CA1239927A - High heat transfer means for flat tube and fin heat exchangers - Google Patents
High heat transfer means for flat tube and fin heat exchangersInfo
- Publication number
- CA1239927A CA1239927A CA000442524A CA442524A CA1239927A CA 1239927 A CA1239927 A CA 1239927A CA 000442524 A CA000442524 A CA 000442524A CA 442524 A CA442524 A CA 442524A CA 1239927 A CA1239927 A CA 1239927A
- Authority
- CA
- Canada
- Prior art keywords
- tubes
- fin
- heat exchanger
- tube
- fins
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- 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
- F28F1/32—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 having portions engaging further tubular elements
- F28F1/325—Fins with openings
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Geometry (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
Abstract
HIGH HEAT TRANSFER MEANS FOR FLAT
TUBE AND FIN HEAT EXCHANGERS
ABSTRACT
A high heat transfer means for a modular compact heat exchanger (10) utilizing a boundary layer control concept for a flat tube (11) and fin heat exchanger wherein the fins (12) are slit to enhance heat transfer with a low pressure drop. The fins are slit at right angles to the air flow through the unit with the slit portions raised above or lowered below the fin surface and dimensioned to reduce pressure drop and enhance heat transfer.
TUBE AND FIN HEAT EXCHANGERS
ABSTRACT
A high heat transfer means for a modular compact heat exchanger (10) utilizing a boundary layer control concept for a flat tube (11) and fin heat exchanger wherein the fins (12) are slit to enhance heat transfer with a low pressure drop. The fins are slit at right angles to the air flow through the unit with the slit portions raised above or lowered below the fin surface and dimensioned to reduce pressure drop and enhance heat transfer.
Description
3~ ~
HIG~I HEAT TRANSFER MEANS FOR FLAT
TUBE AND FIN HEAT EXCHANGERS
Description To handle high density heat loads, a heat exchanger is conventionally modified by increasing the number of fins in the heat exchange core for increased air side surface area, however, this also results in a high pressure drop for air flow through the core. Further-more, boundary layers are formed on the face of the heat exchanger fins where the air velocity and temperature are changing~ At the leading edge of the fins where air enters the heat exchanger, the boundary layer is thin and the heat transfer coefficient is large, however~ at the end of the fins, the boundary layer becomes thicker and the heat transfer coefficient from the fins to air decreases.
One method of overcoming this problem is to arrange a number of raised louvres at equal intervals on the fin surfaces to more efficiently utilize the boundary layers on the top of the fins. With the louvres, the boundary layers do not increase as much as Eor flat uninterrupted fins and the flow through the front area of the louvred fins does not substantially influence the flow through the rear area of the louvred fins.
A resulting disadvantage is that heat exchangers using louvred fins have a high air pressure loss caused by high inflow losses and by velocity gradients or shear.
.~
~3 ~
~-- 2 --Another method to attempt to solve the boundary layer problem is through the use of corrugated fins.
The corrugated fins in a heat exchanger still have a boundary layer growth as well as a separation at the curved portions, thus providing both a curvature loss and a separation loss caused by the zigzag air flows through ~he fin and tube core.
More recently, the concept of an offset slit fin was applied to improve the heat exchanger performance such as shown in U. S. Patent No. 3,916,989. This patent discloses a crossed fin-tube type heat exchanger having a plurality of round heat conductive tubes and a plurality of fins provided with several rectangular slits arranged generally transversely to the flow of lS air passing through the fins and around the tubes. The slits are formed with raised portions of the fins providing louvres to intercept the air flow lines over a wide range and prevent formation of boundary layers.
The slits may be arranged in rows between the tubes or radially extending from and positioned around each tube. ~owever, it is impossible in this heat exchanger to prevent the heat flow path through the fins from ~ being disrupted. The disruption of heat flow results in a lowering of the heat transfer coefficient.
An improved configuration of slit fins is provided in this invention to enhance heat transfer within a tube and fin core for a compact heat exchanger.
The present invention comprehends the provision of a novel heat exchanger having a row or rows of flattened tubes which are located at an angle to or parallel to :~3~
-- 3 ~
normal air flow and slit fins, wherein the flat portio of the fin between adjacent tubes has been slit and offset to produce a plurality of rectangular segments located at regular spaced intervals. The original flat Ein will thus be equipped with a chain of segments thereon, alternately unslit and offset slit, so that air flow will be repeatedly interrupted by both the slit and unslit segments. This flow interruption reduces the thermal resistance between the tube-side fluid and the fin-side fluid (air) to produce a high heat transfer.
The present invention also comprehends the provi-sion of a novel heat exchanger with slit fins wherein the direction of the slit is in line with the heat flow path because the slit fin generates discontinuity in the heat flow path across the slit.
The present invention further comprehends the provision of a novel heat exchanger utilizing slit fins with the segments formed by the slits being offset from the fin surface and dimensioned to the maximum length within the constraint oE not weakening the strength of the fin collar encompassing a tube. Also the leading and trailing edges of each firl beyond the ends of the tubes are dimensioned to be of a width substantially equal to the width of not more than a formed segment.
Further objects are to provide a construction of maximum simplicity, efficiency, economy and ease of assembly, and such further objects, advantages and capabilities as will later more fully appear and are inherently possessed thereby.
One way of carrying out the invention is described in detail below with reference to drawings which illustrate only one ~pecific embodiment, in which:-Figure 1 is an elevational view of a heat exchanger5 fin and tube core embodying the present invention.
Figure 2 is a top plan view of the fin and tube core showing the offset segments in a slit fin.
Figure 3 is a partial perspective view of a slit fin and tube showing the offset segments.
Figure 4 is a partial cross sectional view taken on the line 4-4 of Figure 2.
Figure 5 is a schematic top plan view of a modular heat exchanger with slit fins.
Figure 6 is a partial top plan view of a fin and 15 tube core having canted fins~
Figure 7 is a cross sectional view taken on the line 7-7 of Figure 6.
Figure 8 is a partial top plan view of a tube and fin heat exchanger core having two rows of offset 20 tubes.
Figure 9 is a partial cross sectional view taken on the line 9-9 of Figure 8.
~ w
HIG~I HEAT TRANSFER MEANS FOR FLAT
TUBE AND FIN HEAT EXCHANGERS
Description To handle high density heat loads, a heat exchanger is conventionally modified by increasing the number of fins in the heat exchange core for increased air side surface area, however, this also results in a high pressure drop for air flow through the core. Further-more, boundary layers are formed on the face of the heat exchanger fins where the air velocity and temperature are changing~ At the leading edge of the fins where air enters the heat exchanger, the boundary layer is thin and the heat transfer coefficient is large, however~ at the end of the fins, the boundary layer becomes thicker and the heat transfer coefficient from the fins to air decreases.
One method of overcoming this problem is to arrange a number of raised louvres at equal intervals on the fin surfaces to more efficiently utilize the boundary layers on the top of the fins. With the louvres, the boundary layers do not increase as much as Eor flat uninterrupted fins and the flow through the front area of the louvred fins does not substantially influence the flow through the rear area of the louvred fins.
A resulting disadvantage is that heat exchangers using louvred fins have a high air pressure loss caused by high inflow losses and by velocity gradients or shear.
.~
~3 ~
~-- 2 --Another method to attempt to solve the boundary layer problem is through the use of corrugated fins.
The corrugated fins in a heat exchanger still have a boundary layer growth as well as a separation at the curved portions, thus providing both a curvature loss and a separation loss caused by the zigzag air flows through ~he fin and tube core.
More recently, the concept of an offset slit fin was applied to improve the heat exchanger performance such as shown in U. S. Patent No. 3,916,989. This patent discloses a crossed fin-tube type heat exchanger having a plurality of round heat conductive tubes and a plurality of fins provided with several rectangular slits arranged generally transversely to the flow of lS air passing through the fins and around the tubes. The slits are formed with raised portions of the fins providing louvres to intercept the air flow lines over a wide range and prevent formation of boundary layers.
The slits may be arranged in rows between the tubes or radially extending from and positioned around each tube. ~owever, it is impossible in this heat exchanger to prevent the heat flow path through the fins from ~ being disrupted. The disruption of heat flow results in a lowering of the heat transfer coefficient.
An improved configuration of slit fins is provided in this invention to enhance heat transfer within a tube and fin core for a compact heat exchanger.
The present invention comprehends the provision of a novel heat exchanger having a row or rows of flattened tubes which are located at an angle to or parallel to :~3~
-- 3 ~
normal air flow and slit fins, wherein the flat portio of the fin between adjacent tubes has been slit and offset to produce a plurality of rectangular segments located at regular spaced intervals. The original flat Ein will thus be equipped with a chain of segments thereon, alternately unslit and offset slit, so that air flow will be repeatedly interrupted by both the slit and unslit segments. This flow interruption reduces the thermal resistance between the tube-side fluid and the fin-side fluid (air) to produce a high heat transfer.
The present invention also comprehends the provi-sion of a novel heat exchanger with slit fins wherein the direction of the slit is in line with the heat flow path because the slit fin generates discontinuity in the heat flow path across the slit.
The present invention further comprehends the provision of a novel heat exchanger utilizing slit fins with the segments formed by the slits being offset from the fin surface and dimensioned to the maximum length within the constraint oE not weakening the strength of the fin collar encompassing a tube. Also the leading and trailing edges of each firl beyond the ends of the tubes are dimensioned to be of a width substantially equal to the width of not more than a formed segment.
Further objects are to provide a construction of maximum simplicity, efficiency, economy and ease of assembly, and such further objects, advantages and capabilities as will later more fully appear and are inherently possessed thereby.
One way of carrying out the invention is described in detail below with reference to drawings which illustrate only one ~pecific embodiment, in which:-Figure 1 is an elevational view of a heat exchanger5 fin and tube core embodying the present invention.
Figure 2 is a top plan view of the fin and tube core showing the offset segments in a slit fin.
Figure 3 is a partial perspective view of a slit fin and tube showing the offset segments.
Figure 4 is a partial cross sectional view taken on the line 4-4 of Figure 2.
Figure 5 is a schematic top plan view of a modular heat exchanger with slit fins.
Figure 6 is a partial top plan view of a fin and 15 tube core having canted fins~
Figure 7 is a cross sectional view taken on the line 7-7 of Figure 6.
Figure 8 is a partial top plan view of a tube and fin heat exchanger core having two rows of offset 20 tubes.
Figure 9 is a partial cross sectional view taken on the line 9-9 of Figure 8.
~ w
2~
Referring more particularly to the disclosure in the drawings wherein are shown illustrative embodiments of the present invention~ Figures 1 through 4 disclose a tube and fin core 10 for a compact downflow heat exchanger wherein upper and lower tan~s and tube sheets (not shown) are secured at the ends of the core to provide for fluid flow therethrough. The core consists of a plurality of flattened tubes 11 arranged in a row~
as seen in Figure 2, and a plurality of flat metal fins 12 formed out of a material, such as copper, steel or aluminum. Each fin is provided with elongated openings 13 having swaged collars 14 receiving and closely contacting the tubes 11, the collars being soldered to the tubes to provide a low resistance to heat transfer from tube to fin.
Each fin has a plurality of slits 15 with the rectangular segments 16 formed between pairs of paral-lel slits being offset from the surface of the fin by bridging sections 17 at the ends. The width L of each segment is equal to the distance T between the offset segments 16 in a row between adjacent tubes. The flat fin will thus be equipped with a chain of segments 16 extending between adjacent tubes, with the fin being alternately unslit and offset slit. Therefore, as seen in Figure 4, air flow through the core 10 will be interrupted repeatedly by both the offset segments 16 and the unslit segments 18. This repeated flow inter ruption reduces the thermal resistance between the tube-side liquid flow and the fin-side fluid; e.g.
air, thus producing high heat transfer.
The slits 15 in the fin 12 are extended to their maximum length between the tubes 11, only limited by the constraint that the slit will not weaken the strength of the fin collar 14, so that the air flow is across the 5 entire slit and substantially the length between adja-cent tubes. Also, the leading and trailing edges 19 and 21, respectively, of the fin beyond the ends 22 of the flattened tube are of a width M equal to the segment width L. Also, no slits 15 are forrned in the fin lO beyond the tube edges 22 in the region of inactive fin material, but the leading and trailing slits are sub-stantially flush with the tube ends 22. This limitation is important because, if the leading and trailing edges of the fin are deep, and more than one slit is made beyond the front and the back of the tube edges, air flow tends to bypass the slit portion and take the flow path oE least flow resistance; hence, not utilizing the slit fin advantage. Further, heat flow will be greatly obstructed due to an~ slits in the inactive fin region of the leading and trailing edges.
Manufacture of the slit fins would appear to be a problem due to probable sticking tendency of the fin to the stamping of the slits and forming the offset segments. It is suggested that a remedy for this problem would be to accomplish the slit making in the following steps: 1) hold the flat portion of the fin, 2) form the slits and oEfset segments with a cutting and offsetting die, and 3) release the cutting die from the slits while the flat portion of the fin is still under pressure. When the tubes and fins are assembled, the tubes are inserted into the aliyned openings 13 of the fin stack defined by the collars 14 and suitably soldered therein.
Figure 5 discloses a modular heat exchanger ~5 to which the slit fin concept is applied. To support the merit of the slit fin, tests were conducted on a three segment slit fin with a 15 canted tube. Results of these tests indicate that the slit fin has a 40% im-provement in heat transfer coefficient over a corres-ponding flat fin at the normal face velocity of 528 feet per minute. The slit fin performance will, in prin-ciple, further increase as the number of slits in the fin increase.
Figures 6 and 7 relate to a single tube row and slit fin heat exchanger 27 having a multiplicity of slits 32 and canted flat tubes 2~. The slits 32 are parallel with the leading edge 31 of each fin 29 and the offset segments 33 are generallv oriented in the same angular configuration as the canted tubes. As in the previous embodiments, the heat flow path in the fin 2~
is undisturbed by the slits, yet the air flow crosses the slits at 90 everywhere in the heat exchanger, thus utilizing the advantage of the slit fin more efficiently.
Figures 8 and 9 disclose another embodiment of heat exchanger 35 having two rows of tubes 36 and 37 with the tubes 35 in one row being offset from the tubes 37 in the other row as seen in Figure 8. A multiplicity of fins 38 have openings receiviny the tubes and rows of slits 39 and 41 between the adjacent tubes of each row.
The slits form segments 42 and 43 offset from the surface 44 of the fin; the segments 42 between the tubes 35 being offset from the segments 43 between the tubes 37.
Referring more particularly to the disclosure in the drawings wherein are shown illustrative embodiments of the present invention~ Figures 1 through 4 disclose a tube and fin core 10 for a compact downflow heat exchanger wherein upper and lower tan~s and tube sheets (not shown) are secured at the ends of the core to provide for fluid flow therethrough. The core consists of a plurality of flattened tubes 11 arranged in a row~
as seen in Figure 2, and a plurality of flat metal fins 12 formed out of a material, such as copper, steel or aluminum. Each fin is provided with elongated openings 13 having swaged collars 14 receiving and closely contacting the tubes 11, the collars being soldered to the tubes to provide a low resistance to heat transfer from tube to fin.
Each fin has a plurality of slits 15 with the rectangular segments 16 formed between pairs of paral-lel slits being offset from the surface of the fin by bridging sections 17 at the ends. The width L of each segment is equal to the distance T between the offset segments 16 in a row between adjacent tubes. The flat fin will thus be equipped with a chain of segments 16 extending between adjacent tubes, with the fin being alternately unslit and offset slit. Therefore, as seen in Figure 4, air flow through the core 10 will be interrupted repeatedly by both the offset segments 16 and the unslit segments 18. This repeated flow inter ruption reduces the thermal resistance between the tube-side liquid flow and the fin-side fluid; e.g.
air, thus producing high heat transfer.
The slits 15 in the fin 12 are extended to their maximum length between the tubes 11, only limited by the constraint that the slit will not weaken the strength of the fin collar 14, so that the air flow is across the 5 entire slit and substantially the length between adja-cent tubes. Also, the leading and trailing edges 19 and 21, respectively, of the fin beyond the ends 22 of the flattened tube are of a width M equal to the segment width L. Also, no slits 15 are forrned in the fin lO beyond the tube edges 22 in the region of inactive fin material, but the leading and trailing slits are sub-stantially flush with the tube ends 22. This limitation is important because, if the leading and trailing edges of the fin are deep, and more than one slit is made beyond the front and the back of the tube edges, air flow tends to bypass the slit portion and take the flow path oE least flow resistance; hence, not utilizing the slit fin advantage. Further, heat flow will be greatly obstructed due to an~ slits in the inactive fin region of the leading and trailing edges.
Manufacture of the slit fins would appear to be a problem due to probable sticking tendency of the fin to the stamping of the slits and forming the offset segments. It is suggested that a remedy for this problem would be to accomplish the slit making in the following steps: 1) hold the flat portion of the fin, 2) form the slits and oEfset segments with a cutting and offsetting die, and 3) release the cutting die from the slits while the flat portion of the fin is still under pressure. When the tubes and fins are assembled, the tubes are inserted into the aliyned openings 13 of the fin stack defined by the collars 14 and suitably soldered therein.
Figure 5 discloses a modular heat exchanger ~5 to which the slit fin concept is applied. To support the merit of the slit fin, tests were conducted on a three segment slit fin with a 15 canted tube. Results of these tests indicate that the slit fin has a 40% im-provement in heat transfer coefficient over a corres-ponding flat fin at the normal face velocity of 528 feet per minute. The slit fin performance will, in prin-ciple, further increase as the number of slits in the fin increase.
Figures 6 and 7 relate to a single tube row and slit fin heat exchanger 27 having a multiplicity of slits 32 and canted flat tubes 2~. The slits 32 are parallel with the leading edge 31 of each fin 29 and the offset segments 33 are generallv oriented in the same angular configuration as the canted tubes. As in the previous embodiments, the heat flow path in the fin 2~
is undisturbed by the slits, yet the air flow crosses the slits at 90 everywhere in the heat exchanger, thus utilizing the advantage of the slit fin more efficiently.
Figures 8 and 9 disclose another embodiment of heat exchanger 35 having two rows of tubes 36 and 37 with the tubes 35 in one row being offset from the tubes 37 in the other row as seen in Figure 8. A multiplicity of fins 38 have openings receiviny the tubes and rows of slits 39 and 41 between the adjacent tubes of each row.
The slits form segments 42 and 43 offset from the surface 44 of the fin; the segments 42 between the tubes 35 being offset from the segments 43 between the tubes 37.
Claims (11)
1. A tube and plate fin heat exchanger comprising a plurality of parallel-sided flattened tubes in at least one laterally extending row, and a plurality of closely spaced parallel plate fins having openings therein sealingly receiving said tubes, the flattened sides of adjacent tubes being sub-stantially parallel so that air flow through the fins is substantially parallel to the flattened sides, each fin having a plurality of substantially parallel slits therein perpendicular to the flattened sides and defining a plurality of segments off-set from the surface of the fin located between adjacent tubes, the width of each segment being equal to the width of the alternating fin portion intermediate said offset segments, said slits terminating closely adjacent to said tubes whereby maximum flow interruption will be obtained to reduce the thermal resis-tance thereof and to produce high heat transfer.
2. A tube and plate fin heat exchanger as set forth in
2. A tube and plate fin heat exchanger as set forth in
claim 2, in which said tubes are soldered in the openings in the fins to promote low resistance to heat transfer therebetween.
3. A tube and plate fin heat exchanger as set forth in claim 1, in which said slits are not located beyond the ends of the tubes in the row.
4. A tube and plate fin heat exchanger as set forth in claim 1, in which the leading and trailing edges of said fins extend beyond the ends of said tubes a distance not greater than the width of said offset fin segments.
5. A tube and plate fin heat exchanger as set forth in claim 1, in which said slits and offset fin segments provide a relatively low pressure drop for air flow thereacross.
6. A tube and plate fin heat exchanger as set forth in claim 1, in which said row of flattened tubes are canted relative to the longitudinal axes of said fins.
7. A tube and plate fin heat exchanger as set forth in claim 1, in which several heat exchanger sections, each having a row of flattened tubes and a plurality of fins, are arranged in angular relation to each other to form a module.
8. A tube and plate fin heat exchanger as set forth in claim 1, in which two rows of flattened tubes are received in complementary openings in said plurality of fins, and a plura-lity of slits defining offset fin segments are positioned between adjacent tubes in each row so as not to disrupt the heat path.
9. A tube and plate fin heat exchanger as set forth in claim 8, in which the tubes in the two rows are laterally off-set to each other, and the offset segments in each tube row are offset to each other.
10. A tube and plate fin heat exchanger as set forth in claim 1, wherein the slits are of identical length to the maximum length between adjacent tubes.
11. A method of manufacturing a tube and fin heat exchanger comprising the steps of selecting a thin metal fin, holding the flat portion of the fin, forming slits and offset segments with a cutting and offsetting die, releasing the cutting die from the slits while the flat portion of the fin is still under pressure, providing openings in the fins, assembling the fins in parallel relationship with the openings in alignment, inserting the tubes into the aligned openings of the fins and suitably soldering the tubes to the collars formed around the openings.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US45255882A | 1982-12-23 | 1982-12-23 | |
| US452,558 | 1982-12-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1239927A true CA1239927A (en) | 1988-08-02 |
Family
ID=23796948
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000442524A Expired CA1239927A (en) | 1982-12-23 | 1983-12-05 | High heat transfer means for flat tube and fin heat exchangers |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS59134490A (en) |
| CA (1) | CA1239927A (en) |
| DE (1) | DE3346468A1 (en) |
| FR (1) | FR2538525A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2169694B (en) * | 1985-01-15 | 1988-01-20 | Sanden Corp | Serpentine heat exchanger |
| US20110120177A1 (en) * | 2007-12-18 | 2011-05-26 | Kirkwood Allen C | Heat exchanger for shedding water |
| CN114654674B (en) * | 2022-04-05 | 2023-03-10 | 东台迈盛智能科技有限公司 | Aerogenerator blade mould of built-in rapid cooling mechanism |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1017246A (en) * | 1963-09-04 | 1966-01-19 | Ford Motor Co | Improvements in or relating to heat exchangers |
| FR1494409A (en) * | 1965-10-24 | 1967-09-08 | Borg Warner | heat exchanger and process and equipment for its manufacture |
| FR1521499A (en) * | 1967-03-07 | 1968-04-19 | Chausson Usines Sa | Fin for radiator bundle with tubes and fins |
| FR2069888A1 (en) * | 1969-12-01 | 1971-09-10 | Olofstroem Ab | |
| NL7314929A (en) * | 1973-10-31 | 1975-05-02 | Philips Nv | HEAT EXCHANGER. |
| GB2027533B (en) * | 1978-05-31 | 1982-12-22 | Covrad Ltd | Heat exchangers |
-
1983
- 1983-12-05 CA CA000442524A patent/CA1239927A/en not_active Expired
- 1983-12-09 FR FR8319786A patent/FR2538525A1/en active Pending
- 1983-12-22 JP JP24307783A patent/JPS59134490A/en active Pending
- 1983-12-22 DE DE19833346468 patent/DE3346468A1/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| DE3346468A1 (en) | 1984-07-05 |
| JPS59134490A (en) | 1984-08-02 |
| FR2538525A1 (en) | 1984-06-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6273183B1 (en) | Heat exchanger turbulizers with interrupted convolutions | |
| CA2050281C (en) | Heat exchangers | |
| EP0319451B1 (en) | Lanced sine-wave heat exchanger | |
| CA1064902A (en) | Heat exchange device | |
| US8453719B2 (en) | Heat transfer surfaces with flanged apertures | |
| EP2810010B1 (en) | Multiple tube bank heat exchanger assembly and fabrication method | |
| US5062475A (en) | Chevron lanced fin design with unequal leg lengths for a heat exchanger | |
| JP3974526B2 (en) | Heat exchanger with brazing plate | |
| KR950025409A (en) | Plate Fins for Heat Exchangers and Heat Exchangers | |
| CN111433552A (en) | Enhanced heat transfer surface | |
| US20090260789A1 (en) | Heat exchanger with expanded metal turbulizer | |
| US5117902A (en) | Fin tube heat exchanger | |
| AU708247B2 (en) | Plate-type heat exchanger with distribution zone | |
| US5975200A (en) | Plate-fin type heat exchanger | |
| CA1239927A (en) | High heat transfer means for flat tube and fin heat exchangers | |
| WO2014126634A1 (en) | Multiple bank flattened tube heat exchanger | |
| EP1007893B1 (en) | Heat exchanger turbulizers with interrupted convolutions | |
| US5476140A (en) | Alternately staggered louvered heat exchanger fin | |
| EP0803695B1 (en) | Plate-fin heat exchanger | |
| EP2064509B1 (en) | Heat transfer surfaces with flanged apertures | |
| JPS63131993A (en) | Heat exchanger | |
| JP2512981Y2 (en) | Corrugated fin type heat exchanger | |
| JPS63254396A (en) | Finned heat exchanger | |
| GB2168139A (en) | Improvements relating to plate type heat exchangers | |
| JPS644118B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |