US3367415A - Anisotherm evaporation heattransfer structure - Google Patents

Anisotherm evaporation heattransfer structure Download PDF

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US3367415A
US3367415A US512090A US51209065A US3367415A US 3367415 A US3367415 A US 3367415A US 512090 A US512090 A US 512090A US 51209065 A US51209065 A US 51209065A US 3367415 A US3367415 A US 3367415A
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heat
protuberances
temperature
protuberance
curve
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Charles A E Beurtheret
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Compagnie Francaise Thomson Houston SA
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Compagnie Francaise Thomson Houston SA
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    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/02—Fuel elements
    • G21C3/04—Constructional details
    • G21C3/06—Casings; Jackets
    • G21C3/08—Casings; Jackets provided with external means to promote heat-transfer, e.g. fins, baffles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D1/00—Evaporating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/10—Water tubes; Accessories therefor
    • F22B37/101—Tubes having fins or ribs
    • 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
    • F25B39/00—Evaporators; Condensers
    • F25B39/02—Evaporators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F28F1/24—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
    • F28F1/26—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means being integral with the element
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
    • F28F13/18—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by applying coatings, e.g. radiation-absorbing, radiation-reflecting; by surface treatment, e.g. polishing
    • F28F13/185—Heat-exchange surfaces provided with microstructures or with porous coatings
    • F28F13/187—Heat-exchange surfaces provided with microstructures or with porous coatings especially adapted for evaporator surfaces or condenser surfaces, e.g. with nucleation sites
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

Definitions

  • This invention relates to heat transfer structures of the type including a wall having one side exposed to a source of heat and its other side in contact with a vaporizable liquid into which the heat is dissipated. More especially, the invention relates to such structures that operate in a non-isotherm (or anisotherm) manner, as this term will be presently defined.
  • Anisotherm evaporation heatdissipating structures are now widely used in many fields of engineering, including high-power electron tubes, evaporators, and other apparatus.
  • the graph 1 is well-known as the Nukiyama curve, and seeks to express the law of heat transfer between a wall made of heat conductive material and a boiling liquid (water at atmospheric pressure in the case of the graph shown).
  • the ordinates represent the rate of heat transfer per unit area (otherwise stated heat flux density) in watts per square centimeter, and the abscissae represent surface temperatures in C. above saturation temperature t (100 C. in this instance).
  • the curve has four main sections: a lowslope section A up to a knee point N, over which heat transfer is through normal convection, without the liquid boiling; a second steep-rising section B, from knee N to peak M, in which the water undergoes normal or socalled nucleate boiling, and the rate of heat transfer through convection is greatly increased; a third drooping section C from peak M to point L (known as the Leidenfrost point), which corresponds to a region of transition; and a fourth rising final section D from point L onwards, in which the vaporization of the water proceeds by socalled film-boiling (or spheroidal state) rather than the ordinary nucleate or bubble-boiling as at low surface temperatures.
  • a lowslope section A up to a knee point N over which heat transfer is through normal convection, without the liquid boiling
  • a second steep-rising section B from knee N to peak M, in which the water undergoes normal or socalled nucleate boiling, and the rate
  • the meaning of the graph is that, when any surface element is held at any strictly constant temperature selected on the abscissae axis, as by appropriately regulating the heat applied from the heat source to the wall, then the rate of heat dissipation remains generally constant Patented Feb. 6, 1968 at the corresponding ordinate value of the curve.
  • the heat source usually imposes the heat flux density through the wall and under these conditions it is found that the operating point first follows the first two rising sections A and B of the curve as far as the peak point M, and then, the operating point jumps from point M to a point Q positioned at a corresponding ordinate on the fourth section D, resulting in an increase in surface temperature as from about C. to more than 1000 C.
  • a continuous temperature gradient was thus deliberately created along the side surfaces of the protuberances.
  • This continuous gradient encompassed the critical temperature from a temperature well below to a temperature well above it, over a wide range that extended continuously from cooler areas in which ordinary nucleate ebullition or bubble boiling prevails (arc B of the Nukiyama curve) through hot areas within the transitional region (arc C) and, if so desired, on to the initial part of the very hot areas in the film boiling region (are D).
  • the temperature gradient was found to be effective in stabilizing the peak point M, and the ensuing transitional region ML, earlier reputed unstable.
  • the operating point of the heat transfer process then smoothly followed a descending arc of the curve instead of tending to jump uncontrollably to the intolerably high temperatures of more than 1000 C. (such as represented by point Q) so soon as the temperature would anywhere locally approach the critical temperature of point M, as was the case in the older types of evaporationcooling structures based on the isotherm approach.
  • Non-isotherm cooling structures constructed in accordance with the above principles are now widely used for the cooling of the anodes in electronic transmitter tubes, and have virtually replaced all earlier types of cooling instrumentalities as regards transmitter tubes of the higher power ratings. Similar structures are now being applied on an experimental scale to the cooling of combustion engine cylinders and in other fields.
  • FIG. 1 is a graph, previously referred to, showing both the standard Nukiyama curve and the partly modified curve established by the applicant for the transitional region under non-isotherm conditions when a high value of temperature gradient is involved;
  • FIGS. 2, 3 and 4 are enlarged sectional views of respective embodiments of the invention using different shape protuberances
  • FIG. 5 is a stylized representation showing the pattern of liquid and vapor that tends to form adjacent the nonisotherm cooling structure of the present invention under operating conditions approaching maximum or nominal heat dissipation rate;
  • FIG. 5a is a similar representation of the vaporization attcrn resent in the narrow-channel structure of a P P 4 plicants earlier U.S. Patent No. 3,235,004 (Ser. No. 260,245).
  • FIG. 6 is a view in projection on a plane at right angles to that of FIGS. 2, 3 and 4, as indicated by the arrows VIVI in FIG. 3, but to a somewhat smaller scale, and illustrating a modification of the invention:
  • FIGS. 7 and 8 are views similar to FIGS. 2, 3 and 4 showing further modifications in the shape of the protuberances, usable according to the present invention.
  • the new curve MRL would represent an example of the over-all, complex vaporization conditions that are actually present in the case of a non-isotherm system
  • the curve MUL which alone was recognized by earlier Workers, is a fictional curve that only can represent a series of flux measurements successively performed on an isotherm surface at a series of different temperatures, but has no true physical significance to the extent that the full set of its points considered simultaneously can at no time coexist in any real non-isothermal system unless the gradient of temperature along the surface is very low.
  • the total vaporization curve of the form MRL can elfectively and reliably be established in an anisotherm heat-dissipating structure without necessitating narrow grooves between the protuberances, provided each protuberance is so proportioned that, when the structure is operated at or near maximum nominal heatinput conditions, each protuberance is individually capable of supporting the requisite temperature drop along its sidewalls as generated by said nominal heat input, and is also capable of conducting all of said heat applied to its base, into the surrounding fluid.
  • FIG. 5 shows the vaporization pattern present in the structure of the invention under maximum heat input conditions.
  • Each protuberance here shown triangular in contour
  • This ever-present vapor jet continually breaks up the edge of the film vapor that would otherwise tend to seal off the area of transitional (semi-film) boiling from the adjacent area of nucleate boiling, on each side surface of the protuberance.
  • FIG. 5a (essentially similar to FIG. 4 of the aboveidentified prior patent) shows the vaporization pattern of the narrow-groove structure under similar operating conditions. As described in detail in the prior patent, jets of vapor are ejected from the outer ends of the individual grooves.
  • each side surface is wetted with liquid substantially throughout its length.
  • FIG. 5a the opposite side surfaces of each narrow groove cooperate to create this turbulance
  • FIG. 5 it is the opposite surfaces of each protuberance which cooperate in creating the desired turbulence and thus achieve an equivalent result without having to rely on the provision of the undesirably narrow grooves between the protuberances.
  • PEG. 2 of the drawings shows one form of heat dissipating structure with which the invention may be embodied.
  • the structure generally designated 3 includes a generally flat metallic wall 5 having protuberances or bosses 4 integrally projecting from one of its sides. It will be understood that in operation, this embossed side of the structure, hereinafter termed the outer side, is immersed in a boiling liquid, e.g. water, and that heat to be dissipated is applied to the opposite, or inner side of the wall 5 the shape of which is not critical.
  • a boiling liquid e.g. water
  • the protuberances 4 may be disposed in rows aligned along two mutually perpendicular directions of the structure, with similar contours and spacings as seen in both directions; or they may constitute elongated parallel ribs.
  • the protuberances 4 may assume various sectional contours, some of which are later described, it is important that they be tapered over at least part of their length in order to promote the afore-mentioned ejection of vapor from the tips of the protuberances.
  • the protuberances have a compositely tapered, obelisk-like shape including a frusto-pyramidal base section of large taper angle, a longer frusto-pyramidal body part of smaller taper angle and an outer tip or apex in the form of a pyradim of large taper angle.
  • the bases of the protuberances are substantially contiguous.
  • Each protuberance is long enough to allow the input heat flux applied to its base to generate the requisite temperature drop between the base and apex of the protuberance;
  • 0 b is a
  • c is the conductivity factor of the material
  • k is a safety factor, equal to or somewhat greater than unity (but not exceeding 2).
  • the temperature drop in operation is selected in dependency on the nature of the material, the nature of the evaporating fluid and the pressure conditions. 0 should not be taken substantially less than the extent of the transitional range t t (see FIG. 1), in order to ensure that a sufliciently broad temperature gradient, a prerequisite for the proper operation of the non-isotherm evaporation-cooling system, is present. On the other hand, 0 cannot be taken substantially greater than (t t since otherwise the maximum temperature t in the metal at the base of the protuberances might rise to unnecessary heights. In the case where the liquid is water at atmospheric pressure, the two bounding values just indicated for 0 are C. and C. respectively, as will be evident from FIG. 1.
  • the temperature drop 0 is taken as small as 50 C. (with water at ordinary atmospheric pressure). Where the evaporating liquid is pressurized, and/Or is other than water, the temperature drop 0 may take values outside the just-indicated range of 80-125 C., as will be later indicated.
  • the second condition is derived from a consideration of the Laplace law of flux conservation through the protuberance.
  • the total amount of heat entering the base 9 of the protuberance must equal the total amount of heat issuing from the outer lateral surfaces of the protuberance, arrow 8, into the surrounding boiling liquid, per unit time.
  • the total amount of heat entering the base of the protuberance is s where s is the area of the base 9.
  • the total amount of heat leaving the outer side surfaces of the protuberance is s t where s is the total area of the side surfaces of the protuberance, and (p is the outgoing heat flux density, or mean rate of heat outflow referred to unit area of the protuberance side surfaces.
  • ga will be more fully defined presently.
  • the second condition must state that the side surface area s is large enough to provide for a complete outflow of heat at the rate (p therethrough in the presence of heat at the specified, nominalf rate through the base surface area s of the protuberance.
  • the outgoing heat flux value (p appears in the graph of FIG. 1 as the mean value of flux density averaged over the temperature range t t of interest, under the modi- 2 -a a (curve MRI.)
  • Equations I and II can be expressed in units selected among any coherent system of measures and weights, whatever are the bases of the units.
  • Equations I and II would, under ideal conditions, be taken with the coeflicient k equal to unity. That k is generally taken greater than 1 merely expresses a safety consideration, to allow for such uncertain contingencies as imperfect surface of the structure, possible occurrence of overloads in use, and the like. Making k greater than 1 means that the protuberances are built somewhat larger than would be strictly necessary under ideal conditions, thereby improving operating safety (but not efficiency).
  • An upper limit for the safety factor k is set essentially by structural and economical considerations, and it is found in practice that such upper limit can conveniently be taken as two.
  • FIG. 3 A simple and advantageous embodiment of the invention is shown in FIG. 3, where the protuberances have a triangular contour in section, with adjoining bases.
  • the protuberances may be square-base pyramids disposed in rows aligned along two e.g. orthogonal directions of the wall surface, or they may be (and this is preferred) formed as elongated prismatic ribs extending in parallel relation over the wall surface.
  • the discharge heat flux density pq is assumed to be uniform over the length 1 of the rib sides, and consequently also the temperature gradient is substantially uniform along the sides.
  • the flux lines, such as 11, of the input heat applied to the base of the triangle are uniformly distributed over the inclined sides of the ribs, and the temperature along each side decreases linearly from 1 to t This uniform temperature distribution is considered desirable and the corresponding gen- (III) erally triangular contour is accordingly a preferred em-,
  • the apex temperature t therefore, lies in the region B of nucleate or bubble boiling, preferably near the upper limit of this region, where the vapor nuclei tend to coalesce into large bubbles, the socalled coalescence range. Since this holds for both side surfaces of the protuberance on opposite sides from the apex thereof, and in view of the tapered shape of the protuberance, there results a situation in which the large steam bubbles generated. at the upper ends of both sidewalls of the protuberance combine into a common column of vapor 14 which is forcibly ejected from the apex of the protuberance.
  • the columns 14 of intense vaporization 9 ejected from the protuberances act to bore holes, as it were, in the body of the surrounding liquid.
  • each inclined side surface of the protuberance carries a stable temperature gradient from the root temperature t (generally approximating the Leidenfrost point t;,) to the apex temperature 1 (somewhat below the critical temperature t).
  • a major region of each side surface is exposed to the transitional or semi-film boiling conditions designated as C in FIG. 1, and a minor region of the side surface towards the apex thereof is exposed to the coalescent bubble boiling conditions designated B.
  • the junction of the two regions corresponds in temperature with that of the critical point M, as indicated.
  • FIG. 5a which coresponds to FIG. 4 of the earlier US. Patent 3,235,004
  • FIG. 5a which coresponds to FIG. 4 of the earlier US. Patent 3,235,004
  • stable temperature gradients are present throughout the extent of the walls of the heatdissipating formations.
  • Each sidewall has a continuous set of points encompassing both types of boiling to either side of the critical temperature at point M.
  • heat transfer from the metal to the fluid takes place in accordance with the boosted, socalled total heat transfer curve MRL.
  • MRL total heat transfer curve
  • a substantially uniform wetting of the wall surfaces with liquid is present, without cluttering of the interprotuberance channels with vapor.
  • the fluid circulation associated with the operation of the narrow grooved structure there disclosed involves a radial outflow of vapor from the outer ends or mouths of the channels and a simultaneous axial inflow of liquid from a longitudinal end of the channels.
  • the fluid circulation tends to assume a different pattern. This pattern involves a radial outflow of vapor from the apices of the protuberances and a simultaneous radial inflow of liquid through the outer radial ends of the channels between the protuberances (as indicated by arrows 30).
  • the protuberances may be provided in the form of continuous ribs extending the full axial length of the structure. In some cases however, the provision of such transverse channels is found beneficial in that it promotes turbulence while reducing the weight of the structure. As shown in FIG. 6, the ribs like protuberances 4, having a transverse contour of the type described above with reference to FIG. 3 or 4, are interrupted with longitudinally-spaced, transversely-extending recesses 19.
  • the transverse channels 19 are preferably V-shaped as shown, with the angle a being the same as that shown in FIG. 3.
  • the apical part of the protuberance has castellations 20, 21 formed therein by means of cuts spaced along the length of the riblike protuberance and extending from the top thereof, and preferably these castellations are alternately bent in opposite directions.
  • This increases the heat-dissipating area near the top of the protuberance and tends to lower the temperature at the apex, improving the stability of the temperature gradient.
  • FIG. 8 a generally similar result is obtained by providin an outer part 24 of the protuberance 4 of constant width instead of tapered.
  • the uniformwidth outer portion 24 should have a width less than half the base width 2a of the protuberance, so that the protuberance will still remain tapered over a major part of its length as prescribed in accordance with this invention. It is found that in such conditions the relatively enlarged outer portion 24 does not interfere with the satisfactory ejection of vapor from the apex (preferably castellated) of the protuberance as explained with reference to FIG. 5.
  • the surfaces of the outer part of the protuberance may be roughened further to increase the relative heat dissipating area thereon, and/or other of the expedients disclosed for a similar purpose in the lastmentioned patent may be applied.
  • the safety factor k is preferably taken rather large, e.g. from 1.5 to 2.
  • the factor p is equal to the ratio p q of the heat output flux density actually present in the device to the mean critical flux density as derived from Nukiyamas curve. (The critical flux density q as earlier noted is determinable for any particular fluid and under any particular pressure conditions from available tabulations, or by formulas such as Kutadeladzes formula.)
  • the factor p is in the nature of an efiiciency factor.
  • the efficiency factor p can actually be taken greater than 1, and can attain the surprisingly high value of 1.5 or 1.6.
  • a preferred range for the efliciency factor p is from 0.8 to 1.2.
  • the higher or base temperature t should, as will be understood from earlier explanations, approach the Leidenfrost point temperature t (225 C. for water at ordinary pressure). If t is taken too high above the Leidenfrost point the average value of will decrease.
  • the temperature drop 0 will be in a range of from 50 C. to 150 C. For water at ordinary pressure, a preferred range for 0 is from 80 to 120 C.
  • the invention makes it possible successfully to dissipate heat input rates substantially higher than the rates that can be dealt with by means of conventional structures, including values of exceeding the remarkably high value of 1000 watts per square centimeter. While the use of the invention is also contemplated in connection with moderate and low heat output rates, except in certain special applications some of which will be indicated later, it is generally regarded as of minor interest to use the improved structures as coolers in cases where the heat rate to be dissipated does not exceed, say, 200 watts/sq. cm. In terms of the critical flux density q, it can be stated that the invention is useful in cooling applications with input heat flux densities (p in ,a range of from 1.5q to 6g. It will be understood that for the larger heat input rates, the value of q is preferably increased through an increase in the pressure applied to the fluid.
  • the evaporating liquid medium may be provided as a generally stagnant body in an enclosure surrounding the heat dissipating structure, so that its circulation will occur by the action of natural convection; or means may be provided for inducing a forced circulation of the fluid.
  • forced circulation of the liquid (together with preferably increase pressure) is advantageously used, at a suificient flow rate to condense a major part of the vapor formed adjacent the structure. The ready inflow of the liquid radially into the inter-protuberance channels, as described earlier herein, is thereby facilitated.
  • the pitch 2a may be increased to 0.25 cm.
  • Example 2 In a cooling apparatus for a high-power vacuum tube having a total power rating of 170 kw. and an anode area of 155 cmF, it was necessary to dissipate 1100 watts/ sq. cm. over a large area.
  • the efliciency factor p is in this instance selected near the upper limit of its range, because of the high temperature gradient applied and the favourable effect of the condensation by a flow of subcooled water. Thus, p was made equal to 1.5. Equation III then provides a value 211:0.37 centimeter, for the root width of the protuberances.
  • Heat dissipating structures according to the invention are applicable over wide ranges of conditions and the protuberances or teeth thereof can correspondingly assume widely differing proportions.
  • the b dimension will be less than 0.1 cm. for temperature drops 0 in the preferred range and nominal flux density 5 on the order of 500 w. per square centimeter of the heat input surface.
  • Such structures are useful e.g. in steam generators, using boiling water at high pressure, e.g. atmospheres, having a saturation temperature z of 285 C.
  • Structures according to the invention are also usable in chemical processes as evaporators for liquids (e.g. chlorine trifluoride) having low chemical stability and poor heat transfer properties, including a very low critical flux densty q, and consequently requiring very low temperature drops 6 to be used, e.g. :20" C.
  • Stainless steel evaporators for such purposes can be constructed according to the invention for operation at a heat transfer rate of 10 w./cm. using a protuberance length b of 0.5 cm.
  • relationship (I) assumes primary importance, while relation (II) or (III) becomes relatively uncritical.
  • a non-isotherm heat dissipating structure of the type comprising a wall of heat conductive material having one side exposed to a heat source and its opposite side exposed to a vaporizable liquid and formed with protuberances adapted in operation to have substantial temperature gradients established over the side-walls thereof, the improvement characterized in that the protuberances have adjoining bases and have sidewalls that are tapered over at least a substantial part of their length, and are so proportioned as to satisfy the relations:
  • b, s, and s are the length, base area and total side surface area, respectively, of a protuberance; c is the heat conductivity of said material; q is the critical flux density of heat transfer of the boiling liquid at the pressure of operation; 0 is the specified temperature drop from the base to the apex of a protuberance in operation;
  • k is a numerical safety factor selectable within the range from 1 to 2;
  • p is a numerical efficiency factor selectable within the range from 0.8 to 1.6, the values of b, s,,, s 0, 0, as and q being expressed in units of any coherent system of measures.
  • an anisotherm heat dissipating structure of the type comprising a wall of heat conductive material having one side exposed to a heat source and its opposite side exposed to a vaporizable liquid and formed with protuberances adapted in operation to have substantial temperature gradients established over the sidewalls thereof, the improvement characterized in that the protuberances have a generally triangular contour as seen on a plane normal to said wall, with adjoining bases, and are so proportioned as to satisfy the relations:
  • c is the heat conductivity of said material
  • q is the critical flux density of heat transfer of the boilin-g liquid at the pressure of operation
  • 0 is the specified temperature drop from the base to the apex of a protuberance in operation
  • protuberances are elongated parallel ribs of uniform transverse contour.
  • protuberances are in the general form of pyramids aligned in two mutually orthogonal directions.
  • protuberances have rounded bases and apices, and wherein said relations are applied to the contour defined by the centers of curvature of said rounded bases and apices.
  • liquid is water at ordinary pressure and said temperature drop is in the range from to C.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Geometry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Plasma & Fusion (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Measuring Fluid Pressure (AREA)
US512090A 1964-12-17 1965-12-07 Anisotherm evaporation heattransfer structure Expired - Lifetime US3367415A (en)

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FR999075A FR1444696A (fr) 1964-12-17 1964-12-17 Perfectionnements apportés aux parois dissipatrices de chaleur et aux dispositifs comportant de telles parois

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AT (1) AT257543B (fr)
BE (1) BE673484A (fr)
CH (1) CH519694A (fr)
DE (1) DE1501481C3 (fr)
ES (1) ES320596A1 (fr)
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3521705A (en) * 1967-06-13 1970-07-28 Thomson Houston Comp Francaise Heat exchange structure and electron tube including such heat exchange structure
US11598518B2 (en) * 2011-05-13 2023-03-07 Rochester Institute Of Technology Devices with an enhanced boiling surface with features directing bubble and liquid flow and methods thereof

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1763698B1 (de) * 1968-07-19 1970-09-03 Bbc Brown Boveri & Cie Kuehlvorrichtung fuer selbstgekuehlte Transformatoren
US4159739A (en) * 1977-07-13 1979-07-03 Carrier Corporation Heat transfer surface and method of manufacture
AU548348B2 (en) * 1983-12-21 1985-12-05 Air Products And Chemicals Inc. Finned heat exchanger
JPS60142195A (ja) * 1983-12-28 1985-07-27 Hitachi Cable Ltd 内面溝付伝熱管
DE19963374B4 (de) * 1999-12-28 2007-09-13 Alstom Vorrichtung zur Kühlung einer, einen Strömungskanal umgebenden Strömungskanalwand mit wenigstens einem Rippenelement
EP1729079A1 (fr) * 2005-05-30 2006-12-06 Son S.R.L. Mèthode de production d'une unité d'échange de chaleur pour un générateur de vapeur à récupération de chaleur , une unité d'échange de chaleur, un générateur de vapeur à récupération de chaleur et un tube pour une unité d'échange de chaleur
CN104795115B (zh) * 2015-04-07 2017-04-12 上海交通大学 热流探头贴敷装置及方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2935305A (en) * 1950-07-07 1960-05-03 Gen Electric Electric discharge device cooling system
US2969957A (en) * 1956-01-10 1961-01-31 Thomson Houston Comp Francaise Electric discharge device cooling systems

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2935305A (en) * 1950-07-07 1960-05-03 Gen Electric Electric discharge device cooling system
US2969957A (en) * 1956-01-10 1961-01-31 Thomson Houston Comp Francaise Electric discharge device cooling systems

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3521705A (en) * 1967-06-13 1970-07-28 Thomson Houston Comp Francaise Heat exchange structure and electron tube including such heat exchange structure
US11598518B2 (en) * 2011-05-13 2023-03-07 Rochester Institute Of Technology Devices with an enhanced boiling surface with features directing bubble and liquid flow and methods thereof

Also Published As

Publication number Publication date
DE1501481B2 (de) 1979-06-13
CH519694A (fr) 1972-02-29
SE313585B (fr) 1969-08-18
IL24737A (en) 1969-11-30
OA02050A (fr) 1970-05-05
DE1501481A1 (de) 1969-09-18
BE673484A (fr) 1966-06-09
LU50058A1 (fr) 1966-02-14
FR1444696A (fr) 1966-07-08
AT257543B (de) 1967-10-10
ES320596A1 (es) 1966-06-01
DE1501481C3 (de) 1980-02-28
GB1119518A (en) 1968-07-10

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