US3664928A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dimpled heat transfer walls for distillation apparatus
Assignee: Aerojet Rocketdyne Inc
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Filing: 1969-12-15
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Granted: 1972-05-23
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Expires: 1989-12-15
Abstract
Abstract According to the present disclosure, a heat transfer wall of a distillation apparatus is dimpled so that a plurality of dimples protrude from the evaporating surface of the heat transfer wall. The dimples are preferrably arranged so that tortuous flow paths are formed between the dimples.
Inventors
- 👤 Ernest Roth Roberts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:18
CPC Classifications
F; F28; F28F; F28F3/00; F28F3/02; F28F3/04; C; C02; C02F; C02F1/00; C02F1/02; C02F1/04; C02F1/08; F28D; F28D3/00; Y; Y02; Y02A; Y02A20/00; Y02A20/124
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
205 words
In a distillation apparatus, the improvement comprising: a bundle of vertically disposed rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the metallic tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding thru the outer surface of the wall to form liquid flow paths thereon between said dimples, said dimples being structurally free of contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the metallic wall with the wall thickness td of the dimpled portions of said heat transfer wall being less than the wall thickness tu of the undimpled portions of said heat transfer wall, a first means for supplying a thin film of a liquid undergoing evaporation to the evaporating surface of said wall, and a second means for supplying a heat-transferring vapor to the condensing side of said wall, and wherein the thickness tu of the undimpled portions of said wall is between about 0.020 and 0.650 inch and the thickness td of the dimpled portion of said wall is between about 0.015 and 0.610 inch.
Claim 2
Dependent Claim
205 words
In a distillation apparatus, the improvement comprising: a bundle of vertically disposed rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the metallic tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding thru the outer surface of the wall to form liquid flow paths thereon between said dimples, said dimples being structurally free of contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the metallic wall with the wall thickness td of the dimpled portions of said heat transfer wall being less than the wall thickness tu of the undimpled portions of said heat transfer wall, a first means for supplying a thin film of a liquid undergoing evaporation to the evaporating surface of said wall, and a second means for supplying a heat-transferring vapor to the condensing side of said wall, and wherein the thickness tu of the undimpled portions of said wall is between about 0.020 and 0.650 inch and the thickness td of the dimpled portion of said wall is between about 0.015 and 0.610 inch.
Claim 3
Dependent Claim
26 words
Apparatus according to claim 1 wherein said dimples are so disposed and arranged in said array that said flow paths are tortuous in a vertical direction.
Claim 4
Dependent Claim
16 words
Apparatus according to claim 1 wherein said dimples protrude from said condensing surface of said wall.
Claim 5
Dependent Claim
16 words
Apparatus according to claim 1 wherein said dimples protrude from said evaporating surface of said wall.
Claim 6
Dependent Claim
25 words
Apparatus according to claim 4 further including a second array of a plurality of second dimples in said wall and protruding thru the inner surface.
Claim 7
Dependent Claim
34 words
Apparatus according to claim 1 wherein the inner surface has an array of a second plurality of dimples protruding inwardly therefrom to form second flow paths on said opposite surface between the second dimples.
Claim 8
Dependent Claim
27 words
Apparatus according to claim 6 wherein said second plurality of dimples are so disposed and arranged that the flow paths therebetween are tortuous in a vertical direction.
Claim 9
Dependent Claim
150 words
In a distillation apparatus, the improvement comprising: a bundle or rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding thru the outer surface to form liquid flow paths thereon between said dimples, said dimples being structurally free from contact with adjacent tubes and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall with the wall thickness td of the dimpled portions of said heat transfer wall being less than the wall thickness tu of the undimpled portions of said heat transfer wall and wherein td is approximately equal to where y is the inside sagitta of the dimples, r is the radius of the dimpling, and K is a constant.
Claim 10
Dependent Claim
150 words
In a distillation apparatus, the improvement comprising: a bundle or rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding thru the outer surface to form liquid flow paths thereon between said dimples, said dimples being structurally free from contact with adjacent tubes and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall with the wall thickness td of the dimpled portions of said heat transfer wall being less than the wall thickness tu of the undimpled portions of said heat transfer wall and wherein td is approximately equal to where y is the inside sagitta of the dimples, r is the radius of the dimpling, and K is a constant.
Claim 11
Dependent Claim
161 words
In a distillation apparatus, the improvement comprising: a bundle of rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular walls and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding thru the exterior surface to form liquid flow paths thereon, said dimples beIng structurally free from contact with adjacent tubes and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall with the wall thickness td of the dimpled portions of said heat transfer wall being less than the wall thickness tu of the undimpled portions of said heat transfer wall and wherein the smallest pitch P between adjacent dimples is between about 0.1875 and 1.250 inch, the inside sagitta y of each dimple is between about 0.0084 and 0.3875 inch, and the dimpling radius r is between about 0.0625 and 0.3875 inch.
Claim 12
Dependent Claim
161 words
In a distillation apparatus, the improvement comprising: a bundle of rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular walls and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding thru the exterior surface to form liquid flow paths thereon, said dimples beIng structurally free from contact with adjacent tubes and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall with the wall thickness td of the dimpled portions of said heat transfer wall being less than the wall thickness tu of the undimpled portions of said heat transfer wall and wherein the smallest pitch P between adjacent dimples is between about 0.1875 and 1.250 inch, the inside sagitta y of each dimple is between about 0.0084 and 0.3875 inch, and the dimpling radius r is between about 0.0625 and 0.3875 inch.
Claim 13
Dependent Claim
41 words
Apparatus according to claim 9 wherein the thickness tu of the undimpled portions of said wall is between about 0.020 and 0.650 inch and the thickness td of the dimpled portion of said wall is between about 0.015 and 0.610 inch.
Claim 14
Dependent Claim
184 words
In a distillation apparatus, the improvement comprising: a bundle of rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding radially outwardly from the exterior surface to form liquid flow paths thereon, said dimples being structurally free of contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall with the surface opposite the first surface having an array of a second plurality of dimples protruding radially inwardly therefrom to form second flow paths on said opposite surface between the second dimples and wherein the thickness of td of the dimpled portions of the heat transfer wall is less than the wall thickness tu of the undimpled portions of said wall and wherein td is approximately equal to where y is the inside sagitta of the dimples, r is the radius of the dimpling and K is a constant.
Claim 15
Dependent Claim
184 words
In a distillation apparatus, the improvement comprising: a bundle of rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding radially outwardly from the exterior surface to form liquid flow paths thereon, said dimples being structurally free of contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall with the surface opposite the first surface having an array of a second plurality of dimples protruding radially inwardly therefrom to form second flow paths on said opposite surface between the second dimples and wherein the thickness of td of the dimpled portions of the heat transfer wall is less than the wall thickness tu of the undimpled portions of said wall and wherein td is approximately equal to where y is the inside sagitta of the dimples, r is the radius of the dimpling and K is a constant.
Claim 16
Dependent Claim
169 words
In a distillation apparatus the improvement comprising: a bundle of rigid, metallic heat transfer tubes providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding radially outwardly from the outer surface to form liquid flow paths thereon between said dimples, said dimples being structurally free from contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall and wherein the inner surface has an array of a second plurality of dimples protruding radially inwardly therefrom to form second flow paths on said inner surface between the second dimples and wherein the smallest pitch P between adjacent dimples is between about 0.1875 and 1.250 inch, the inside sagitta y of each dimple is between about 0.0084 and 0.3875 inch, and the dimpling radius r is between about 0.0625 and 0.3875 inch.
Claim 17
Dependent Claim
169 words
In a distillation apparatus the improvement comprising: a bundle of rigid, metallic heat transfer tubes providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding radially outwardly from the outer surface to form liquid flow paths thereon between said dimples, said dimples being structurally free from contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall and wherein the inner surface has an array of a second plurality of dimples protruding radially inwardly therefrom to form second flow paths on said inner surface between the second dimples and wherein the smallest pitch P between adjacent dimples is between about 0.1875 and 1.250 inch, the inside sagitta y of each dimple is between about 0.0084 and 0.3875 inch, and the dimpling radius r is between about 0.0625 and 0.3875 inch.
Claim 18
Dependent Claim
169 words
In a distillation apparatus the improvement comprising: a bundle of rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding radially outwardly from outer surface to form liquid flow paths thereon between said dimples, said dimples being structurally free of contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall and wherein the interior surface has an array of a second plurality of dimples protruding radially inwardly therefrom to form second flow paths on said interior surface between the second dimples and wherein the thickness tu of the undimpled portions oF the wall is between about 0.020 and 0.650 inch and the thickness td of the dimpled portion of the wall is between about 0.015 and 0.610 inch, td being less than tu.
Claim 19
Dependent Claim
169 words
In a distillation apparatus the improvement comprising: a bundle of rigid, metallic heat transfer tubes, each providing an evaporating surface on one side of the tubular wall and a condensing surface on the other side, an array of a plurality of dimples in said tubular wall and protruding radially outwardly from outer surface to form liquid flow paths thereon between said dimples, said dimples being structurally free of contact with adjacent tubes and their dimples and suitable for the formation of thin liquid films thereover and acting to improve the heat transfer capability of the wall and wherein the interior surface has an array of a second plurality of dimples protruding radially inwardly therefrom to form second flow paths on said interior surface between the second dimples and wherein the thickness tu of the undimpled portions oF the wall is between about 0.020 and 0.650 inch and the thickness td of the dimpled portion of the wall is between about 0.015 and 0.610 inch, td being less than tu.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |