Spiral heat exchanger coils

Abstract

Interlaced tubing elements form a spiral shaped heat exchange element. The tubing elements are tilted while being helically wound, forming a substantially overall cylinder or cone spiral structure having a central longitudinal axis. Tubing elements are tilted with respect to the central longitudinal axis, and may be continuously tilted or variably tilted. A heat exchange element is formed by a continuous tubing element that spirals around a central longitudinal axis, or by several interlaced tubing elements that are spaced adjacent to each other in a conic spiral shape. The tubing elements may have a plurality of fins on at least one of the outer surfaces or first and/or second side walls.

Claims

1. Apparatus comprising a heat exchanger, further comprising a long tube having a cross-section that is relatively wide and relatively thin, having an inner space, outer side surfaces that are relatively wide and edge surfaces that are relatively narrow between the side surfaces, the tube having a first end and a second end adapted for passing a first heat exchange fluid into the first end through the tube and out through the second end and flowing a second heat exchange fluid over the outer side surfaces, wherein the tube is progressively variably tilted continuously along an entire length of the tube and formed into a spiral about a longitudinal central axis with spaced portions of the outer side surfaces of the tube for flowing the second heat exchange fluid in spaces formed between the spaced portions of the outer side surfaces of the tube.

2. The apparatus of claim 1, wherein the spiral is formed as a cylinder around the longitudinal central axis.

3. The apparatus of claim 1, wherein the spiral is formed about the central axis and the tube is constantly receding from or moving towards the central axis.

4. The apparatus of claim 3, wherein the spiral is formed as a conical shape having spaces between the spaced portions of the outer side surfaces.

5. The apparatus of claim 4, wherein the spaced portions of the outer side surfaces of the long tube extend through the conical shape.

6. Apparatus comprising a heat exchanger, further comprising a long tube having a cross-section that is relatively wide and relatively thin, having an inner space, outer side surfaces that are relatively wide and edge surfaces that are relatively narrow between the side surfaces, the tube having a first end and a second end adapted for passing a first heat exchange fluid into the first end through the tube and out through the second end and flowing a second heat exchange fluid over the outer side surfaces, wherein the tube is progressively variably tilted continuously along an entire length of the tube and formed into a spiral about a longitudinal central axis with spaced portions of the outer side surfaces of the tube for flowing the second heat exchange fluid in spaces formed between the spaced portions of the outer side surfaces of the tube, wherein the long tube is twisted around a longitudinal axis of the tube, wherein slope angles of portions of the outer side surfaces of the tube vary with respect to the longitudinal central axis of the conical shape.

7. The apparatus of claim 6, wherein the angles of the slope vary according to positions of the portions of the outer side surfaces with respect to the central axis.

8. The apparatus of claim 4, wherein the conical shape has a first smaller diameter end and a second larger diameter end, and wherein the portions of the outer side surfaces near the first smaller diameter end form smaller acute angles to the longitudinal central axis of the conical shape, and the portions of the outer side surfaces adjacent the second larger diameter end form larger acute angles with respect to the longitudinal central axis, so that the outer side surfaces are more nearly parallel with the longitudinal central axis near the smaller diameter end and that the outer side surfaces are more nearly perpendicular to the longitudinal central axis near the larger diameter end.

9. The apparatus of claim 8, wherein the second heat transfer fluid flows inward through the spaces portions between the outer side surfaces in the conical shape of the tube in the conical shape near the first end in a direction more axial than radial to the longitudinal central axis, and wherein the second heat transfer fluid flows inward through the spaces portions between the outer side surfaces in the conical shape near the second end in a direction more radial than axial to the longitudinal central axis.

10. The apparatus of claim 8, wherein angles of the portions of the outer side surfaces nearer the first smaller diameter end of the conical shape are more axial to the longitudinal central axis, and wherein angles of the portions of the outer side surfaces nearer the second larger diameter end of the conical shape are more radial than axial to the longitudinal central axis.

11. The apparatus of claim 10, further comprising multiple interlaced tubes having similar shapes extending parallel to and spaced from each other, having first ends of the tubes near the first smaller end of the conical shape, and having second ends of the tubes near the second larger end of the conical shape.

12. The apparatus of claim 11, wherein the multiple interlaced tubes have air foil shaped surfaces with rounded leading edges of the edge surfaces facing outward from the conical shape, increased thickness central portions and tapered trailing edges facing inward in the conical shape.

13. The apparatus of claim 11, wherein the multiple interlaced tubes have rectangular cross-sections with rounded outward leading edges and rounded inward trailing edges.

14. The apparatus of claim 11, wherein the multiple interlaced tubes have inward sloped dividers forming inner micro channels in the tubes.

15. The apparatus of claim 11, wherein the multiple interlaced tubes have inward extending outer surfaces joined together at spaced positions along widths of the tubes and forming inner micro channels and outer channels between the inner micro channels.

16. The apparatus of claim 11, further comprising fins connected to the outer side surfaces of the tubes and extending into the spaces between the tubes.

17. The apparatus of claim 16, wherein the fins are angularly positioned with respect to longitudinal directions of the tubes.

18. The apparatus of claim 16, further comprising covers on the fins, wherein the covers are spaced from the outer side surfaces of the tubes.

19. The apparatus of claim 18, wherein the covers are parallel to the outer side surfaces of the tubes.

20. The apparatus of claim 11, wherein each of the multiple tubes extends around a fraction of a complete 360 turn around the conical structure.

21. Apparatus comprising a heat exchanger, further comprising multiple interlaced long tubes having cross-sections that are relatively wide and relatively thin, the tubes having inner spaces, outer side surfaces being relatively wide and edge surfaces being relatively narrow, the long tubes having first ends and second ends adapted for passing a first heat exchange fluid into the first ends, through the tubes and out of the second ends, wherein the interlaced tubes are progressively variably tilted continuously along entire lengths of the tubes and formed into a spiral having a central longitudinal axis, and wherein outer side surfaces of the interlaced tubes are spaced apart and are tilted with respect to the central axis for flowing the second heat exchange fluid over the spaced outer side surfaces and through spaces formed between the outer side surfaces of the tubes.

22. The apparatus of claim 21, wherein the spiral is formed as a cylinder around the longitudinal central axis.

23. The apparatus of claim 21, wherein the spiral is formed about and constantly receding from or moving towards the longitudinal central axis.

24. The apparatus of claim 23, wherein the spiral is formed in a conical shape, and wherein the outer surfaces of the long multiple interlaced tubes extend through the conical shape.

25. The apparatus of claim 21, wherein the long tubes are twisted around longitudinal axes of the tubes, wherein angles of slopes of portions of the outer side surfaces of the tubes vary with respect to varied positions along the longitudinal central axis of the conical shape, wherein the conical shape has a first smaller diameter end and a second larger diameter end, and wherein the portions of the outer side surfaces near the first smaller diameter end are at smaller acute angles to the central axis and the portions of the outer surfaces near the second larger diameter end are at larger acute angles with respect to the longitudinal central axis, wherein angles of the portions of the outer side surfaces nearer the first smaller diameter end of the conical shape are more axial than radial to the central axis, and wherein angles of the portions of the outer side surfaces nearer the second larger diameter end of the conical shape are more radial than axial to the longitudinal central axis, whereby the second heat transfer fluid flows inward through spaces between outer side surfaces of the tubes near the first smaller diameter end of the conical shape in a direction more axial than radial to the longitudinal central axis, and wherein the second heat transfer fluid flows inward through spaces between outer side surfaces near the second larger diameter end of the conical shape in a direction more radial than axial to the central axis.

26. A method comprising providing a heat exchanger, further comprising providing multiple spaced apart interlaced long tubes having cross-sections that are relatively wide and relatively thin, the tubes having inner spaces, relatively wide outer side surfaces and relatively narrow outer edge surfaces and having first ends and second ends tilting the interlaced tubes and forming the interlaced tubes into a spiral shape, a central longitudinal axis, and having a smaller first end and a larger second end, outer side surfaces of the interlaced tubes are spaced apart and the tubes are progressively variably tilted continuously along entire lengths of the tubes, passing a first heat exchange fluid into the first ends, through the tubes and out of the second ends, flowing the second heat exchange fluid over the spaced outer side surfaces and through spaces formed between the spaced outer side surfaces of the tubes and in a direction of the central axis and outward through the second larger end.

27. The method of claim 26, wherein the tilting further comprises tilting the outer side surfaces of the tubes with respect to the central axis.

28. The method of claim 26, further comprising twisting the long tubes about longitudinal axes of the tubes before interlacing the tubes.

29. The method of claim 26, wherein the tilting further comprises varying the tilting of the outer side surfaces.

30. The method of claim 29, wherein the tilting further comprises tilting the outer side surfaces of the tube at increasing obtuse angles and decreasing acute angles from the larger second end to the smaller first end.

31. The method of claim 26, further comprising providing the interlaced tubes in a spiral having a conical shape.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a tubing element according to the present invention in a first embodiment of a continuously tilted and twisted spiral.

(2) FIG. 2 is a further perspective view of tubing element shown in FIG. 1 showing the radii and angles for the tubing element.

(3) FIG. 3 is a further perspective view of tubing element shown in FIG. 1 showing the angles for the slope and the tilt of the tubing element.

(4) FIG. 4 is a side elevation view of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(5) FIG. 5 is an isometric view of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(6) FIG. 6 shows a comparison of the side elevation and isometric views of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(7) FIG. 7 is a cut elevation view of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(8) FIG. 8 is a perspective view of a tubing element with several alternatives for the internal structure of the tubing element.

(9) FIG. 9 is a top view of a constantly tilted spiral tubing element.

(10) FIG. 10 is a top view comparison of a constantly tilted tubing element and a conic spiral coil formed by various interlaced constantly tilted tubing elements.

(11) FIG. 11 is a side view of a conic spiral coil formed by various interlaced constantly tilted tubing elements.

(12) FIG. 12 is an isometric view of a conic spiral coil formed by various interlaced constantly tilted tubing elements.

(13) FIG. 13 is a comparison of a side view and an isometric view of a conic spiral coil formed by various interlaced constantly tilted tubing elements.

(14) FIG. 14 is a comparison of a continuously tilted tubing element and a cut view of a continuously tilted conic spiral coil.

(15) FIG. 15 is a cross-sectional view of a continuously tilted conic spiral coil showing an angle for the tilt of the coil.

(16) FIG. 16 is a comparison between two continuously tilted conic spiral coil with the same upper diameter and different lower diameters.

(17) FIG. 17 is a perspective view of a tubing element according to the present invention in a second embodiment of a variably tilted spiral.

(18) FIG. 18 is a further perspective view of tubing element shown in FIG. 17, showing the radii and angles for the tubing element.

(19) FIG. 19 is a further perspective view of tubing element shown in FIG. 17, showing the angles for the slope and the tilt of the tubing element.

(20) FIG. 20 is a side elevation view of a variably tilted tube in a continuous loop forming a conic spiral coil.

(21) FIG. 21 is an isometric view of a variably tilted tube in a continuous loop forming a conic spiral coil.

(22) FIG. 22 shows a comparison of the side elevation and isometric views of a variably tilted tube in a continuous loop forming a conic spiral coil.

(23) FIG. 23 is a cut elevation view of a variably tilted tube in a continuous loop forming a conic spiral coil.

(24) FIG. 24 is a top perspective view of a variably tilted tubing element.

(25) FIG. 25 is a top view comparison of a variably tilted tubing element and a conic spiral coil formed by various interlaced variably tilted tubing elements.

(26) FIG. 26 is a side view of a conic spiral coil formed by various interlacing variably tilted tubing elements.

(27) FIG. 27 is an isometric view of a conic spiral coil formed by various interlaced variably tilted tubing elements.

(28) FIG. 28 is a comparison of a side view and an isometric view of a conic spiral coil formed by various interlaced variably tilted tubing elements.

(29) FIG. 29 is a comparison of a variably tilted tubing element and a cut view of a variably tilted conic spiral coil.

(30) FIG. 30 is a cross-sectional view of a variably tilted conic spiral coil showing an angle for the tilt of the coil.

(31) FIG. 31 is a comparison of a continuously tilted tubing element and a twisted and variably tilted tubing element.

(32) FIG. 32 is a top view comparison of a continuously tilted tubing element and a twisted and variably tilted tubing element.

(33) FIG. 33 is a cut view comparison of a continuously tilted tubing element forming a spiral conic coil and a twisted and variably tilted tubing element forming a spiral conic coil.

(34) FIG. 34 is a comparison of a helical heat exchanger and a conic spiral shaped heat exchanger.

DETAILED DESCRIPTION

(35) FIG. 1 shows the perspective view of a first embodiment of the tubing element 10. The tubing element 10 is a rigid elongated heat exchanger tube 10 having a first end 20 and a second end 30. The tubing element 10 is in a continuously tilted spiral shape.

(36) There are relatively large parallel opposite side walls 40 and 50 with generally flat surfaces. The opposite parallel arranged side walls 40, 50 of the tubing element are joined with relatively small opposite edge walls 45, 55, which are rounded connection walls 45, 55. The tubing element 10 is partially tilted and also helically wound and/or twisted so as to form at least a part of a conic spiral structure.

(37) The opening at ends 20 and 30 is varies in width and has the smallest opening distance near the connecting walls 45 and 55. The width of the opening between the first side wall 40 and the second side wall 50 is considerably smaller than the width of the side walls 40, 50.

(38) The opposite side walls 40 and 50 of the tubing element 10 are oppositely disposed in general parallel planes in the helix within the tube 10 there may be one or more media flow channels, which are formed between the oppositely disposed side walls 40, 50. The media flow channels are angularly disposed with respect to the axis. A heat transfer vapor or fluid such as water or oil or any refrigerant (liquid or vapor refrigerant) fills the tubing element 10 and flows from one end 20 of the tubing element 10 to the other end 30. Preferably, the resulting helix of the tubing element 10 is formed in a conic spiral coil (see e.g. FIG. 7 (continuously) and FIG. 9 (partial loop)).

(39) FIG. 2 shows the defining the radius 15 of the helix and an angle 1 defining the rise in the tubing element 10 coil. The radius 15 is progressively variable, meaning that the radius 14 decreases as the heat exchanger coil 100 progresses along its length.

(40) FIG. 3 shows the defining angles, i.e. angle defining the slope and angle defining the tilt. The twist of the tubing element 10 is determined merely by variables radius r, angle defining the slope and angle defining the tilt. Radius r defines the distance between the center of the tubing element 10 at the intersection of the central axis Z and the central transverse axis Y, both of the tubing element 10 and the central longitudinal axis X of the heat exchanger 100. Angle defines the slope of the tubing element 10 and extends between the central longitudinal axis X of the heat exchanger 100 and the central axis Z of the tubing element 10. Angle defines the tile of the tubing element 10 and extends between the central longitudinal axis Y of the heat exchanger 100 and the central transverse axis Y of the tubing element 10.

(41) The tubing element 10 is an elongated heat exchanger microchannel tube. The heat exchanger microchannel tube may be longitudinally curved around a central axis X into a conic spiral shape. This axis X is shown in FIG. 3 and is the central axis X of the overall and imaginary cylindrical shape of the conic spiral.

(42) FIG. 4 is a side elevation of a constantly tilted tube element that is tilted and twisted into a conic spiral coil of a heat exchanger 100. The single tubing element 10 is made of a heat transfer material, usually aluminum. This heat transfer material is rolled and formed into a sloped and tilted continuous conic spiral shape.

(43) Tube 10 has, as already discussed above, parallel side walls 40, 50 and the connecting walls 45, 55 which appear as curved edges. The tubing element is twisted to a desirable tilt and formed into the continuous conic spiral shape. The tube may have a plurality of adjacent small parallel internal channels with circular, angular, rectangular, square or more preferably circular cross sections (see e.g. FIG. 8).

(44) The heat transfer vapor or fluid flows through the channels and transfers heat through the tube bodies to the tube walls 40, 50 and edges 45, 55, from where heat is transferred between the walls and the surrounding medium or vice versa, such as e.g. already shown in FIG. 5, the walls 40, 50 may be scored, grooved or dimpled to increase the heat transfer surfaces.

(45) FIG. 5 is an isometric view of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(46) FIG. 6 shows a comparison of the side elevation and isometric views of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(47) FIG. 7 is a cut elevation view of a constantly tilted tube in a continuous loop forming a conic spiral coil.

(48) FIG. 8 is a perspective view of a tubing element with several alternatives for the internal structure of the tubing element. As can be seen in alternative A, only one channel may be provided which is defined by the side walls 40, 50 and the connecting walls 45, 55. As can be further derived from this detail A, the distance between the first side wall 40 and the second side wall 50 is considerably smaller than the width of the first side wall 40 and the second side wall 50 resulting in a substantially overall flat tubing structure of the tubing element 10. Exemplarily, the width of the first side wall 40 and the second side wall 50 is approximately at least ten times larger than the distance between the first side wall 40 and the second side wall 50.

(49) Furthermore, as shown in detail B, there may be also several microchannels 60 with a circular cross-section.

(50) Alternatively, as shown in detail C, there may be also several microchannels 70 with an angular cross-section, i.e. quadrangular cross-section.

(51) As shown in detail D, there may be also several microchannels 80 to a triangular cross-section.

(52) As shown in detail E, there may be several microchannels 90 with a quadrangular cross-section, which are arranged with an off-set to each other. In particular, as shown in detail F, all microchannels 90 are arranged with an off-set to each other forming a plurality of grooves 95 on the outer sides of the tubing element 10.

(53) FIG. 9 shows a half loop of a constantly tilted spiral tubing element 10.

(54) FIG. 10 shows a top view of a heat exchanger 100 formed by various interlaced constantly tilted tubing elements 10 that are arranged adjacent to each other.

(55) FIGS. 11-13 show various angles of the heating element 100 in a spiral conic shape.

(56) FIG. 14 is a comparison of a continuously tilted tubing element 10 and a cut view of a heating element 100 formed from continuously tilted tubing elements 10 in a conic spiral coil, with angle defining the tilt of the heating element coil 100. The diameter of the heating element coil 100 may vary. In some embodiments, the diameter at the top of the heating element 100 is larger than the diameter at the bottom of the coil. FIG. 16 shows two different heating elements 100 with the same upper diameter but different lower diameters. The tilt of the two heating elements 100 varies, as shown by the different between tilt angles and .

(57) FIG. 17 shows the perspective view of a second embodiment of the tubing element 130. The tubing element 130 is a rigid elongated heat exchanger tube, a first end 140 and a second end 150. The tubing element 130 is in a variably tilted spiral shape. The difference between this embodiment and the first embodiment (tubing element 10) is in the tilt angle of the heat exchange coil 100. In the first embodiment, tubing element 130 has a constant tilt angle. In the second embodiment, the tilt angle of tubing element 130 varies throughout the length of the heating element coil 200.

(58) FIG. 18 is a perspective view of tubing element shown in FIG. 17 showing the radii and angles for the of the tubing element 130, and FIG. 19 is a further perspective view of tubing element 130 shown in FIG. 17, showing the angles for the slope and the tilt of the tubing element.

(59) As in the first embodiment, there are relatively large parallel opposite side walls 160 and 170 with generally flat surfaces. The opposite parallel arranged side walls 160, 170 of the tubing element are joined with relatively small opposite edge walls 165, 175, which are rounded connection walls 165, 175. The tubing element 130 is partially tilted and also helically wound and/or twisted so as to form at least a part of a conic spiral structure.

(60) The opening at ends 140 and 150 is varies in width and has the smallest opening distance near the connecting walls 165 and 175. The width of the opening between the first side wall 160 and the second side wall 170 is considerably smaller than the width of the side walls 160, 170.

(61) FIGS. 20-23 show various angles of the heating element 100 in a spiral conic shape.

(62) FIG. 24 shows a half loop of a constantly tilted spiral tubing element 130, and FIG. 25 shows a top view of a heat exchanger 200 formed by various interlaced constantly tilted tubing elements 130 that are arranged adjacent to each other.

(63) FIGS. 26-29 show various angles of the heating element 200 that is formed by variable tilt element tubes 130 interlaced in a spiral conic shape.

(64) FIG. 30 is shows a cut view of a heating element 200 formed from variably tilted tubing elements 130 in a conic spiral coil, with angle defining the tilt of the heating element coil 100.

(65) FIG. 31 shows two different tubing elements 10 and 130 which have different tilt angles. Tubing element 10 is continuously tilted as and tubing element 130 has a variable tilt angle. This difference is seen from a top view of half loops of tubing elements 10 and 130 in FIG. 32 and a cut view of tubing elements 10 and 130 forming a heating element 100 and 200, respectively, in FIG. 33.

(66) FIG. 34 is a comparison of a helical heat exchanger 300, where in the top the spiral is formed as a cylinder around the longitudinal central axis along with fins 302 with covers 304 between the outer surfaces of adjacent tubes, and a conic spiral shaped heat exchanger 200. The heat conic spiral shaped heat exchanger 200 may offer a larger surface area than the helical heat exchanger and may also allow more balanced heat dissipation.

(67) While the invention has been described with reference to specific embodiments, modifications and variations of the invention may be constructed without departing from the scope of the invention, which is defined in the following claims.