US3885936A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchangers
Assignee: LUND BASIL GILBERT ALFRED
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Filing: 1973-02-21
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Granted: 1975-05-27
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Expires: 1993-02-21
Abstract
Abstract A heat exchanger is composed of vertical tubes of cuspate, symmetrical aerofoil section. The chords are parallel to the air flow. The tubes are in parallel rows that interpenetrate so that each tube forms parallel-sided passages with two tubes leading it. The ratio of width to length of these passages is between 0.3 and 1.0. The tubes are spaced apart at various levels by means of inclined spacers. At the top of the tubes water may be fed around them from a launder via a system of spacers. The spacers lower down serve to redistribute the water running down the flanks of the tubes. At the base there is an inclined platform on which the water is collected and fed to a launder. This water may be recirculated with additions to replace water lost by evaporation.
Inventors
- 👤 Gerald John Nicholson Limebeer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:42
CPC Classifications
F; F28; F28F; F28F13/00; F28F13/06; F28B; F28B1/00; F28B1/06; F28D; F28D5/00; F28D5/02; F28F1/00; F28F1/02; F28F1/08; F28F21/00; F28F21/06; F28F21/067; F28F9/00; F28F9/007; F28F9/013; F28F9/0132; F28F9/02; F28F9/0219; F28F9/0221; F28F9/04; F28F9/06; F28F2225/00; F28F2250/00; F28F2250/02; F28F2275/00; F28F2275/20; F28F2275/205; Y; Y10; Y10S; Y10S165/00; Y10S165/90; Y10S261/00; Y10S261/11
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
227 words
A heat exchanger comprising a multiplicity of tubes extending between tube sheets for a first fluid to flow in the tubes and a second fluid to flow past the tubes in a direction normal to an aperture plane, and in which: a. the tubes are in a plurality of rows parallel to the aperture plane and parallel to one another; b. each tube is of a symmetrical aerofoil section with a cuspate trailing edge, with its chord plane normal to the aperture plane, is formed within a continuous aerofoil shape from end to end so that there are no heat transfer surfaces extending into the path of the second fluid, and has a fineness ratio between 6:1 and 2:1; c. the tubes are so shaped and rows of tubes are so positioned that the nose of a tube in a trailing row of tubes intercallates between the trailing edges of pairs of tubes in the leading row so that between adjacent trailing and leading tubes passages of substantially constant width along their lengths in the direction of flow of the second fluid are formed: d. each row is off-set with respect to the row leading it to such an extent that the constant width passage to one side of a tube is substantially twice the width of the constant width passage to the other side of it.
Claim 2
Dependent Claim
227 words
A heat exchanger comprising a multiplicity of tubes extending between tube sheets for a first fluid to flow in the tubes and a second fluid to flow past the tubes in a direction normal to an aperture plane, and in which: a. the tubes are in a plurality of rows parallel to the aperture plane and parallel to one another; b. each tube is of a symmetrical aerofoil section with a cuspate trailing edge, with its chord plane normal to the aperture plane, is formed within a continuous aerofoil shape from end to end so that there are no heat transfer surfaces extending into the path of the second fluid, and has a fineness ratio between 6:1 and 2:1; c. the tubes are so shaped and rows of tubes are so positioned that the nose of a tube in a trailing row of tubes intercallates between the trailing edges of pairs of tubes in the leading row so that between adjacent trailing and leading tubes passages of substantially constant width along their lengths in the direction of flow of the second fluid are formed: d. each row is off-set with respect to the row leading it to such an extent that the constant width passage to one side of a tube is substantially twice the width of the constant width passage to the other side of it.
Claim 3
Dependent Claim
55 words
The heat exchanger claimed in claim 1 in which the tubes are so shaped and positioned that any passage formed where two adjacent tubes are at their closest to one another has a ratio of width between the tubes and length in the direction of flow of the second fluid of between 0.3 and 1.0.
Claim 4
Dependent Claim
18 words
The heat exchanger claimed in claim 1 in which the fineness ratio is of the order of 4:1.
Claim 5
Dependent Claim
22 words
The heat exchanger claimed in claim 1 in which the chord length of the aerofoil section is between 25 and 75 mm.
Claim 6
Dependent Claim
22 words
The heat exchanger claimed in claim 1 in which each tube is made of sheet metal bent to form the aerofoil shape.
Claim 7
Dependent Claim
47 words
The heat exchanger claimed in claim 1 in which each tube sheet is composed of a series of parallel slats parallel to the tube rows and formed with cut-outs to fit around the tubes and a layer of concrete surrounding the tube ends passing through the slats.
Claim 8
Dependent Claim
22 words
The heat exchanger claimed in claim 6 in which there are two layers of slats with the layer of concrete between them.
Claim 9
Dependent Claim
26 words
The heat exchanger claimed in claim 1 in which the tube flanks are indented in the direction of flow of the second fluid to strengthen them.
Claim 10
Dependent Claim
58 words
The heat exchanger claimed in claim 1 in which the planes of symmetry of the tubes are vertical and the second fluid is a gas, including means for applying a liquid to the top of the exterior surfaces of the tubes for a continuous film of the liquid to form at least on the flanks of each tube.
Claim 11
Dependent Claim
57 words
The heat exchanger claimed in claim 9 including a series of spacers extending along rows of tubes, the spacers in plan forming a continuous surface but being stepped in elevation and inclined against the flow of the second fluid, and including a liquid feeding device to feed liquid evenly on to the top of the top spacer.
Claim 12
Dependent Claim
29 words
The heat exchanger claimed in claim 10 in which the spacers run parallel to the aperture plane and the top spacer is at the rear of thE heat exchanger.
Claim 13
Dependent Claim
34 words
The heat exchanger claimed in claim 11 including a channel parallel to the top spacer, an overflow weir along one edge of the channel and an apron from the weir to the top spacer.
Claim 14
Dependent Claim
30 words
The heat exchanger claimed in claim 12 including series of spacers positioned at suitable intervals down the lengths of the tubes to effect redistribution of liquid running down the tubes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |