WO1997045689A1

WO1997045689A1 - Plate heat exchanger

Info

Publication number: WO1997045689A1
Application number: PCT/CH1997/000195
Authority: WO
Inventors: Arthur FLÜCK
Original assignee: Nek Umwelttechnik Ag
Priority date: 1996-05-24
Filing date: 1997-05-20
Publication date: 1997-12-04
Also published as: ATE189924T1; EP0901602B1; EP0901602A1; DE59701152D1

Abstract

The invention concerns a heat exchanger which has a plate stack (24) and comprises first and second plates (1a, 1b, 1c, 1d) which are arranged alternately in rows and between which first and second channels (11, 12) are formed, these channels being connected via first and second connection regions to first and second connection openings (21, 23, 25). The first connection openings (21, 23), first connection regions and first channels (12) are completely separate from the second (25, 11). The first and second plates (1a, 1b, 1c, 1d) each have on both sides a plurality of substantially straight main channels (13, 17; 14, 16) which are aligned parallel in each plate (1a, 1b, 1c, 1d). The first channels (12) and second channels (11) consist of first and second main channels (13, 14) and third and fourth main channels (16, 17) which mutually form a first angle and are formed on both sides of a first connection plane (7, 7') and a second connection plane (8, 8') in the form of half-channels which are open towards the connection plane. The fourth main channels (17) and second main channels (14) are formed on one side of a first plate (1b, 1d) and second plate (1a, 1c), and the first main channels (13) and third main channels (16) are formed on the other. The plates are metal sheets whose main channels on both sides take the form of beads (5a, 5b) which appear on one side of the metal sheet as depressions and on the other as burr-like projections. On one side of the metal sheet, a contact surface (2a, 2b, 2c, 2d) is provided along the periphery, and, on the other, two contact regions (4a, 4b, 4c, 4d), each enclosing a passage opening, are provided, such that, by joining together the metal sheets with the same sides or planes in each case, contact surfaces (2a, 2b, 2c, 2d) and contact regions (4a, 4b, 4c, 4d) alternately always abut one another and are tightly interconnected, in particular welded or soldered together, in order to separate the first and second channels (12, 11) in a leaktight manner.

Description

PLATE HEAT EXCHANGER

The invention relates to heat exchangers according to the preamble of claim 1 and to a device for performing a cyclic process.

Heat exchangers should enable the fastest possible and complete heat transfer between two fluids with different starting temperatures. For this purpose, the two fluids are guided on both sides by heat-conducting contact surfaces. In order to obtain the largest possible active contact area, the fluids are usually led through complex channel systems. Tube bundle exchangers enable efficient duct routing for heat exchange, but are very complex. Plate heat exchangers are much simpler in construction. Plate heat exchangers are now known, in which channels for one and the other fluid are alternately arranged between plates arranged in parallel in such a way that similarly complex channel systems are produced as in tube bundle exchangers. In particular, the channels for both fluids are designed in such a way that flow paths that are as long and highly structured as possible are created.

It has now been shown that such plate heat exchangers have a high flow resistance when using an evaporating or condensing fluid due to the complex duct arrangement, or that individual duct regions are not or only poorly flowed through by at least one phase of at least one fluid, which leads to a reduction in heat exchange. In particular when such a heat exchanger is used as an evaporator, vapor bubbles which arise can remain in individual channel sections and hinder the passage of gas and or liquid. Corresponding problems arise when used as a condenser, the passage being prevented being caused by remaining drops. The object of the invention is to find a simply constructed heat exchanger which also ensures optimal heat exchange when used as an evaporator or condenser.

The problem is solved by realizing the generic features together with the characterizing features of claim 1 or by the features of claim 7.

When the task was solved, it was recognized that the first channel system must be designed such that at least some of the channels as first and second main channels for at least one first fluid over their entire length essentially along a first and a second main direction run. In order to achieve a flow capability with a small width, first connection areas are preferably arranged in such a way that they are directly connected by at least one, but in particular by several main channels.

The two main directions run at an angle of less than 60 °, in particular less than 40 °, preferably of essentially 30 ° to one another.The main directions are so orientable for operation that at least one main direction makes an angle to the vertical which is less than 30 ° , in particular less than 20 °, optionally substantially 0 °. However, both main directions can preferably be aligned such that they are inclined between 10 ° and 20 °, preferably both essentially by 15 ° to the vertical.

In the case of evaporative heat exchangers, the two first connection areas of the first channels for the first fluid are arranged on two mutually opposite circumferential areas of the plates and possibly merge into one another. In the operating state, the two first connection areas are arranged one above the other and are at least in part of the main channels directly connected to each other. Because at least one main direction to the vertical encloses an angle that is less than 30 °, in particular less than 20 °, possibly essentially 0 °, or preferably 15 °, the first two connection areas are directly through Main channels connected, which run in a direction that is inclined less than 30 ° to the vertical. This ensures a good rise of gas bubbles or, in the case of condensation heat exchangers, a good sinking of condensed liquid drops.

In order to enable the heat exchanger to be replaced as flexibly as possible with a simple construction, the second channels are constructed similarly to the first and include third and fourth main channels for the second fluid, which essentially run along a main direction. The first and second or the third and fourth channels are optionally connected to one another in outer end regions, but preferably in all crossing regions. The first and second or third and fourth main channels are formed on both sides of a first and second connection level as open channels that are open to the connection level. In the intersection areas, the first and second or third and fourth main channels lie openly against one another in the first and second connection levels, so that the first and second channels each have to be regarded as channel networks formed by the main channels with the connections in the intersection areas . Plate stacks with the described channel networks are constructed from alternately adjoining first and second plates, the fourth and second half channels being formed on one side of the first and second plates and the first and third half channels on the other. All channels of a plate run essentially parallel to each other.

In order to easily achieve a complete separation between the two duct systems, the two are second Connection areas for the second channels carrying the second fluid are formed as chambers running transversely to the plates. These two chambers are mutually connected only via the second channels and completely separated from the first channels. For this purpose, the second connection regions are spaced apart from one another transversely to the bisecting angle of the two main directions, so that they are not directly connected to one another by individual main channels. The connection is thus only possible through at least two interconnected channel sections, at least one channel section being aligned in the first and at least one in the second main direction.

In order to make the plate heat exchanger as simple as possible, it is preferably constructed from essentially identical plates or sheets. Grooves running on both sides in a main direction are arranged in each plate. Since the plates are preferably designed as sheets, these grooves provided on both sides can be formed as sinks by a pressing or stamping process, which appear as recesses on one side of the sheet and as burr-shaped projections on the other side of the sheet. In order to be able to form two completely separate channel systems by connecting the plates, a first flat contact surface is provided along the entire plate circumference in a first plane that borders the plate on a first side. In a second plane bordering the plate on the second side, two contact areas are provided, each of which is arranged around a passage opening. The plates or sheets of the heat exchanger close together with the same sides or levels. Correspondingly, alternately, contact surfaces and contact areas always adjoin one another and are each tightly connected to one another, in particular smoldered or soldered to one another. The substantially parallel beads or their longitudinal axes enclose an angle to a normal plane of the connecting line between the centers of the passage openings, which angle is less than 30 °, in particular less than 20 °, but is preferably essentially 15 °. The beads start from the first level and have their ridge lines protruding from the rear in the second level. The depressions between the ridge lines preferably have essentially the same shape as the beads, that is to say in cross section the parallel beads form a wavy line, in particular with half-waves in the shape of a trapezoid, the small side of which is rounded. In order not to unnecessarily reduce the wettable area on both sides of the ridge lines, the rounding of the ridge line preferably has a small radius.

The plate packing of the heat exchanger constructed from the plates or sheets described above can be connected with its two first or second connection areas to first or second connection lines. The design of the connection areas, the connection lines and the connections between them can be adapted to the respective use.

For fluids that only occur in one phase in normal operation in the heat exchanger, the connections are preferably designed so that there is a clear separation between inflow and outflow for both fluids, or that both fluid volumes passed through the heat exchanger must flow completely through one channel system each. It can be expedient to design the two channel systems and their connection areas essentially the same, in particular as described for the second channels. If necessary, the complete penetration of a duct network is limited to one fluid and the other fluid forms a bath, for example, in which the plate packing with the closed duct system is opened. is taken. However, at least some of the bath fluid must flow through main channels in the plate pack, for example as a convection flow, in order to ensure a sufficiently large heat exchange.

For heat exchangers in which at least part of the first fluid undergoes a phase transition, it is expedient not to design the first two connection areas to be completely separate from one another. As a result, incompletely separated phase components in the heat exchanger can be fed to the respective separated main components of the two phases. For this purpose, for example, the plate pack is preferably arranged partially in m or above a bath area for the first fluid

In the case of an evaporator, the liquid level in the working state is selected such that a large part of the plate packing or of the first channel network is filled with the liquid phase of the first fluid. As a result, a large area of the contact area between the two fluids is used to heat the fluid to be evaporated. In the case of a high liquid level, in particular if the plate pack is essentially completely absorbed in the first liquid, care must be taken that the gas outlet is arranged in such a way that no liquid can escape, or that liquid escaping from one

Separator can be returned to the bathroom. Gas escaping in the liquid can rise through the first and / or second main channels into the gas area. Gas that arises when you enter the bath due to relaxation or in the bath can rise from the side of the plate pack through the bath into the gas area.

A particularly compact and effective evaporator or evaporation heat exchanger comprises a housing with a refrigerant attachment that has been attached for the liquid phase of the refrigerant and with a separator in the highest area of the housing above a liquid direction arranged refrigerant outlet for the gas phase of the refrigerant, as well as a plate pack with inlet and outlet connections for a heat transfer fluid through the housing. In the operating state, the plate pack is largely in the liquid phase of the refrigerant. In the housing, a relaxation chamber connects to the refrigerant inlet opening, from which gas escaping during the expansion can rise into the gas area above the liquid and can reach the refrigerant outlet opening there. The liquid phase passes directly from the expansion chamber, if necessary, or via a level chamber into the bath area with the plate packing, where the liquid essentially fills the first channels up to the liquid level. The coolant fluid flows through the second channels and loses the heat necessary for the evaporation of the refrigerant.

In the case of a condenser, the liquid level is selected such that it lies below the condenser plate pack, at least in the working state, so that liquid drops occurring in the plate pack flow down through first and / or second main channels and out of the plate pack can exit. The heat of condensation is absorbed by the recooling agent passed through the second channels of the condenser plate pack.

By combining an evaporation heat exchanger with a condensation heat exchanger, both of which comprise a plate pack described above, a simple and efficient refrigeration machine or heat pump can be put together. The gas is led from the evaporator to the condenser via a compressor. The liquid phase of the refrigerant reaches the evaporator from the condenser via a throttle valve.

Because the evaporator and the condenser are used as communicating vessels due to the line with the throttle are at standstill or when the compressor is switched off, both have a refrigerant level essentially at the same level. In the operating state, the pressure in the compressor lowers the level in the condenser and raises it in the evaporator. By selecting the volume of the liquid refrigerant to be smaller than the refrigerant absorption volume of the evaporator, it can be prevented that liquid refrigerant flows out of the evaporator and reaches the compressor. In order to prevent the pressure built up in the compressor from discharging all of the condensed refrigerant from the condenser and thus gas directly from the condenser to the evaporator, it must be ensured that the compressor pressure is always lower than the hydrostatic pressure at the throttle valve when the all liquid refrigerant is on the evaporator side of the throttle valve.

The relative vertical arrangement of the evaporator and the condenser is selected such that the refrigerant level in the evaporator and in the condenser is in a desired range relative to the plate packs in the operating state. The condenser plate pack should lie essentially above the corresponding mirror and the evaporator plate pack should largely be in the liquid phase of the refrigerant. Due to the essentially identical structure of the evaporator and condenser, the refrigeration machine can be easily dimensioned, installed and regulated.

Heat exchangers according to the invention can be used in any devices for carrying out processes with a heat exchange step. Due to the essentially straight main channels for a first fluid, which can be aligned at a small angle to the vertical, escaping gas as well as heated liquid of a bath in the sense of a guided convection flow can flow out in these channels. The main channels for the first fluid also allow good drainage of condensate drops. Corresponding configurations of the connection areas make it possible to use the first and second channels according to the respective use with direct main channels between the connection areas or with connections via at least two differently oriented channel sections.

The processes in which heat exchangers according to the invention can be used also include fractional evaporation and distillation. The heat exchangers according to the invention are thus versatile and have a simple structure.

The drawings illustrate an embodiment of the invention, to which the invention is, however, not restricted. Show it

1: a view of two adjoining plates,

Fig. 2- a section (II-II of FIG. 1) through four

3 and 4: a view of first a) and second b) channels formed between two plates, FIG. 5: a longitudinal section through a heat exchanger, FIG. 6: cross sections through a heat exchanger, wherein a) through the plane AA and b) goes through BB according to FIG. 5; and FIG. 7: a schematic illustration of a refrigeration machine

1 illustrates two adjoining plates of a heat exchanger plate packing. The plates are in the form of sheets la and lb in the form of circular disks with a ring-shaped contact surface 2a, 2b forming the outer edge of the disk, with two contact areas 4a, 4t> arranged around passage openings 3a, 3b and with parallel directed main channels formed by beads 5a, 5b, arranged on both sides. The beads 5a extend over the entire sheet metal area, which is not designed as a contact surface 2a and not as a contact area 4a. In the illustration according to FIG. 1, the beads 5a of an upper plate la project upwards from a second plane - the plane of the drawing - in which the contact surface 2a lies. The beads 5b of a lower plate 1b project downward from the same plane, so that after the contact surface 2a of the upper plate 1a has been tightly connected to the contact surface 2b of the lower plate 1b, a second channel system is formed which is formed by the main channels Through openings 3a, 3b is accessible.

In the illustrated embodiment, the axes of the main channels of the upper and lower plates la, lb are inclined at a first angle of 30 ° to one another. The main channels, which are open to one another, are connected to one another in the connection areas 6, in which they lie opposite one another. The contact areas 4a, 4b are facing away from one another, so that a second fluid can enter or exit the second channel system between the illustrated sheets 1a and 1b through the through openings 3a, 3b. The formation of the sheets la, lb and the second channel system formed by the main channels is further illustrated by the section shown in FIG. 2.

Fig. 2 shows a section (II-II, according to Fig. 1) through four sheets la, lb, lc, ld. The view shown in FIG. 1 is labeled BB in FIG. 2, this level being referred to as the first level 7. Another first level 7 'lies between the sheets 1b and 1c. The above-mentioned second level is identified by 8 between the sheets la and 1b and by 8 'between the sheets 1c and 1d. The sheets la and lb are in contact with one another with their contact surfaces 2a and 2b in the second plane 8. The of the two Bumps 5a and 5b which go away from level 8 extend with their outer ridge lines 9a and 9b, like the contact areas 4a and 4b, to the first levels 7 and 7 '. The second channel system is sealed off by the tight connection of the contact areas 4b and 4c, the sheets 1b and 1c. The second chambers 10, which extend through the through openings, are connected to the second channels 11 formed between the two sheets 1a and 1b and form the second connection regions. The main channels of the second channel system depart from the connecting areas 6 as half channels in the two directions of the beads, which is indicated by the hatching shown.

The first channels 12 are formed between the two sheets 1b and 1c, analogous to the second channels 11 on both sides of the first plane 7 ', half channels extend in the directions of the beads. The first connection areas are arranged between the contact surfaces 2b and 2c. In use of the plate package in a bath or as Konden¬ sator the division of the annular first connection regions in an influx and ^p ιnen Ausstrόmbe- yields rich by the operation, in particular by the Flus¬ sigkeitsspiegel of the bath or by di ^ fact that drops of condensate can only flow out through downward-feeling channels. If necessary, however, the first connection regions are delimited by tight connections between the contact surfaces 2b and 2c, or, as in the case of the second chambers, 10 clearly defined orsto chambers are formed.

Fig. 3 and Fig. 4 show the characteristically different flow paths for the two fluids for an evaporation heat exchanger using two differently oriented plate packs. Dabe iist _l eweil s depicting the lung a) a layer Ans AA and b) e ine view B - B as shown in FIGS. 2nd The first channel system 1? is trained that direct channels between the lower and the upper edge region of the plate pack, or the sheets 1, as first and second main channels 13 and 14 run over their entire length along a first and a second main direction. The fluid level 15 determines in which channels the liquid phase of the first fluid enters and thus also the connection area in the liquid flows. The upwardly open ends of the channels 13 and 14 open into the connection area into which the gas produced flows out.

Due to the fact that the first and / or second channels are only slightly inclined to the vertical and there is a direct connection between the inflow connection area or the channel area in the gas bubble and the outflow connection area, there is hardly any impeded flow 13a and 14a ensured by the first fluid In the intersection areas 6 with the liquid phase, two partial flows in the adjoining first and second main channels flow crosswise past one another with boundary layer contact, which leads to a slight turbulence excitation in both partial flows Channel walls adjacent heated boundary layer dissolved and the heat transfer between the channel wall and the first fluid improved.

The two main directions run at an angle of less than 60 °, in particular less than 40 °, preferably of essentially 30 ° to one another. The main directions can be aligned for operation such that at least one

Main direction to the vertical an angle that is less than 30 °, in particular less than 20 °. As shown in FIG. 4, the channels 14 are preferably oriented essentially vertically. 3, however, both main directions are inclined essentially by 15 ° to the vertical. The first and / or the second main channels ensure the selected orientations a good rise of gas bubbles or, in the case of condensation heat exchangers, a good decrease in condensed liquid drops.

The second channels are constructed analogously to the first and include third and fourth main channels 16, 17 for the second fluid, which essentially run along a main direction and are closed at the ends by the contact surfaces 2a, 2b connected to one another. In the intersection areas 6, the third and fourth main channels openly abut each other on both sides of the second connection levels 8, 8 '. Correspondingly, the second channel system that arises is constructed in the form of a network. Because the second connection areas 10 have small dimensions and are arranged on a line running transversely to the main directions, there are no main channels 16, 17 which connect the two connection areas 10 directly to one another.

The flow paths 18 extend over at least two, but preferably over at least three, main channel sections 16, 17 and the intersection areas 6 connecting them. The second channel system is suitable for a fluid which does not undergo a phase transition, in particular for a liquid. The second fluid must therefore travel a long way with strong ones between the two second connection regions 10

Make changes of direction. In addition, the turbulence is also increased in partial flows flowing past one another, so that the partial flows are well homogenized and the heat transfer is optimized. The duct network formed by the third and fourth main ducts 16, 17 is advantageous regardless of the orientation of the plate pack (FIGS. 3 and 4 b).

5 and 6 show a particularly compact and effective evaporator or evaporative heat exchanger, which comprises a housing 20 with a laterally attached refrigerant inlet opening 21 for the liquid phase of the refrigerant and with a refrigerant outlet opening 23 for the gas phase of the refrigerant arranged in the highest housing area above a liquid separation device 22, as well as a plate packing 24 with inlet and outlet connections 25 for a heat transfer fluid through the housing 20. In the operating state, the plate pack 24 is largely in the liquid phase of the refrigerant. In the housing 20, a expansion chamber 26 connects to the refrigerant inlet opening 21, from which gas escaping during the expansion flows via a partition wall 27 and under a deflection element 28 through the gas region 29 lying above the liquid and from there via lateral guide elements 22a of the separating device 22 can reach the refrigerant outlet opening 23.

The liquid phase passes directly from the relaxation chamber 26, or via a level chamber 30, which is formed between a housing wall 20a or the relaxation chamber 26 and the partition wall 27, a bath area 31 with the plate pack 24, where the liquid fills the first channels essentially up to a liquid level 32. In order to reduce the volume of the bath area, two filling bodies 39 are preferably arranged on both sides of the plate pack 24 between the latter and the inner wall of the housing 20. In the lowest-lying housing area, a supply channel 40 remains free, through which the liquid can reach the first channels connected in parallel. The refrigerant carrier fluid flows through the inlet and outlet connections 25 and through the second channels of the plate pack 24 and thereby loses the heat necessary for the evaporation of the refrigerant.

7 shows a refrigeration machine or heat pump 33, with an evaporation heat exchanger 34 and a condensation heat exchanger 35, both of which comprise a plate packing described above. The gas is led from the evaporator 34 to the condenser 35 via a compressor 36. The The liquid phase of the refrigerant passes from the condenser 35 via a throttle valve 37 or an orifice into the evaporator 34. The evaporator 34 comprises refrigerant connections 25 and the condenser 35 recooling connections 38. It goes without saying that all known Ver¬ vaporizable refrigerant and all appropriate refrigerant and recooling agents can be used.

Since the evaporator 34 and the condenser 35 are used as communicating vessels due to the line with the throttle 37, when the compressor 36 is at a standstill or when the compressor 36 is switched off, a refrigerant level is set substantially at the same level. In the operating state, the pressure in the compressor 36 lowers the mirror 35a in the condenser 35 and raises the mirror 34a in the evaporator 34.

The relative vertical arrangement of the evaporator 34 and the condenser 35 is selected such that the refrigerant level in the evaporator and in the condenser 34a and 35a in the operating state lies in a desired range relative to the plate packs 24a and 24b. The condenser plate pack 24b should lie essentially above the corresponding mirror 35a and the evaporator-l'larton pack 24a should largely lie in the liquid phase dt s refrigerant. Because the evaporator 34 and condenser 35 are of essentially the same construction, the refrigerator can be easily dimensioned, assembled and regulated.

Claims

claims

1. Heat exchanger with a plate packing (24) consisting of alternately arranged first and second plates (la, lb, lc, ld) between which first and second channels (12, 11) are formed, which have first and second connection areas with first and second connection openings (21, 23, 25) are connected, the first connection openings (21, 23), connection areas and channels (12) being completely separated from the second (25, 11), characterized in that the first and second plates (la, lb, lc, ld) each comprise on both sides a plurality of substantially straight main channels (13, 17; 14, 16) aligned in parallel in each plate (la, lb, lc, ld) and the first (12) or second channels (13) consist of first and second (13, 14) or third and fourth main channels (16, 17) which open at a first angle to one another and which are on either side of a first (7, 7 ') or second Connection level (8,8 ') as open to the connection level e

Half channels are formed, the fourth (17) or second (14) on one side of a first (lb, ld) or second plate (la, lc) and the first (13) or third main channels (16 ) are trained.

2. Heat exchanger according to claim 1, characterized in that the first angle is less than 60 °, in particular less than 40 °, preferably substantially 30 °

3. Heat exchanger according to claim 1 or? , characterized in that the first and second plates (lb, ld; la, lc) are of identical design, along the entire plate circumference of each plate (la, lb, lc, ld) on a first, leather plate ( la, lb, 1 c, ld) on a first side bordering plane (7,7 ') eιrκ ³ flat contact surface (2a, 2b; 2c, 2d) is provided and in a second plane (8,8 ') bordering each plate (la, lb, lc, ld) on the second side, two contact areas (4a, 4b, 4c, 4d) are provided, so that the anemander connection of the plates (la, lb, lc, ld) always with the same sides alternately always contact areas (2a, 2b; 2c, 2d) and contact areas (4a, 4b, 4c, 4d) abut one another, which are each tightly connected to one another, in particular smoldered or soldered together, for the tight separation of the first and second channels (12, 11).

4. Heat exchanger according to claim 3, characterized in that the plates are sheets (la, lb, lc, ld), the main channels on both sides (13, 17; 14, 16) are formed as beads (5a, 5b) appear on the one side of the sheet as depressions and on the other side of the sheet as a burr-shaped protrusion and that at least one of the following features is provided a) the substantially parallel beads (5a, 5b) of each sheet (la, lb, lc, ld) or their longitudinal axes enclose an angle to a normal plane of the connecting line between the centers of the passage openings (3a, 3b, 3c, 3d), which is less than 30 °, especially less than 20 °, but preferably in is substantially 15 °, b) the beads (5a, 5b) start from the first level (7,7 ') and have their grains on the back protruding from the second face (8,8'), and c) the recesses between the ridge lines (9a, 9b) have _^ r substantially the same shape as the beads (5a, 5b).

5. Heat exchanger according to one of claims 1-4, characterized in that the plate pack (24) is housed in a housing (20) with first connection openings (21, 23), a first connection opening (23). in an upper housing area is arranged and that at least one of the following features is provided, a) a second angle between the vertical and an axis along main channels (13, 14, 16, 17) is smaller than 30 °, in particular smaller than 20 ° and is preferably substantially 0 ° or 15 °; b) the first connection areas are partial areas of the housing interior adjoining the plate packing, so that the first channels (12) are accessible directly from the housing interior; and c) the second connection regions are designed as chambers (10) which run through the plate pack (24) and are connected to through openings (25) in the housing (20).

6. Heat exchanger according to claim 5, characterized in that the top first connection opening (23) is designed as a gas outlet opening and a further first connection opening (21) is designed as a liquid inlet opening, at least one of the following features being provided a) the gas outlet opening (23) a liquid separator (22) is assigned to prevent the escape of liquid drops, - b) a relaxation chamber (26) is connected to the liquid inlet opening (21) to relax the liquid so that the escaping gas is directed upwards the gas outlet opening (23) can escape; and c) a Nieveau chamber (30) is arranged between the relaxation chamber (26) and the receiving area for the plate pack (24).

7. Heat exchanger according to claim 5, characterized in that the overhead first Λnschlußöffnunq as

Gas inlet opening and a further first connection - opening in the lowest-lying housing area is designed as a liquid outlet opening.

8. A device for carrying out a cycle with a heat exchanger operable as an evaporator (34) according to claim 6, a heat exchanger operable as a condenser (35) according to claim 7, a compressor (36) and a throttle valve (37) or an orifice, wherein a refrigerant can be evaporated in the first evaporator channels (12) by absorbing heat from the refrigerant fluid flowing through the second evaporator channels (11) and can be conducted through the condenser (35) via the compressor (36) after the condensation by means of the release of heat to a cooling medium flowing through the second condenser channels through the throttle valve (37) or the orifice m to flow the evaporator (34).

9. The device according to claim 8, characterized in that the device is a refrigerator or a heat pump.