US3570471A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiant tube having uniform high-temperature distribution
Assignee: Thermo Fisher Scientific Inc
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Filing: 1969-02-14
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Granted: 1971-03-16
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Expires: 1989-02-14
Abstract
Abstract Radiant tube heating apparatus in which rotation is imparted to a fuel-air mixture in a burner head and in which rotation continues after ignition as the flue gases travel in a helical path down the radiant tube. The continuing rotary action disrupts boundary layers permitting efficient heat transfer from flue gases to radiant tube, and further provides uniform temperature distribution along the tube. The rotation is initiated by helical channels formed in the peripheral surface of the burner head. Air is forced through those channels at high velocity and fuel is fed through the interior of the head and into the channels at right angles through a series of spaced orifices. The resultant complete mixing followed by near-adiabatic combustion create extremely high flame temperatures resulting in high radiant tube temperatures and high heat fluxes and heat release rates.
Inventors
- 👤 Lazaros J Lazaridis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:21
CPC Classifications
F; F23; F23C; F23C3/00; F23C3/002
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
78 words
In heating apparatus for a generally cylindrical radiant tube, a burner disposed axially of said tube for the combustion of a fuel mix, a sleeve closely surrounding said burner, helical channels being formed at the interface of said sleeve and said burner, means for forcing air through said helical channels and means for introducing fuel at right angles into said channels whereby products of combustion are formed into streams of flue gases proceeding helically through said radiant tube.
Claim 2
Dependent Claim
78 words
In heating apparatus for a generally cylindrical radiant tube, a burner disposed axially of said tube for the combustion of a fuel mix, a sleeve closely surrounding said burner, helical channels being formed at the interface of said sleeve and said burner, means for forcing air through said helical channels and means for introducing fuel at right angles into said channels whereby products of combustion are formed into streams of flue gases proceeding helically through said radiant tube.
Claim 3
Dependent Claim
142 words
In heating apparatus for a generally cylindrical radiant tube, a burner disposed axially of said tube, a source of fuel, a source of air, said burner being hollow, and disposed adjacent an end of said radiant tube, said burner having a first plurality of helical channels formed on the outer surface thereof and a second plurality of radial openings formed therethrough, said openings being disposed at spaced points in said channels, means for forcing air from said source thereof through said helical channels and means for forcing gas from said source thereof through said radial openings to obtain a mixture of said air and gas in said channels and to impart rotation to said mixture, and means disposed adjacent said burner for igniting said mixture to form said rotating mixture into said stream of flue gases proceeding helically through said radiant tube.
Claim 4
Dependent Claim
142 words
In heating apparatus for a generally cylindrical radiant tube, a burner disposed axially of said tube, a source of fuel, a source of air, said burner being hollow, and disposed adjacent an end of said radiant tube, said burner having a first plurality of helical channels formed on the outer surface thereof and a second plurality of radial openings formed therethrough, said openings being disposed at spaced points in said channels, means for forcing air from said source thereof through said helical channels and means for forcing gas from said source thereof through said radial openings to obtain a mixture of said air and gas in said channels and to impart rotation to said mixture, and means disposed adjacent said burner for igniting said mixture to form said rotating mixture into said stream of flue gases proceeding helically through said radiant tube.
Claim 5
Dependent Claim
45 words
In heating apparatus as defined in claim 2, the combination in which said burner is generally cylindrical in cross section and which further includes a sleeve having substantially the same internal diameter as said radiant tube surrounding said burner and aligned with said radiant tube.
Claim 6
Dependent Claim
27 words
In heating apparatus as defined in claim 2, the combination wherein said helical channels are at an angle of approximately 60* to the axis of said burner.
Claim 7
Dependent Claim
51 words
In heating apparatus as defined in claim 3, the combination which includes means connecting the interior of said burner head to said source of fuel and means connecting the interior of said sleeve to said source of air, the flow of said air providing a cooling effect to said connecting means.
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) | 1974-03-15 | 1974-09-14 | 1975-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-15 | 1978-09-14 | 1979-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-15 | 1982-09-14 | 1983-03-16 | $7700.00 | Window Closed / Lapsed |