WO2009010834A1

WO2009010834A1 - Heat exchanger

Info

Publication number: WO2009010834A1
Application number: PCT/IB2008/001457
Authority: WO
Inventors: Veronika Bognarne Fejes
Original assignee: WTS Kereskedelmi és Szolgáltató Kft.
Priority date: 2007-07-17
Filing date: 2008-06-02
Publication date: 2009-01-22
Also published as: ES2355016T3; HK1146648A1; EP2165143A1; DK2165143T3; ZA201000973B; DE502008001668D1; CN101796364A; DE102007033166A1; PL2165143T3; ATE486259T1; EP2165143B1; PT2165143E; SI2165143T1; CN101796364B; UA97285C2; US20100181045A1

Abstract

The invention relates to a heat exchanger (10) having an elongate hollow body with connections (12, 12', 13, 13') for the supply and discharge of a first and of a second medium, in which the first medium is guided through the elongate hollow body in a counterflow with respect to a second medium, and the second medium flows through a spiral tube (11) which extends longitudinally axially between the end sides of the hollow body, and wherein a plurality of deflecting elements (18) projects into the hollow body interior from the hollow body inner casing, which deflecting elements deflect the flow of the first medium. To improve efficiency, it is provided that the deflecting elements project in an alternating sequence from in each case opposite hollow body sides into the hollow body interior and into the region of the spiral tube, in such a way that said deflecting elements end between two spirals, and that the hollow body inner casing has, in sections, a plurality of concavely-shaped constrictions.

Description

heat exchangers

The invention relates to a heat exchanger, in particular for swimming pools with an elongated hollow body with connections to the inlet and outlet of a first and a second medium, in which the first medium is passed in countercurrent or direct current to a second medium through the elongated hollow body and the second medium flows through helical tube, which extends longitudinally axially between the end faces of the hollow body, and in which project from the inner hollow body shell a plurality of deflection in the hollow body interior, which deflect the flow of the first medium.

Pool heat exchangers are used to heat the bath water as a first medium by means of a heating medium as a second medium. Typically, this heat exchangers are used, which consists essentially of a large pipe for bathing water and a heating coil laid therein for a heating medium. As it flows through the two media in their associated pipes, the bath water absorbs the heat from the heating means, which consequently becomes cooler. The heating coil can take any forms within the heat exchanger. The effectiveness of conventional heat exchangers depends inter alia on how large the surface of the heating coil is within the heat exchanger. The larger the surface of the heating coil, the more effective the heat exchanger works. Usually, the heating coil is laid helically within the heat exchanger to increase the surface area. In heat exchangers of the type described above, the medium to be heated flows centrally through the spiral heating coil or the medium flows around the heating spiral on the outside. The same principle is also used in instantaneous water heaters in which the heating coil is an electrically heated heating coil. The difference to a heat exchanger in that in a water heater much more heat is delivered to the water flowing through. All named in the description and in the claims embodiments of the heat exchanger according to the invention are in principle transferable to a water heater of the same type. Such a heat exchanger is described for example in DE 100 51 756 B4. A heating medium is passed through vertically attached to the heat exchanger housing feed lines in the heat exchanger housing and flows through the heating coil. At the same bath water is guided longitudinally in the heat exchanger, thereby flows around the heating coil and consequently absorbs heat. The flow directions of both media through the heat exchanger are chosen in opposite directions.

No. 5,309,987 describes a heat exchanger with baffle plates, which, except for a few openings, extend in a circular manner over the inner jacket of a cylindrical housing and which are intended to produce a turbulent flow of the medium flowing through. Due to the oblique arrangement of the baffles to the housing longitudinal axis there is the danger that due to occurring turbulence in individual areas accumulation zones arise, from which the used first medium flows only insufficient, so that it can only come to an insufficient heat transfer.

US Pat. No. 1,893,484 describes a heat exchanger which has a cylindrical housing, on the inner shell of which helically arranged guide vanes are provided. By this spiral-like arrangement of the guide vane, in contrast to the central region of the housing interior, in which the helical tube is arranged, a significantly larger laminar flow is generated, so that there is a risk that the first medium accumulates in the region of the helical tube and does not flow off ,

It is an object of the present invention to improve known heat exchanger such that the energy efficiency is optimized, the design of the heat exchanger should still be compact and space-saving.

This object is achieved by the heat exchanger according to claim 1, which is characterized in that the deflecting elements in alternating sequence of each opposite hollow body sides in the hollow body interior to the Area of the helical tube protrude so that they end between two coils and that the hollow body inner shell has a plurality of concave constrictions in sections.

Further developments of the invention are described in the subclaims.

The heat exchanger according to the invention is particularly intended to heat pool water, but it can also heat other liquids. For example, the heat exchanger could be used to heat aquarium water. The heat exchanger according to the invention is in principle also suitable for use as a cold exchanger.

The effect of the heat exchanger according to the invention consists in particular in that the existing deflecting direct the hot water to be heated in the direction of the helical tube. Furthermore, the flow rate of the first medium (service water) should be controlled so that along the helical pipe snake a longer residence time and thus a greater heat transfer is achieved.

The inflowing first medium is selectively guided by the deflecting between the helical tubes, wherein in the region of the constriction of the elongated hollow body, a flow acceleration and in the extension regions lying between the constrictions of the hollow body interior pressure relaxations and thus lower flow velocities are generated.

According to a particular embodiment of the invention, the elongated hollow body in cross-section oval or elongated round, wherein the deflecting elements are preferably arranged on the narrow sides of the oval. This measure also optimizes both the residence time of the first medium in the area of helical coils and the stability of the heat exchanger housing. Further preferably, two to three 360 ° turns of the helical tube are arranged between two adjacent deflection elements. It has been found that this optimization creates the greatest possible heat transfer between the helical tube and the first medium. For the same purpose, the design of the helical tube serves as a corrugated tube, which has a larger surface area in contrast to a smooth-walled tube.

The hollow body inner shell has a smooth surface, whereby deposits and unwanted turbulence of the first medium flowing past there are avoided.

Furthermore, in order to optimize the flow flow of the first medium, the deflection elements are flat bodies with a preferably concavely curved inner edge.

Both for manufacturing reasons and to prevent the unwanted heat dissipation of the housing to the outside environment, the elongated hollow body, preferably including the deflecting elements made of plastic, in particular polyamide. The plastic housing can be produced in particular by injection molding.

In a further embodiment of the invention, the elongated hollow body consists of several, one another plug-in pieces of pipe which are detachably connected to each other. In this way, a modular heat exchanger is created, which consists of any number of individual pieces of heat-resistant and especially corrosion-resistant plastic with high insulation and high security against calcification.

To attach the elongated hollow body to a wall, its housing has on its outer jacket protruding tabs with an opening for the passage of a fastening screw. Further preferably, a bracket is provided for fastening the elongated hollow body to a wall, the ends of which are bent by 180 ° and viewed in a plan view arranged congruently arranged bores for the passage of a bolt or screw shank.

The 180 ° bend of the strap ends makes it possible to tighten the bolt or the screw in such a way that a compressive stress is built up in the U-shaped bent part, which loosens the screw connection from the outset.

According to a further embodiment of the invention, the bracket has a concave-shaped central portion, which preferably has the same curvature profile as the elongated hollow body present there.

According to a further embodiment, the deflecting elements are individual wall pieces either vertically or inclined by 2 ° to 3 ° relative to the vertical, projecting into the interior of the housing. With an inclination relative to the vertical, the angle between the direction of flow of the first medium and the deflecting elements is thus approximately 88 °.

Furthermore, the deflecting elements protrude in alternating sequence from respective opposite sides of the hollow body interior by an edge dimension of 1/3 to 1/7, preferably 1/5 of the inner diameter of the hollow body in the hollow body interior.

The hollow body inner casing has at least partially a wave-shaped profile in the direction of the longitudinal axis, the constrictions of the diameter preferably amounting to 5% to 10% of the interior of the hollow body. The connections for the first and second medium are arranged end-to-end in a preferred embodiment.

The heat exchanger consists of several individual elements, whereby the length of the heat exchanger can be selected arbitrarily, since any number of elements can be interconnected. are bindable. Each of the elements has a fastening tab, so that even larger heat exchanger housing can be securely fixed. The attachment of the heat exchanger can be selected both on an existing masonry, ie a wall or as a suspension on a ceiling as well as for attachment to a pallet for integration within a system. If one uses the heat exchanger for swimming pool water heating, the heating can be done both by heating water and by solar heat. The heating medium as the second medium is guided through a rib-shaped helical tube. This helical tube serves as Heizwasserrohr, which is flowed vertically and horizontally from the first medium in the heat exchanger, so that a uniform heat extraction is possible. The convex-concave design of the heat exchanger housing with internal deflection elements extends the residence time of the first medium in the heat exchanger housing, which ensures greater heat transfer. The heating medium can be cooled more, which results in a lower heat loss on the return path and thus a saving of heating energy. The helical Heizwasserrippenrohre are preferably made of highly corrosion-resistant and pressure-resistant stainless steel and screwed to the front side with a double nipple.

The preferably selected deflecting elements protrude by 20mm to 30mm, preferably 25mm long in the hollow body inside, namely at an angle of 90 ° or slightly opposite the direction of flow by 2 ° to 3 ° inclined into the heat exchanger inside. The deflection elements are circular segment-like and have a concave upper edge, which, however, can also be shaped differently. By the deflection elements which are mounted alternately on opposite sides of the heat exchanger interior, the medium to be heated is passed several times to the centrally arranged heating coil, the helical tube. Due to this special construction of the deflecting elements, the flow direction of the first medium to be heated is constantly changed, so that it is guided past the helical heating coil in an improved manner in a countercurrent principle. The successive constrictions and expansions in the housing interior also cause an alternating compression and relaxation of the flowing first medium with the result that the residence time of the first medium in the area of the heating coil increases and thus the heat output is improved.

The oval shape of the heat exchanger allows high internal stresses without material stresses. The deflection elements, which are integrated on the narrow sides, also improve the statics of the heat exchanger housing.

Further embodiments of the invention are described below with reference to the drawings. Show it

1 a shows a longitudinal axial section through the heat exchanger with integrated helical heating coil,

1b is a cross-axial section through the heat exchanger,

1c shows a longitudinal axial section through the heat exchanger with a possible flow path,

1d shows a longitudinal axial section through the heat exchanger with a further possible flow path,

2a a heat exchanger without center piece,

2b shows a heat exchanger with a center piece,

2c shows a heat exchanger with two middle pieces,

FIG. 3 is a cross-axial section with fastening device in an exploded view,

4 shows a longitudinal axial section through a water heater, Fig. 5 is a transverse axial section through a heat exchanger.

Fig. 1a shows a heat exchanger 10 with an integrated helical tube 11 as a heating coil. In the present case, hot water is provided as the heating medium, which is passed through the helical pipe. Alternatively, however, it is also possible to form the helical tube as a heated with electric current heating coil (immersion heater principle). The helical tube 11 may have a smooth surface, but preferably it is configured as a corrugated tube. The helical tube 11 is fixed by means of a double nipple 13, 13 'each end side on the heat exchanger housing.

The illustrated water connections 12, 12 'in the form of a flange bushing and a union nut, which are preferably made of ABS, serve to supply and drain the first medium, which is to be heated. Preferably, the first and second medium flow in opposite directions. The heat exchanger 10 has a cross-sectionally oval housing. The direction of flow of the first medium is represented by the arrow 14 and the direction of flow of the second medium by the arrow 15. In the present case, the heat exchanger has two end pieces 16, 16 'and two center pieces 17, 17', which are assembled together with the end pieces to form a heat exchanger 10. The end pieces and the center pieces 16, 16 ', 17, 17' are each plugged together, with adjacent parts being fixed via a connection consisting of bolts and screws. For this purpose, have the end and intermediate pieces 16, 16 'each outer side tabs with holes through which a bolt or a screw shaft can be inserted therethrough.

In principle, the number of centerpieces 17, 17 'freely selectable.

On the inner jacket, the middle pieces 17, 17 'deflecting elements 18 which project vertically into the hollow body interior. Alternatively, instead of the vertical alignment, it is also possible to select an orientation that is tilted slightly by 2 ° to 3 ° relative to the flow direction 14. The deflecting element 18 is located in the direction of flow 14 in the region in which the inner diameter tapers. In flow seen direction lies on the opposite hollow body inside jacket side at a distance a second deflecting 18. The deflecting elements protrude so far into the heat exchanger housing inside that they end in the region of the helical tube 11. Between two adjacent deflection elements arranged on opposite sides are two to three turns of the helical tube 11.

The respective abutting lips 101 of the end and middle pieces are sealed via an O-ring 102, which rests in a groove.

FIG. 1b shows in detail that the heat exchanger 10 has an oval cross-sectional shape. At the periphery of the housing, the screw and nut connections 103 can be seen.

Figures 1c and d show flowlines 104, 106 which can be adjusted at different pressures and flow rates of the inflowing first medium. In any case, it can be seen that the inflowing first medium, in particular swimming pool water, strikes against the deflecting elements 18 and from there is directed in the direction of the helical pipes, but the flow in each case undergoes a reversal of direction and is returned in a loop-shaped movement, where it rises new inflowing water hits. Depending on the set pressure, the respective deflections or Verwirbellungen, which are marked in Fig. 1c with 105, larger or smaller. It is essential that with extended dwell the heating coil, d. H. the helical tube 11 is flowed through not only simply but several times by the first medium to be heated, in particular swimming pool water.

2a to c show the heat exchangers 20, 20 ', 20' according to the invention in different lengths, which are produced by connecting two end pieces directly to one another or via one or two or more middle pieces, depending on the number of inserted center pieces between two Endstü- The length of the heat exchanger can be varied as desired and adapted to the desired conditions.

Fig. 3 shows an exploded view of the attachment of the heat exchanger housing to a wall 32. The heat exchanger 30 has this on its outer jacket protruding tabs 301 with an opening, such as a hole or a slot for the passage of a fixing screw 31. To prevent the heat exchanger gradually from the attachment, caused by vibrations in the heat exchanger operation, solves a bracket 32 is provided, which is bent at its ends 33, 34 by 180 °. The bracket 32 consists of a thin-walled sheet, which has two congruently lying holes in the region of 180 ° -Umbiegungen through which the shank of the screw 31 can be passed. This screw also engages in dowels 35 which are anchored in the wall 32.

If the screw 31 is tightened, finally, a pressure is exerted on the U-profile of the bracket at its ends 33, 34, which after fixing the screw 31 permanently acts on the screw head, the rotation of which is hindered. In addition, a lock nut 36 and a washer 37 (each per screw) can be used as further anti-rotation.

The bracket 32 has a concave shaped central portion 38 whose shape is adapted to the outer contour or the respective radius of curvature of the heat exchanger.

The system is designed so that both externally heated media and electrical heating coils can be installed, which can also be operated with solar heat. In Fig. 4, a water heater 41 is shown, which has electrically heated heating coils 42 which are mounted on the left housing part. The illustrated embodiment comprises only one central element in which two deflecting elements are arranged. Due to the front side arranged power connection, the water connection 44 is not frontally, but laterally at the Durch- Iauferhitzer41 arranged. Furthermore, a possible circular flow pattern 45 of the water to be heated is shown. Of course, a wave-shaped flow course is also conceivable, as shown for example in FIG. 1 c.

Fig. 5 shows an exemplary embodiment of the deflecting elements 18, which are shown hatched. The deflecting elements form a segment which extends from the jacket of the heat exchanger inwards. From the lowest point, the height of the deflection element relative to the largest (here vertically arranged) diameter of the heat exchanger is between 1/5 and%. The upper edge of the deflecting elements 18 is concave.

Claims

claims

1. heat exchanger (10), in particular for swimming pools, with an elongated hollow body with connections to the inlet and outlet of a first and a second medium, in which the first medium is passed in countercurrent or direct current to a second medium through the elongated hollow body and the second Medium flows through a helical tube (11) that extends longitudinally axially between the end faces of the hollow body and wherein from the hollow body inner shell several deflecting elements (18) protrude into the hollow body interior, which deflect the flow of the first medium, characterized in that the deflecting elements (18) in alternating Sequence of respectively opposite hollow body sides in the hollow body interior into the region of the helical tube (11) protrude so that they end between two coils and that the hollow body inner shell has a plurality of concave constrictions (17) in sections.

2. Heat exchanger according to claim 1, characterized in that the elongated hollow body in cross-section oval or oblong-round is formed, wherein the deflecting elements (18) are preferably arranged on the narrow sides of the oval.

3. Heat exchanger according to claim 1 or 2, characterized in that between two adjacent deflecting elements (18) two to three 360 ° -Windun- conditions of the helical tube (11) are arranged.

4. Heat exchanger according to one of claims 1 to 3, characterized in that the helical tube (11) is a corrugated tube.

5. Heat exchanger according to one of claims 1 to 4, characterized in that the hollow body inner shell has a smooth surface.

6. Heat exchanger according to one of claims 1 to 5, characterized in that the deflecting elements (18) are flat body, which preferably have a concave inner edge.

7. Heat exchanger according to one of claims 1 to 6, characterized in that the elongated hollow body, preferably including the deflecting elements, made of plastic, in particular polyamide.

8. Heat exchanger according to claim 7, characterized in that the elongated hollow body consists of a plurality of plug-in pipe sections which are detachably connected to each other.

9. Heat exchanger according to one of claims 1 to 8, characterized in that the elongated hollow body at its outer jacket protruding tabs (301) having an opening for the passage of a fastening screw (31).

10. Heat exchanger according to claim 9, characterized in that for fastening the elongated hollow body to a wall (32), a bracket (39) is provided, whose ends (33, 34) are bent over by 180 ° and viewed in a plan view arranged congruent Have holes for the passage of a bolt or screw shank.

11. A heat exchanger according to claim 10, characterized in that the bracket (39) has a concave shaped central portion (38), which preferably has the same radius of curvature or curvature as the elongated hollow body (30).

12. Heat exchanger according to one of claims 1 to 11, characterized in that the deflection elements (18) from individual vertically or by 2 ° to 3 ° relative to the vertical inclined into the hollow body interior projecting wall pieces.

13. Heat exchanger according to claim 12, characterized in that the deflecting elements protrude in alternating sequence of respective opposite sides in the hollow body interior, preferably by an edge dimension of 1/3 to 1/7, further preferably 1/5, of the inner diameter of the hollow body.

14. Heat exchanger according to one of claims 1 to 13, characterized in that the hollow body inner casing in the direction of the longitudinal axis at least partially has a wavy profile, wherein the constrictions of the diameter preferably amount to 5% to 10% of the housing interior.

15. Heat exchanger according to one of claims 1 to 14, characterized in that the connections for the first and second medium are arranged frontally.

16. Heat exchanger according to one of claims 1 to 15, characterized in that the helical tube (11) is an electrically heated heating coil.

17. Heat exchanger according to one of claims 1 to 16, characterized in that the heat exchanger is designed as a water heater.