WO2011101106A2

WO2011101106A2 - Heat exchanger

Info

Publication number: WO2011101106A2
Application number: PCT/EP2011/000640
Authority: WO
Inventors: Ott Erwin
Original assignee: opk Kälte- und Klimatechnik AG
Priority date: 2010-02-18
Filing date: 2011-02-11
Publication date: 2011-08-25
Also published as: WO2011101106A3; EP2536991A2; DE102010008533A1

Abstract

The invention relates to a heat exchanger (10) for heat transfer between a gaseous medium and a second gaseous or liquid medium, comprising a heat exchanger housing (11) in which a tube bundle (13) is arranged that is guided through a lamellar arrangement (12), the lamellae (23) being connected to the tubes (15) in a thermally conductive manner. According to the invention, a gas flow region (16) is provided around the lamellar arrangement (12) between at least two connections (17, 18) for the gaseous medium and at least two connections (21, 22) for supplying and discharging the second gaseous medium or liquid medium to and from the tube bundle (13).

Description

heat exchangers

Description :

The invention relates to a heat exchanger, in particular a

Suction gas heat exchanger, for heat transfer between a liquid medium and a gaseous medium, with a

Heat exchanger housing, in which a tube bundle is arranged.

Such heat exchangers are used in refrigeration and can be in particular elements of refrigeration circuits of refrigerators, heat pumps or ORC processes. In the known

Heat exchangers are passed through the tube bundle, the gaseous refrigerant, while the liquid refrigerant flows through the space between the tube bundles and the inner wall of the housing of the heat exchanger. If the heat transfer performance of the heat exchanger to be increased, so the entire arrangement

Extends heat exchanger housing and tube bundles and / or the

Diameter to be increased. The most effective improvement of

Heat transfer is achieved by extending the housing and the tube bundle. An extension of a conventional one

However, tube bundle leads to an increased pressure drop of the gas flowing through the tube bundle. A performance increase of

Heat exchanger by extending the arrangement are therefore limited due to the increasing pressure loss. The present invention has for its object to provide a heat exchanger for a gaseous medium and a second gaseous or liquid medium, which compared to known

Heat exchangers has a much higher efficiency.

The object is achieved with a heat exchanger for heat transfer between a gaseous medium, in particular a refrigerant, and a second gaseous or liquid medium with a

Heat exchanger housing, in which a tube bundle is arranged and which is characterized in that the tube bundle by a

Lamella arrangement is passed, wherein the lamellae are thermally conductively connected to the tubes to the lamellae arrangement, a gas flow area between at least two connections for the gaseous medium and at least two connections to the supply and

Removing the second gaseous or liquid medium for

Tube bundles are provided. Optionally, a connection for

Relaxation gas (flash gas) be provided.

In contrast to the known heat exchangers is

Heat exchanger according to the invention, the liquid medium through the

Tube bundle passed while the gaseous medium the

Tube bundle flows around. The heat transfer between the two media is also favored by the lamellar arrangement, whereby significant increases in the efficiency of the heat exchanger in

Compared to known heat exchangers are possible.

With an extension of the heat exchanger housing and thus the

Tube bundle and the flow path for the gas also occurs in the heat exchanger according to the invention to a lower pressure drop of the gaseous medium than in the heat exchanger after the state of the art. An increase in performance through an extension of the arrangement is thus possible in the heat exchanger according to the invention in a much larger frame than in the suction gas heat exchangers according to the prior art.

The tube bundle may also have curved sections. The two media can be passed in the same or in the opposite direction through the heat exchanger. Also a multiple passage of the media through the heat exchanger is possible.

As gaseous media other than refrigerants, for example, air, helium, nitrogen, radon, noble or inert gases, propellants, nitrogen oxides, flue gases, industrial gases or water vapor question. The second medium may be liquid or semi-liquid refrigerant or, for example, water, glycol, propylene, brine, a heat transfer fluid, oil, solvents, a low-boiling liquid, but also a gaseous medium such as air, helium, nitrogen, radon, noble or inert gases, propellants, Nitrogen oxides, flue gases, industrial gases or water vapor.

The heat exchanger according to the invention can also be used for

Use compressed air drying.

In a preferred embodiment of the heat exchanger, the tubes of the tube bundle can be arranged substantially parallel to one another. This configuration facilitates the passage of the tubes through the lamellar arrangement. The tube bundle can also as

Micro channel system may be formed, which is provided with fins.

In all variants of the heat exchanger, the pipes can over the

Cross section of the tube bundle evenly or unevenly be distributed. The arrangement of the tubes can be the

Influence the gas flow path in the heat exchanger housing.

Preferably, the tubes of the tube bundle can be arranged in several layers one above the other, wherein the individual layers may have the same or a different number of tubes. The tubes of the various layers can also be arranged offset from one another. It is also possible to use tubes with the same or different diameters. Through this

Different measures can affect both the contact surfaces between the two media as well as the flow paths for the media and optimize the efficiency of the heat exchanger. Which configuration is the most favorable for this also depends on the slat arrangement and on the shape of the

Heat exchanger housing from.

The lamellae arrangement may preferably have a multiplicity of lamellae which are provided with passage openings for the tubes of the tube bundle. Through the slats, the contact surface for

Heat transfer between the gaseous medium and the second gaseous or liquid medium increased by a multiple. In the known heat exchangers, only the peripheral surface of the tubes is available for this purpose. By an appropriate external treatment of the pipes and / or fins in the metal spraying process, the heat transfer can be additionally increased.

The slats can be plate-shaped and be provided with or without punched, surface coatings and / or profiles. Due to the surface design of the slats and their shape and arrangement can also be the contact surfaces for Optimize heat transfer between the two media and the flow paths for the gaseous medium.

In order to ensure that the gaseous medium is in contact with the heat transfer surfaces between the two media for a sufficient length of time and at all possible points, in the gas flow space

Be arranged deflection for the gaseous medium. In particular, these diverters prevent the gaseous medium from flowing from the supplying gas connection to the discharging gas connection in the shortest path.

In this case, the deflection preferably at the

Can be arranged slat arrangement. They can thus be formed as a kind of enlarged lamella and together with the

Slat arrangement and the integrated tube bundle in the

Heat exchanger housing are inserted. The deflection can also rest sealingly on the inner wall of the heat exchanger housing. On the number and shape of the deflection and the pressure loss of the gaseous medium can be adjusted when passing through the heat exchanger.

In order to increase the efficiency of the heat exchanger, the interior is preferably provided with an additional injector for the return of

Flash gas in the medium pressure port of a

Compressor provided. This compressor must perform a multi-stage compression process.

The heat exchanger housing may preferably have a cylindrical shape with, for example, a round, oval, semi-oval or polygonal cross-section. As a material in particular metallic - -

Materials such. As steel, stainless steel, aluminum or copper in question. But also plastics or other pressure-resistant materials such as carbon or glass fiber reinforced materials or Kevlar can be used.

The tubes of the tube bundle can also have different cross sections. They may preferably be round, oval, semi-oval or polygonal. A design as double-wall pipes or segment pipes is possible. In addition, the tubes can be profiled inside and / or outside, treated by flame spraying and in particular be corrugated. As material for the tubes come as well as for the

Slats all thermally highly conductive materials in question, especially metals such as steel, stainless steel, copper or aluminum.

In a cylindrical embodiment of the heat exchanger housing this can be closed in a conventional manner by lateral cover, which can be made as cast or metal turned parts, in particular steel, stainless steel, aluminum, brass or copper. The connections for the second gaseous or liquid medium can be integrated into the lids. The ends of the tubes of the tube bundle can be held on both sides in through holes of tube plates, wherein the

Interspace between the tube plates and the lids of the distribution of the second medium to the tubes or as a collecting space for the effluent from the tubes medium is used.

Hereinafter, a preferred embodiment of a

heat exchanger according to the invention described in more detail with reference to the drawing.

The single FIGURE shows a partially cutaway perspective view of a possible embodiment of an inventive Heat exchanger. The illustrated heat exchanger 10 has a

Heat exchanger housing 11 in the form of a circular cylinder. Inside the housing 11, a lamellar arrangement 12 is provided, through which a tube bundle 13 is passed, of which in the figure, the taken in a tube plate 14 ends of the tubes 15 can be seen. Between the lamellar arrangement 12 with the tube bundle 13 and the inner wall of the housing 11, a gas flow region 16 is provided for a gaseous medium, which flows through a first port 17 into the housing 11 and leaves it again via a second port 18. In the example shown, the connections 17 and 18 are arranged on the same side of the housing 11. However, they could also be arranged at arbitrary angles offset from one another on the housing 11. In addition, it is of course possible to supply or remove the gaseous medium via a plurality of terminals.

The ends of the housing 11 are closed by covers 19, 20, each carrying a port 21, 22 for the second gaseous or liquid medium. Is the terminal 21, the feeding connection, the space between the lid 19 and the tube plate 14 serves as a distributor of the second medium to the individual tubes 15 of the tube bundle 13. On the opposite side of the housing 11, the corresponding space is used to collect the from the Tubes 15 leaking medium before it is discharged through the second port 22. It is also possible to provide a plurality of connections 21, 22 and / or a plurality of tube plates 14, so that a plurality of mutually sealed refrigeration circuits can be produced. In addition to the covers described 19, 20 and tube plates 14 could also be any other distribution systems for

Food of the tube bundle can be used. - -

In the example shown, the lamellae arrangement 12 has a multiplicity of plate-shaped, rectangular lamellae 23, so that the overall result is a rectangular cross-section of lamellae arrangement 12. On the

Top of the fin assembly 12 is arranged a guide plate 24 for the gaseous medium. Next is a baffle 25th

provided, which is also attached to the fin assembly 12 and sealed from the housing 11. This deflection device 25 serves to the gaseous medium flowing through the port 17 in the direction of the terminals 17, 18 opposite

Divert the housing area, so that the gaseous medium the

Lamella arrangement 12 and the tube bundle 13 can flow around on all sides. With the aid of deflection devices 25 it is also possible to regulate the pressure drop of the gas within the housing 11 on its way from the connection 17 to the connection 18.

The diameter of the heat exchanger housing 11 may preferably be between 20 mm and 4000 mm. The cross-sectional shape of the housing 11 may be designed differently from the example shown also polygonal, oval, semi-oval or semicircular. The same applies to the cross section of the lamellar arrangement 12. Again, deviating cross-sectional shapes, for example round, oval or polygonal

Cross sections are realized. In addition, the fins 23 as well as the tubes 15 can be profiled in a wide variety of ways and / or provided with certain surface coatings. It can be different types of slats in different

Material thicknesses are used. They can also be designed with or without a so-called window feature. The provision of guide plates 24 and / or gaseous medium deflection means 25 is optional. These elements can also be dispensed with. It is also possible, an irregular arrangement of the tubes 15 in Provide tube bundle 13. The individual tubes 15 can also vary in diameter and also have different cross-sections from the round shape. On the housing 11 is also a connection (26) with a

Extraction device for a flash gas (flash gas) provided. In the lower region of the housing 11, a further connection 27 for discharging contained in the gaseous medium oil or

Liquid portions that settle in the interior of the housing 11 may be arranged.

Claims

claims

1. Heat exchanger for heat transfer between a

gaseous medium, preferably a refrigerant, and a second gaseous or liquid medium, with a

Heat exchanger housing (11), in which a tube bundle (13)

is arranged, characterized in that the tube bundle (13) is passed through a lamellae arrangement (12), wherein the lamellae (23) are thermally conductively connected to the tubes to the lamellae arrangement, a gas flow region (16) between at least two terminals (17, 18) are provided for the gaseous medium and at least two ports (21, 22) for supplying and discharging the second gaseous or liquid medium to the tube bundle (13).

2. Heat exchanger according to claim 1, characterized in that the tubes (15) of the tube bundle (13) are arranged substantially parallel to each other.

3. Heat exchanger according to claim 1 or 2, characterized in that the tubes (15) over the cross section of the tube bundle (13) are distributed uniformly or non-uniformly.

4. Heat exchanger according to one of claims 1 to 3, characterized

in that the tubes (15) of the tube bundle (13) are arranged in several layers one above the other, wherein the

individual layers have the same or a different number of tubes (15).

5. Heat exchanger according to claim 4, characterized in that the tubes (15) of the different layers are arranged offset from one another.

6. Heat exchanger according to one of claims 1 to 5, characterized

characterized in that the tubes (15) have the same or different diameters.

7. Heat exchanger according to one of claims 1 to 6, characterized

in that the lamellar arrangement (12) has a multiplicity of lamellae (23) which are provided with passage openings for the tubes (15) of the tube bundle (13).

8. Heat exchanger according to one of claims 1 to 7, characterized

characterized in that the lamellae (23) substantially

plate-shaped and with or without Fensterausprägungen, punched, profiled and / or

Surface coatings are designed.

9. Heat exchanger according to one of claims 1 to 8, characterized

in that at least one deflecting device (25) for the gaseous medium is arranged in the gas flow space (16).

10. Heat exchanger according to one of claims 1 to 9, characterized

characterized in that the deflecting means (25) on the

Lamella arrangement (12) are arranged.