiske modstande, hvori der dannes grænseflader eller -lag mellem dampen og styregassen, f.eks.The condensation domes 9 and 10 act as variable thermal resistors in which interfaces or layers are formed between the steam and the control gas, e.g.

30 argon. Returstrømningen af kondensat til varmekammeret fremmes ved hjælp af kapillarstrukturer 13, der består af flere lag af finmasket trådnet, som dækker hele U9559 4 indersiden af væghulrummene 2a og 3a. Lagene er indbyrdes forbundet ved hjælp af en bro 19, idet vindingsenderne i indsatsen 2d’s lag er bøjet radialt på en sådan måde, at de kommer i berøring med 5 bægerdelen 2c's lag. Herved forkortes kondensatets tilbagestrømningsbane.30 argon. The return flow of condensate to the heating chamber is promoted by capillary structures 13 consisting of several layers of fine mesh wire mesh covering the entire interior of the wall cavities 2a and 3a. The layers are interconnected by means of a bridge 19, the winding ends of the insert 2d's layers being radially bent in such a way that they come into contact with the layers of the cup 2c. This shortens the condensate backflow path.

Gastrykstyresystemerne 6 omfatter de førnævnte styregasledninger 11 og 12, trykmålere 11a og 12a, to par fint indstillelige nåleventiler 11b, 11c 10 og 12b, 12c, bufferlagre 14a og 14b, et gastil- førselslager 15 og de nødvendige forbindelsesledninger..! det omtalte eksempel var styregassens arbejds-temperatur maksimalt 250°C. Ændringer i styregastrykket resulterer i en forskydning af gas/væskefasegræn-15 sen i kondensationskuplen, hvorved den ønskede temperaturændring frembringes.The gas pressure control systems 6 comprise the aforementioned control gas lines 11 and 12, pressure gauges 11a and 12a, two pairs of finely adjustable needle valves 11b, 11c 10 and 12b, 12c, buffer bearings 14a and 14b, a gas supply bearing 15 and the necessary connection lines. In the example described, the operating temperature of the control gas was a maximum of 250 ° C. Changes in the control gas pressure result in a shift of the gas / liquid phase boundary in the condensation dome, thereby producing the desired temperature change.

Placeringen af varmelegemerne 4a, 4b, 5a og 5b og indstilleligheden af deres varmeafgivelse er valgt således, at kapillarstrukturerne 13 under normal 20 funktion ikke kan tørre ud og derved frembringe overhedet damp. Varmelegemerne er anbragt i den.neder-ste del af varmekammeret og er af opvarmning s tekniske grunde lagt delvis på indersiden og delvis på ydersiden af væghulrummene under kapillarstrukturen.The location of the heaters 4a, 4b, 5a and 5b and the adjustability of their heat release is chosen such that the capillary structures 13 during normal operation cannot dry out and thereby produce superheated steam. The heaters are located in the lower part of the heating chamber and, for heating reasons, are laid partly on the inside and partly on the outside of the wall cavities under the capillary structure.

25 Varmelegemerne er fremstillet af kommercielle25 The heaters are made of commercial

Thermocoax-kabler og er ført ud af kammeret gennem indsvejste rørstykker 16. Metalkappedelen er loddet eller svejst til det tilhørende rørstykke.Thermocoax cables and are passed out of the chamber through welded pipe pieces 16. The metal cap part is soldered or welded to the associated pipe piece.

Varmekammeret 1 er som helhed omgivet af et 30 termisk' isolerende lag 17 af mineraluld.The heating chamber 1 as a whole is surrounded by a thermally insulating layer 17 of mineral wool.

Det hule dæksel 3 har aflukkelige gennemføringer 18, men disse påvirker ikke ensartetheden af temperaturen i varmekammeret. De anvendes f.eks. for måling og tilførsel.The hollow cover 3 has closable holes 18, but these do not affect the uniformity of the temperature in the heating chamber. They are used e.g. for measurement and supply.

35 I udførelseseksemplet ifølge fig. 2 er varme kammeret sammensat af tre indbyrdes forbundne, dob-35 In the embodiment of FIG. 2, the heat chamber is composed of three interconnected,

Claims (5)

149559 beltvæggede varmetransportrør 19, 20 og 21, der er åbne i begge ender, og to i den ene ende lukkede varmetransportrør 22 og 23. De øvrige henvisningsbetegnelser angår dele, som funktionsmæssigt svarer til 5 dele i fig. 1 med samme benævnelser. En temperaturgradient langs væghulrummene, som er adskilt ved hjælp af skillevægge, kan reguleres ved indstilling af det tilsvarende styregastryk i hvert hulrum. 10 PATENTKRAV149559 belt-walled heat transfer tubes 19, 20 and 21 open at both ends and two heat-transport tubes closed at one end at one end. The other reference numerals refer to parts which functionally correspond to 5 parts in FIG. 1 with the same designations. A temperature gradient along the wall cavities separated by partitions can be controlled by adjusting the corresponding guide gas pressure in each cavity. 10 PATENT REQUIREMENTS 1. Lukket varmekammer (1) med termostatstyring og dannet af mindst to dobbeltvæggede, i forlængelse af hinanden placerede og elektrisk opvarmede varmetransportrør (2, 3) med kapillarstrukturer (13) i 15 væghulrummene (2a, 3a), kendetegnet ved, at temperaturen i hvert væghulrum (2a, 3a) er individuelt indstillelig ved hjælp af et separat, til hulrummet sluttet gastrykstyresystem (6), og at varmeeffekttæt-heden er indstillelig til forskellige værdier i 20 hulrummenes længderetning.1. Closed heating chamber (1) with thermostat control and formed by at least two double-walled, electrically heated and electrically heated heat transfer tubes (2, 3) with capillary structures (13) in the wall cavities (2a, 3a), characterized in that the temperature of each wall cavity (2a, 3a) is individually adjustable by a separate gas pressure control system (6) connected to the cavity and the heat power density is adjustable to different values in the longitudinal direction of the cavities. 2. Varmekammer ifølge krav 1,. kendetegne t ved, at væghulrummene (2a, 3a) er sluttet til de respektive gastrykstyresystemer (6) gennem kondensationskupler (10, 9) på varmekammerets overside.Heating chamber according to claim 1,. characterized in that the wall cavities (2a, 3a) are connected to the respective gas pressure control systems (6) through condensation domes (10, 9) on the upper side of the heating chamber. 3. Varmekammer ifølge krav 1 eller 2, k e n- d'etegnet ved, at de to varmetransportrør er udformet henholdsvis som en i den ene ende lukket hulcylinder (2) og som et hult dæksel (3).3. A heating chamber according to claim 1 or 2, characterized in that the two heat transport pipes are respectively formed as a hollow cylinder (2) at one end and as a hollow cover (3). 4. Varmekammer ifølge krav 2, kend. e te g- 30 net ved, at de elektriske varmelegemer (4a, 4b, 5a, 5b) er indbygget i væghulrummene (2a, 3a) modsat kondensationskuplerne (10, 9).Heating chamber according to claim 2, known. e, the electric heating elements (4a, 4b, 5a, 5b) are built into the wall cavities (2a, 3a) opposite the condensation cups (10, 9). 5. Varmekammer ifølge krav 4, kendetegnet ved, at varmelegemerne (4a, 4b, 5a, 5b) liggerHeating chamber according to claim 4, characterized in that the heating elements (4a, 4b, 5a, 5b) lie
DK192075A 1974-06-26 1975-05-02 THERMOSTAT CONTROLLED HEAT ROOM DK149559C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
LU70419 1974-06-26
LU70419A LU70419A1 (en) 1974-06-26 1974-06-26

Publications (3)

Publication Number Publication Date
DK192075A DK192075A (en) 1975-12-27
DK149559B true DK149559B (en) 1986-07-21
DK149559C DK149559C (en) 1987-03-30

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DK192075A DK149559C (en) 1974-06-26 1975-05-02 THERMOSTAT CONTROLLED HEAT ROOM

Country Status (11)

Country Link
JP (1) JPS5222145A (en)
BE (1) BE826621A (en)
CH (1) CH585498A5 (en)
DE (1) DE2516434C2 (en)
DK (1) DK149559C (en)
FR (1) FR2276546A1 (en)
GB (1) GB1510673A (en)
IE (1) IE40863B1 (en)
IT (1) IT1032445B (en)
LU (1) LU70419A1 (en)
NL (1) NL7505311A (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4067237A (en) * 1976-08-10 1978-01-10 Westinghouse Electric Corporation Novel heat pipe combination
DE3307454C2 (en) * 1983-03-03 1986-01-23 W.C. Heraeus Gmbh, 6450 Hanau Thick-film paste stoving oven
JPS6278256A (en) * 1985-09-25 1987-04-10 株式会社　羽島 Cloth cutter

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Publication number Publication date
DK192075A (en) 1975-12-27
JPS5222145A (en) 1977-02-19
LU70419A1 (en) 1974-10-17
CH585498A5 (en) 1977-02-28
IE40863L (en) 1975-12-26
GB1510673A (en) 1978-05-10
BE826621A (en) 1975-06-30
FR2276546A1 (en) 1976-01-23
FR2276546B1 (en) 1978-10-27
DE2516434C2 (en) 1982-12-30
DE2516434A1 (en) 1976-01-15
NL7505311A (en) 1975-12-30
IE40863B1 (en) 1979-08-29
JPS5735397B2 (en) 1982-07-28
IT1032445B (en) 1979-05-30
DK149559C (en) 1987-03-30

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