INTERNALS IN A HELICALLY COILED HEAT EXCHANGER FOR SUPPRESSING GAS VORTICES

Abstract

The invention relates to a heat exchanger for indirect heat exchange between a first and second medium having: a shell, extending along a longitudinal axis and surrounding a shell space for receiving the first medium, and a plurality of tubes coiled helically onto a core tube which extends along the longitudinal axis in the shell space forming a tube bundle. The tube bundle comprises a number of tube layers lying one on top of the other in the radial direction. The second medium is conducted within the tubes to exchange heat indirectly with the first medium. The at least one distributor arm distributes a liquid phase of the first medium to an upper side of the tube bundle. The at least one distributor arm has, opposite from the upper side, a bottom with through-openings, so that the liquid phase can be passed to the upper side of the tube bundle. From an underside of the bottom of the at least one distributor arm, and at least one directing element projects in the direction of the upper side of the tube bundle and extends along the longitudinal axis toward the upper side of the tube bundle. The at least one directing element extends in a circumferential direction of the tube bundle over at least half the width of the bottom of the at least one distributor arm and/or the at least one directing element projects along the longitudinal axis into a gap of the tube bundle arranged between two tube layers of the tube bundle.

Claims

1. Heat exchanger (1) for indirect heat exchange between a first and a second medium (M, M), having: a shell (5), which is made to extend along a longitudinal axis (z) and surrounds a shell space (6), which serves for receiving the first medium (M), a plurality of tubes (30), which are in each case coiled helically onto a core tube (300) of the heat exchanger (1), which extends along the longitudinal axis (z) in the shell space (6), so that the tubes (30) form a bundle of tubes (3) of the heat exchanger (1) which is arranged in the shell space and comprises a number of tube layers (4) lying one on top of the other in the radial direction (R) of the bundle of tubes (3), the second medium (M) being able to be conducted through at least one tube (30) of the bundle of tubes (3), so that heat is exchangeable indirectly between the first medium (M) and the second medium (M), and at least one distributor arm (21) for distributing a liquid phase (F) of the first medium (M) to an upper side (3a) of the bundle of tubes (3) facing the at least one distributor arm (21), the at least one distributor arm (21) having opposite from the upper side (3a) a bottom (200) with through-openings (205), so that the liquid phase (F) can be passed to the upper side (3a) of the bundle of tubes (3) by way of the through-openings (205), characterized in that, from an underside (200a) of the bottom (200) of the at least one distributor arm (21) that is facing the upper side (3a) of the bundle of tubes (3), at least one directing element (22) projects in the direction of the upper side (3a) of the bundle of tubes (3), the at least one directing element (22) extending in a circumferential direction (U) of the bundle of tubes (3) at least over half of the respective width (B) of the bottom (200) of the at least one distributor arm (21) and/or the at least one directing element (22) projecting along the longitudinal axis (z) into a gap (31) of the bundle of tubes (3) that is arranged between two tube layers (32) of the bundle of tubes (3).

2. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) is formed so as to prevent a cross flow of the gaseous and/or liquid phase (F) of the first medium (M) on the upper side (3a) of the bundle of tubes (3).

3. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) is formed as a directing plate (22).

4. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) extends along the circumferential direction (U) of the bundle of tubes.

5. Heat exchanger according to claim 1, characterized in that the at least one distributor arm (21) has two side walls (203, 204), which lie opposite one another in the circumferential direction (U) of the bundle of tubes (3), extend in each case along the radial direction (R) of the bundle of tubes (3), the at least one directing element (22) extending in the circumferential direction (U) of the shell (5) from one side wall (203) to the other side wall (204).

6. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) has in a plane running perpendicularly to the longitudinal axis (z) a curvature, in particular a curvature with a constant radius of curvature (R).

7. Heat exchanger according to claim 1, characterized in that the heat exchanger (1) has a number of directing elements (22), which project in each case from an underside (200a) of the bottom (200) of the at least one distributor arm (21) that is facing the upper side (3a) of the bundle of tubes (3) in the direction of the upper side (3a) of the bundle of tubes (3), the directing elements (22) in each case extending in a circumferential direction (U) of the bundle of tubes (3) at least over half of the respective width (B) of the bottom (200) of the at least one distributor arm (21) and/or the at least one directing element (22) in each case projecting along the longitudinal axis (z) into a gap (31) of the bundle of tubes (3) that is arranged between two tube layers (32) of the bundle of tubes (3).

8. Heat exchanger according to claim 1, characterized in that the directing elements (22) are arranged next to one another in a radial direction (R), along which the at least one distributor arm (21) extends from the core tube (300) toward the shell (5).

9. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) forms a channel (22) that extends in the direction of the longitudinal axis (z), with a wall (220), the channel (22) being in flow connection with at least one through-opening (205) of the bottom (200).

10. Heat exchanger according to claim 9, characterized in that the channel (22) is formed by a tube (22) with in particular a circular cross section.

11. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) forms a plurality of channels (22a) that extend in the direction of the longitudinal axis (z) and have respective walls (22b), neighboring channels (22a) forming common walls (22b) or the walls (22b) of neighboring channels (22a) being adjacent to one another, the respective wall (22b) bounding a region (B) of the shell space (6) between the bottom (200) of the at least one distributor arm (21) and the upper side (3a) of the bundle of tubes (3) into which at least one through-opening (205) of the bottom (200) of the at least one distributor arm (21) opens out.

12. Heat exchanger according to claim 11, characterized in that the channels (22a) are formed in cross section in an n-gonal manner, n being greater than or equal to 3, and in particular n being equal to 4 or equal to 6.

13. Heat exchanger according to claim 1, characterized in that the at least one directing element (22) is formed by a wall (22) which extends along a periphery (200b) of the bottom (200) and surrounds a region (B) of the shell space (6) between the bottom (200) of the at least one distributor arm (21) and the upper side (3a) of the bundle of tubes (3) into which the through-openings (205) of the bottom (200) of the at least one distributor arm (21) open out.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Further details and advantages of the invention are to be explained by the following description of the figures of an exemplary embodiment by reference to the figures, in which:

[0038] FIG. 1 shows a schematic sectional representation of a heat exchanger according to the invention with directing elements in the form of directing plates, which project from an underside of the bottom of a distributor arm of the heat exchanger;

[0039] FIG. 2 shows a schematic plan view of the underside of the bottom of the heat exchanger shown in FIG. 1;

[0040] FIG. 3 shows a perspective, partially sectional view of the heat exchanger according to the invention of the type from FIGS. 1 and 2;

[0041] FIG. 4 shows a schematic plan view of the underside of a bottom of a heat exchanger according to the invention from which a honeycomb-shaped directing element projects;

[0042] FIG. 5 shows a schematic plan view of the underside of a bottom of a heat exchanger according to the invention from which a directing element with rectangular cells projects;

[0043] FIG. 6 shows a schematic plan view of the underside of a bottom of a heat exchanger according to the invention from which a directing element with a wall running along the bottom projects;

[0044] FIG. 7 shows a schematic sectional view of the heat exchanger shown in FIG. 6;

[0045] FIG. 8 shows a schematic plan view of the underside of a bottom of a heat exchanger according to the invention from which tubular directing elements project; and

[0046] FIG. 9 shows a schematic sectional view of the heat exchanger shown in FIG. 8.

[0047] FIG. 1 shows in conjunction with FIGS. 2 and 3 an embodiment of a heat exchanger according to the invention for indirect heat exchange between a first and a second medium M, M. The heat exchanger 1 has a shell 5, which is made to extend along a longitudinal axis z and surrounds a shell space 6, which serves for receiving the first medium M, and also a plurality of tubes 30, which are in each case coiled helically onto a core tube 300 of the heat exchanger 1, which extends along the longitudinal axis z in the shell space 6, so that the tubes 30 form a bundle of tubes 3 of the heat exchanger 1 which is arranged in the shell space 6 and comprises a number of tube layers 32 lying one on top of the other in the radial direction R of the bundle of tubes 3, the second medium M being conducted in the bundle of tubes 3, so that heat is exchangeable indirectly between the first medium M and the second medium M. The second medium M can be introduced into the bundle of tubes 3 in particular through at least one nozzle provided on the shell 5 (not shown in FIG. 3) and can be drawn off from the bundle of tubes 3 by way of at least one nozzle 4 provided on the shell 5. The bundle of tubes 3 may also be surrounded by a jacket 7, which serves for reducing a bypass flow in the shell space 6 (past the bundle of tubes 3).

[0048] The heat exchanger 1 also has at least one distributor arm 21, preferably a number of distributor arms 21, which serve(s) for distributing a liquid phase F of the first medium M to an upper side 3a of the bundle of tubes 3 facing the respective distributor arm 21, the respective distributor arm 21 having opposite from the upper side 3a a bottom 200 with through-openings 205, so that the liquid phase F can be passed to the upper side 3a of the bundle of tubes 3 by way of the through-openings 205. As a difference from FIG. 3, for the sake of simplicity FIGS. 2, 4, 5, 6 and 8 only show one distributor arm 21 in each case.

[0049] The respective distributor arm 21 projects in particular in a radial direction R, which is disposed perpendicularly on the longitudinal axis z, from the core tube 300 and is preferably in flow connection with it. The core tube 300 in turn projects from a pre-distributor 20, which is arranged above the bundle of tubes 3 and the distributor arms 21 and in which the first medium M is collected and in particular degassed. The liquid phase F can correspondingly flow from the pre-distributor 20 into the core tube 300 and subsequently into the respective distributor arm 21. Instead of the core tube 100, the liquid phase F may also be fed into the respective distributor arm 21 by way of an annular channel, which for example runs around the inside of the shell 5. Then, from an underside 200a of the bottom 200 of the respective distributor arm 21 that is facing the upper side 3a of the bundle of tubes 3, at least one directing element 22 projects in the direction of the upper side 3a of the bundle of tubes 3 and thereby extends in each case along the longitudinal axis z toward the upper side 3a of the bundle of tubes 3. Preferably, the at least one directing element 22 extends in a circumferential direction U of the bundle of tubes 3 at least over half of the width B of the bottom 200 of the at least one distributor arm 21 (cf. FIG. 2).

[0050] According to the embodiment shown in FIGS. 1 to 3, a number of such directing elements 22 are provided, formed in each case as a directing plate. The respective directing plate 22 is in this case connected by way of an upper peripheral region 221with respect to the vertically aligned longitudinal axis zto the underside 200a of the bottom 200 of the respective distributor arm 22, an opposite lower peripheral region 222 of the respective directing plate 22 ending at the upper side 3a of the bundle of tubes 3 or,as shown in FIG. 1, in each case projecting into a gap 31 between two tube layers 32 lying one on top of the other in the radial direction R. As already mentioned above, this may be a gap 31 between neighboring tube layers 32 or some other depression/gap between two tube layers 32, for example a gap above a tube layer which lies at a lower level in comparison with the two tube layers adjacent on both sides, therefore represents a gap. Preferably, mechanical contact between the respective directing element 22 and the bundle of tubes 3 is avoided, in order to reduce the risk of leakage of the bundle of tubes 3.

[0051] The directing elements or plates 22 are preferably arranged next to one another in the radial direction R, along which the respective distributor arm 21 extends from the core tube 300 toward the shell 5, one or more of the through-openings 205 in each case opening out into an intermediate space between two directing plates 22 that are neighboring in the radial direction R, so that the liquid phase F can be discharged into the respective intermediate space above the upper side 3a of the bundle of tubes 3.

[0052] The directing elements 22 configured in such a way serve in this case for preventing a cross flow of the gaseous phase G of the first medium M on or along the upper side 3a of the bundle of tubes 3 or along the radial direction R. As a result, the liquid phase F can be discharged undisturbed by way of the distributor arms 21 along the longitudinal axis z in the downward direction, and an uneven distribution of the liquid phase F is prevented.

[0053] As can be seen from FIGS. 1 to 3, the respective directing plate 22 preferably extends along a circumferential direction U of the bundle of tubes 3 or the shell 5 and in this case preferably has a curved path (in particular with a radius of curvature R), so that a concavely curved side of the respective directing plate 22 is facing the core tube 300, whereas the respective convexly curved side is facing the shell 5 in the outward direction.

[0054] The respective distributor 21 has furthermore two side walls 203, 204, which lie opposite one another in the circumferential direction U of the bundle of tubes 3 or the shell 5, extend in each case along the radial direction R of the bundle of tubes 3 from the inside to the outside toward the shell 5 of the heat exchanger 1 and in each case project upward along the longitudinal axis z from a periphery 200b of the bottom 200 of the respective distributor arm 21.

[0055] The respective distributor arm 21 has furthermore an end-face wall 201, which lies opposite the shell 5 in the radial direction R and connects the two side walls 203, 204 to one another. In the upward direction, the respective distributor arm 21 is preferably closed by a roof 206, which is connected to the respective side walls 203, 204 and the end-face wall 201 and slopes up toward the core tube 300, so that the gaseous phase G of the first medium M can rise up along the ridge 206 to the core tube 300.

[0056] It is preferably also provided (cf. in particular FIG. 2) that the respective directing element 22 extends on the underside 200a of the bottom 200 of the respective distributor arm 21 in the circumferential direction U from the one side wall 203 to the other side wall 204 (that is to say over an entire width B of the bottom 200 in the circumferential direction U, it being possible for the width B of the bottom 200 to vary in the radial direction R, in particular in the case of a bottom 200 in the form of a sector of a circle).

[0057] Between every two distributor arms 21 that are neighboring in the circumferential direction U of the shell 5 there is a gap through which a tube cluster 33 of the bundle of tubes 3, formed by end portions of the tubes 3, is in each case led past the distributor arms 21 to an assigned tubesheet 34, which in each case is fixed on the shell 5.

[0058] FIG. 4 shows a further embodiment of the present invention, in which a contiguous directing element 22 in each case extends from the underside 200a of the bottom 200 of the respective distributor arm 21 in the direction of the upper side 3a of the bundle of tubes 3. The respective directing element 22 forms a plurality of channels 22a, which in each case extend along the longitudinal axis z, the respective channel 22a being surrounded by a running-around wall 22b and in each case bounding a region B of the shell space 6 between the bottom 200 of the at least one distributor arm 21 and the upper side 3a of the bundle of tubes 3 into which at least one through-opening 205 of the bottom 200 of the at least one distributor 21 opens out.

[0059] The individual running-around walls 22b are formed in particular hexagonally in cross section (with respect to a cross-sectional plane made to extend parallel to the respective bottom 200) and are connected in each case to neighboring walls 22b, so that the respective directing element 22 forms overall a honeycomb structure, as can be seen from FIG. 4. The individual channels 22a therefore share their respective running-around wall 22b with the neighboring channels 22a.

[0060] FIG. 5 shows a modification of the directing element 22 shown in FIG. 4, here, as a difference from FIG. 4, the individual channels 22a having a rectangular shape with respect to the cross-sectional plane defined above. In FIGS. 4 and 5, the channels 22a may deviate from the hexagonal or rectangular shaping at the periphery 200b of the underside 200a of the respective bottom 200 (in particular because of the configuration of the bottoms 200 of the distributor arms 21 preferably in the form of sectors of a circle).

[0061] FIG. 6 shows in conjunction with FIG. 7 a further embodiment of a directing element 22 according to the invention, in which the at least one directing element 22 is formed by a wall 22, which extends along an outer periphery 200b of the bottom 200 and projects from the underside 200a of the bottom 200 of the assigned distributor arm 21 in the direction of the upper side 3a of the bundle of tubes 3. The wall or the directing element 22 has here a first portion 22c, which extends in the radial direction R from the core tube 300 outward to the end-face wall 201 of the assigned distributor arm 21. From there, a second portion 22d of the wall 22 that is connected to the first portion 22c of the wall 22 extends in the circumferential direction U to the opposite portion of the periphery 200b of the bottom 200 and is connected there to a third portion 22e of the wall 22, the third portion 22e of the wall 22 extending along the radial direction R back to the core tube 300. The directing element 22 consequently surrounds a region B of the shell space 6 between the bottom 200 of the assigned distributor and 21 and the upper side 3a of the bundle of tubes 3 into which the through-opening 205 of the bottom 200 of the respective distributor arm 21 opens out. In this case, the individual portions 22c, 22d, 22e of the wall 22 in particular are connected by way of an upper peripheral region 221 to the underside 200a of the respective bottom 200, whereas the respectively opposite lower peripheral region 222 runs along the upper side 3a of the bundle of tubes 3. In this case, the respectively opposite lower peripheral region 222 may also project by a certain portion into one or more gaps of the tube bundle 3.

[0062] According to a further embodiment, shown in FIGS. 8 and 9, it is provided that the respective distributor arm 21 has a number of directing elements 22, which are configured here in each case as a channel 22 with a running-around wall 220, it being possible for the respective channel 22 to be formed by a tube 22 with in particular a circular cross section, the respective tube 22 or the respective channel 22 projecting from the underside 200a of the bottom 200 of the respective distributor arm 21. In this case, the through-openings 205 of the bottom 200 of the respective distributor arm 21 open out in each case into one of the tubes 22. The tubes 22 extend in each case along the longitudinal axis z downward to the upper side 3a of the bundle of tubes 3 and end at the upper side 3a or project in each case with one end into a gap of the tube bundle 3, for example a gap 31 that is present between two tube layers 32.

TABLE-US-00001 List of reference numerals 1 Heat exchanger or latent heat exchanger 3 Bundle of tubes 3a Upper side 4 Nozzle 5 Shell 6 Shell space 7 Jacket 10 Web 20 Pre-distributor 22 Directing elements, wall 22a Channel 22b Wall 22c, 22d, 22e Portion 30 Tubes 31 Gap 32 Tube layer 33 Tube cluster 34 Tubesheet 200 Bottom 200a Underside 200b Periphery 201 End-face wall 203, 204 Side wall 205 Through-opening 206 Roof 220 Wall 221 Upper peripheral region 222 Lower peripheral region 300 Core tube M First medium M Second medium R Radial direction U Circumferential direction z Longitudinal axis B Width B Region R Radius of curvature