US3762468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat transfer members
Assignee: United Kingdom Atomic Energy Authority
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Filing: 1971-06-28
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Granted: 1973-10-02
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Expires: 1991-06-28
Abstract
Abstract A special profile for the surface of a heat transfer member is described in which downwardly inclined grooves are formed with convexly curved crests whose radius of curvature decreases to a minimum at the peak where it substantially is less than the minimum radius of the adjacent troughs. A ratio of 1 : 10 is mentioned. The feature is applicable to grooves with an undercut flank on one side of the crest, useful on vertical condensing surfaces in assisting run off of condensate.
Inventors
- 👤 I Newson
- 👤 T Hodgson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:07
CPC Classifications
F; F28; F28F; F28F1/00; F28F1/10; F28F1/42; F28F1/424; F28F1/426; F28F13/00; F28F13/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
68 words
A heat transfer member having at least one surface for exposure to a heat transfer medium formed with a plurality of inclined grooves presenting a series of convexly curved crests and concavely curved troughs, the crests having a minimum radius of curvature at the peak thereof which is less than the minimum radius of curvature at the trough, the wall thickness of said member being substantially uniform throughout.
Claim 2
Dependent Claim
68 words
A heat transfer member having at least one surface for exposure to a heat transfer medium formed with a plurality of inclined grooves presenting a series of convexly curved crests and concavely curved troughs, the crests having a minimum radius of curvature at the peak thereof which is less than the minimum radius of curvature at the trough, the wall thickness of said member being substantially uniform throughout.
Claim 3
Dependent Claim
39 words
A heat transfer member as claimed in claim 1 in which the radius of curvature of the crest diminishes sharply at the apex thereof such that at that location it is less than the minimum radius at the troughs.
Claim 4
Dependent Claim
88 words
A heat transfer member as claimed in claim 1, wherein said member is a tube having a plurality of helical grooves in the outer wall thereof presenting outwardly facing crests and troughs in which the ratio of the radii of curvature of the crests to troughs is about 1 to 10 and whose bore wall Is formed with complementary grooves having adjacent inward facing troughs and crests of which the ratio of the radii of the curvature of the crests to the troughs is about 10 to 1.
Claim 5
Dependent Claim
83 words
A heat transfer member comprising a tube having its outer surface formed with multistart helical grooves which present a series of outwardly facing crests and troughs, the radius of curvature of the crests diminishing to a minimum at the peak of the crests where at the radius is less than the minimum radius of curvature at the bottom of the trough, the tube wall being of substantially uniform thickness throughout its circumference so that a substantially complementary profile appears in the tube bore.
Claim 6
Dependent Claim
83 words
A heat transfer member comprising a tube having its outer surface formed with multistart helical grooves which present a series of outwardly facing crests and troughs, the radius of curvature of the crests diminishing to a minimum at the peak of the crests where at the radius is less than the minimum radius of curvature at the bottom of the trough, the tube wall being of substantially uniform thickness throughout its circumference so that a substantially complementary profile appears in the tube bore.
Claim 7
Dependent Claim
26 words
A heat transfer member as claimed in claim 4 in which the helical grooves are formed as a multistart helix of between 10 and 25 starts.
Claim 8
Dependent Claim
24 words
A heat transfer member as claimed in claim 4 and having helical grooves formed as a multistart helix of between 16 and 20 starts.
Claim 9
Dependent Claim
93 words
A heat transfer member as claimed in claim 4 having one face thereof adapted for condensing vapour thereon, said face being disposed vertically and containing grooves extending vertically downwards and exhibiting alternately crests and troughs the crests being formed in relation to the troughs such that condensate film forming on the crests runs off into the adjacent lower trough and wherein due to the shape of the groove it runs preferentially downwards along the trough rather than on to the crest of the next lower groove, the member being of substantially uniform thickness.
Claim 10
Dependent Claim
47 words
A heat transfer member as claimed in claim 7 in which at least some of the grooves are formed of asymmetrical profile so that each crest is slightly undercut on one flank to form a condensate trap formed by the downwardly inclined grooves presenting upwardly directed crests.
Claim 11
Dependent Claim
64 words
A heat transfer member comprising a tube as claimed in claim 4 adapted for climbing film evaporator tube and comprising a helically grooved bore connected to receive in the lower region thereof a liquid to be evaporated, means supporting the tube vertically in a condensing vapour whereby heat is transferred from the condensing vapour to heat and evaporate the liquid within the tube bore.
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) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |