CA3014091A1

CA3014091A1 - Cross-flow plate heat and/or moisture exchanger

Info

Publication number: CA3014091A1
Application number: CA3014091A
Authority: CA
Inventors: Kai Klingenburg
Original assignee: Klingenburg GmbH
Current assignee: Klingenburg GmbH
Priority date: 2016-02-11
Filing date: 2016-02-11
Publication date: 2017-08-17
Also published as: EP3414508B1; EP3414508A1; PL3414508T3; ES2770318T3; WO2017137054A1; US20190086156A1; RU2018130819A

Abstract

The invention relates to a cross-flow plate heat and/or moisture exchanger having plates which are arranged above, below or next to one another, and form alternating flow passages for a first and a second fluid. According to the invention, for a cross-flow plate heat and/or moisture exchanger of this type, in order to achieve an improved transfer performance and an increased pressure stability in relation to differential pressures between the two fluids, each plate (2) has a first cross-flow region (4), a following counter flow region (6) in the flow direction of the first cross-flow region (4), and a following second cross-flow region (10) in the flow direction of the counter flow region (6). The cross-flow regions (4, 10) of neighbouring plates are to form flow channels (5, 11) running approximately perpendicular to one another, wherein the counter flow regions (6) of neighbouring plates form counter flow channels (7) running approximately parallel to one another and the first or second cross-flow region (4, 10) of each plate (2) corresponds to the second or first cross-flow region of each neighbouring plate in terms of the dimensions thereof, and is arranged above, below or next to same, and wherein the counter flow region (6) of each plate (2) corresponds to the counter flow region of each neighbouring plate (3) in terms of the dimensions thereof, and is arranged above, below or next to same.

Description

WO 2017/137054 Al CROSS-FLOW PLATE HEAT AND/OR MOISTURE EXCHANGER
The invention relates to a cross-flow plate heat and/or moisture exchanger having plates which are arranged above, below or next to one another and form alternating flow passages for a first and a second fluid.
Based on the above-mentioned state of the art the invention is based on the requirement to provide an improved cross-flow plate heat and/or moisture exchanger, which on the one hand exhibits better transfer performance during the transfer of heat and/or moisture between the two fluids and which moreover has increased pressure stability in relation to differential pressures between the two fluid flows.
According to the invention this requirement is met in that each plate of the cross-flow plate heat and/or moisture exchanger has a first cross-flow region, a counter-flow region following the first cross-flow region in flow direction and a second cross-flow region following the counter-flow region in flow direction, in that the cross-flow regions of neighbouring plates form flow channels running approximately perpendicular to each other, in that the counter-flow regions of neighbouring plates form flow channels running approximately parallel to one another, in that the first or the second cross-flow region of each plate in terms of its dimensions corresponds to the second or first cross-flow region of each neighbouring plate and is arranged above, below or next to the same, and in that the counter-flow region of each plate in terms of its dimensions corresponds to the counter-flow region of each neighbouring plate and is arranged above, below or next to the same.

- 2 -Due to this design of the two differently constructed plates, which are combined to form the cross-flow plate heat and/or moisture exchanger, it is achieved that the two fluids flowing through the cross-flow plate heat and/or moisture exchanger flow essentially anti-parallel to one another, as a result of which the efficiency of the cross-flow plate heat and/or moisture exchanger is considerably improved in comparison to corresponding aggregates known from the state of the art. Due to the flow channels running perpendicular to one another a mechanically stable design of the cross-flow plate heat and/or moisture exchanger is obtained. Since a counter-flow region is provided in each flow passage of the cross-flow plate heat and/or moisture exchanger according to the invention, it is ensured that the two fluids in this counter-flow region are guided past each other in an approximately anti-parallel manner. According to the invention it has become possible to steer the flow direction of the first fluid in direction of the entry of the second fluid so that the temperature or the moisture of the first fluid can move closer to the entry temperature or moisture of the second fluid. Similarly the temperature and/or the moisture of the second fluid can move closer to the entry temperature or moisture of the first fluid. By proceeding in this way high degrees of transfer are achievable which lie in the range of up to 90%.
The first cross-flow region of each plate causes the respective fluid flow to be evenly distributed across the counter-flow region of each plate. Due to the difference in design of the neighbouring plates, these can mutually support each other very well, wherein nevertheless, in the area of the respective counter-flow regions, an approximately parallel progression of the respective flow channels is made possible.

- 3 -In order to ensure that the stability of the plate packet of the cross-flow plate heat and/or moisture exchanger according to the invention also in the area of the counter-flow regions of the plates is of high quality even for the most varied pressures in the different fluids, it is advantageous if the counter-flow channels of the cross-flow region of each neighbouring plate extend at a slight incline of preferably 5 to 25 degrees. This ensures an approximately parallel progression of the counter-flow channels formed by the neighbouring plates in the neighbouring flow passages, wherein moreover it is ensured that the neighbouring plates are mechanically firmly supported against each other.
When the direction of counter-flow channels of the counter-flow regions of the plates changes, turbulences can be initiated in the flows of the two fluids, which can contribute to an improvement of the transfer conditions of heat and/or moisture right through the plates between the two fluids.
In order to keep the installation cost for the cross-flow plate heat and/or moisture exchanger according to the invention to a minimum and in order to be able to ensure reliable sealing on the plate edges at a minimum of engineering effort, it is advantageous if the plates are shaped in the form of a rectangle or a square.
According to an advantageous embodiment of the cross-flow plate heat and/or moisture exchanger according to the invention the counter-flow regions of each plate are shaped as an approximate oval or ellipse extending between two opposing corners of the plate.

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- 4 -According to a further advantageous embodiment of the cross-flow plate heat and/or moisture exchanger according to the invention the general flow direction A, B through the cross-flow plate heat and/or moisture exchanger, of the two fluids separated from each other by the plates, is chosen such that the two fluids flow through the counter-flow regions of the cross-flow plate heat and/or moisture exchanger in counter direction, i.e. approximately anti-parallel.
If walls of the flow channels of the cross-flow regions, which are arranged between the plates, are formed in a steady or uninterrupted manner, the flow conditions in the cross-flow regions of the cross-flow plate heat and/or moisture exchanger according to the invention are comparatively regular and orderly, which for certain requirement profiles on the cross-flow plate heat and/or moisture exchanger is convenient and advantageous.
If the requirement profiles for the cross-flow plate heat and/or moisture exchanger according to the invention are of a different kind, i.e. if more turbulent flow conditions are desired in the cross-flow regions thereof, it is convenient if walls of the flow channels of the cross-flow regions arranged between the plates comprise interruptions.
Particularly advantageous materials for the plates of the cross-flow plate heat and/or moisture exchanger according to the invention have proved to be aluminium and plastic, preferably PET plastic, in particular then, when the cross-flow plate heat and/or moisture exchanger according to the invention is to be used merely for temperature transfer between the two fluids.

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- 5 -If the cross-flow plate heat and/or moisture exchanger according to the invention is to be used also or predominantly for moisture or enthalpy exchange between the two fluids, it is advantageous if the plates are configured as membrane plates. In this case each membrane plate comprises a membrane layer and a carrier layer. By means of the membrane layer enthalpy can be transferred between the two fluids. The at least one carrier layer is configured perforated. By means of the perforated carrier layer the membrane plate can be given a specifiable mechanical strength and a spatial structure, wherein both the mechanical strength and the spatial structure can be permanently maintained.
The membrane layer of the plates is conveniently formed of a suitable plastic material, preferably a polyurethane or a polymer material.
The carrier layer of the plates is conveniently formed of a suitable fleece material, preferably a polyester material.
The invention will now be described in detail by way of an embodiment with reference to the drawing, in which figure 1 shows an embodiment of a plate of the first design for a cross-flow plate heat and/or moisture exchanger according to the invention comprising two differently constructed plates;
figure 2 shows an embodiment of a plate of the second design for a cross-flow plate heat and/or moisture exchanger according to the invention comprising two differently constructed plates; and figure 3 shows a schematic diagram of a cross-flow plate heat and/or moisture exchanger according to the invention comprising embodiments of plates depicted in figures 1 and 2.

- 6 -A cross-flow plate heat and/or moisture exchanger 1 according to the invention shown in a schematic diagram in figure 3 consists of a plate packet composed of plates 2, 3 of different design or construction. Within the plate packet the plates 2 and the plates 3 are arranged in an alternating manner, i.e. a plate 2 of the first construction type is followed respectively by a plate 3 of the second construction type. Accordingly each plate 2 of the first construction type has two neighbouring plates 3 of the second construction type and vice-versa. In the case of the embodiment shown in figure 3, the plates 2, 3 are arranged on top of each other. It is, of course, possible to arrange the plates 2, 3 adjacently to each other.
The two sides of the plates 2, 3 facing each other limit flow passages for a first fluid which flows through the cross-flow plate heat and/or moisture exchanger 1 of figure 1 in a general direction indicated by arrows A, and for a second fluid, which flows through the cross-flow plate heat and/or moisture exchanger 1 of figure 2 in a general direction indicated by arrows B. The general direction A of the first fluid is approximately perpendicular to the general direction B of the second fluid.
The flow passages for the first fluid and for the second fluid are arranged in an alternating manner in the plate packet shown in figure 3 made up of plates 2, 3.
The flow passages for the first fluid are determined by the design shown in figure 1 of the plate 2 of the first construction type. The flow passages for the second fluid are determined by the design shown in figure 2 for the plate 3 of the second construction type.

- 7 The plates 2, 3 of the cross-flow plate heat and/or moisture exchanger I may be made of any suitable material, e.g.
aluminium or a PET material.
If the cross-flow plate heat and/or moisture exchanger 1 is also to be used essentially for moisture or enthalpy exchange between the two fluids which flow through the same, the plates 2, 3 of the cross-flow plate heat and/or moisture exchanger I are configured as membrane plates. The respective membrane plates consist of a membrane layer by means of which enthalpy can be transferred between the two fluids, and at least one perforated carrier layer by means of which a specifiable mechanical strength and a spatial structure can be imparted to the membrane plate and be maintained therein.
The membrane layer of plates 2, 3 is then formed from a suitable plastic material, in particular a polyurethane or a polymer material.
The carrier layer of the plates 2, 3 is then formed from a suitable fleece material, preferably from a polyester fleece or similar.
The flow passages, which are provided in the cross-flow plate heat and/or moisture exchanger 1 for the first fluid, are designed according to the structure of plate 2 of the first construction type as depicted in the following in figure 1.
In case of the embodiment shown in figure 1 the plate 2 has a first cross-flow region 4, into which the first fluid enters.
The first cross-flow region 4 comprises flow channels 5 extending in parallel, through which the first fluid is guided to a counter-flow region 6 following the first cross-flow region 4. In the embodiment shown the counter-flow

- 8 -region 6 comprises a larger number of counter flow channels 7 in comparison to the number of flow channels 5 of the first cross-flow region 4. The counter-flow channels 7 are arranged at an incline to the flow channels 5. Moreover the counter-flow channels 7, as from a certain length, comprise length portions of varying direction. The varying length of the counter-flow channels 7 stems from the fact that the counter-flow region 6 of the first plate 2 extends from the right upper corner 8 thereof in figure 1 to the left lower corner 9 thereof in figure 1 and comprises an elliptical or oval shape tapering in direction of the corners 8, 9.
The first fluid is guided through the multiplicity of counter-flow channels 7 to a second cross-flow region 10 of the plate 2. The second cross-flow region 10 comprises flow channels 11, which extend in parallel to the flow channels 5 of the first cross-flow region 4 and which respectively extend in the general direction A, in which the first fluid flows through the cross-flow plate heat and/or moisture exchanger 1.
The flow passages, which are provided in the cross-flow plate heat and/or moisture exchanger 1 for the second fluid, are designed according to the structure of plate 3 of the second construction type as depicted in the following in figure 2.
In case of the embodiment shown in figure 2 the plate 3 has a first cross-flow region 12, into which the second fluid enters. The first cross-flow region 12 comprises flow channels 13 extending in parallel, through which the second fluid is guided to a counter-flow region 14 following the first cross-flow region 12. In the embodiment shown the counter-flow region 14 comprises a larger number of counter flow channels 15 in comparison to the number of flow channels 13 of the first cross-flow region 12. The counter-flow k

- 9 -channels 15 are arranged at an incline to the flow channels 13. Moreover the counter-flow channels 15, as from a certain length, comprise length portions of varying direction. The varying length of the counter-flow channels 15 stems from the fact that the counter-flow region 14 of the second plate 3 extends from the right upper corner 16 thereof in figure 2 to the left lower corner 17 thereof in figure 2 and comprises an elliptical or oval shape tapering in direction of the corners 16, 17.
The second fluid is guided through the multiplicity of counter-flow channels 15 to a second cross-flow region 18 of the plate 3. The second cross-flow region 18 comprises flow channels 19, which extend in parallel to the flow channels 13 of the first cross-flow region 12 and which respectively extend in the general direction B, in which the second fluid flows through the cross-flow plate heat and/or moisture exchanger 1.
As already explained, the plate packet of the cross-flow plate heat and/or moisture exchanger 1 is constructed by arranging the differently constructed plates 2, 3 depicted in figure 1 and figure 2 in an alternating manner on top of each other. As can be seen in figure 1 and figure 2, the first cross-flow region 4 of plate 2, in terms of its layout and its dimensions, corresponds to plate 3 depicted in figure 2.
Analogously the second cross-flow region 10 of plate 2 depicted in figure 1, in terms of its shape and its dimensions, corresponds to the first cross-flow region 12 of plate 3 depicted in figure 2. The first fluid and the second fluid, in the cross-flow regions 4, 10, 12, 18 of the two plates 2, 3, flow in their general directions A or B and thus approximately perpendicular to each other.

- 10 -The plates 2, 3 in the embodiments shown in figures 1 and 2 are shaped approximately as a square. Since the contours and the layout of the cross-flow regions 4 and 18 / 10 and 12 of plates 2, 3 correspond to each other, this also applies to the contours and the layout of the counter-flow regions 6, 14 of the two plates 2,3.
In the counter-flow regions 6 and 14 the first fluid and the second fluid flow in an opposite or anti-parallel flow direction. The directional changes of the counter-flow channels 7 and 15 provided in the counter-flow regions 6, 14 cause irregularities or turbulences of the flows of the first fluid and of the second fluid, which contributes to an improvement in the heat and/or moisture transfer between the fluids 1, 2.
The general flow direction of fluid 1 in the counter-flow region 6 as well as of fluid 2 in the counter-flow region 14, with the plates 2, 3 shown in figures 1 and 2, occurs at an angle of approximately 45 degrees to the general directions A
and B of fluid 1 and fluid 2, respectively. The counter-flow channels 7 of the counter-flow region 6 of plate 2 are, in the case of plates 2, 3 depicted in figures 1 and 2, inclined by a comparatively small angle, which may be between 5 degrees and 25 degrees, in relation to the counter-flow channels 15 of the counter-flow region 14 of plate 2. This ensures that the mechanical structure of the plate packet forming the cross-flow plate heat and/or moisture exchanger 1 is stable with the distances between plates 2, 3 remaining unchanged even in the area of their counter-flow regions 6, 14. When assembling the plate packet of the above-described cross-flow plate heat and/or moisture exchanger 1 it must be ensured that the entry section associated with the first fluid and the entry section associated with the second fluid

- 11 -are arranged in relation to one another in such a way that the first and the second fluid flow in opposite directions in the counter-flow regions 6, 14.
In the exemplary embodiment shown walls 20 of the flow channels 5 of the first cross-flow region 4 of plate 2, walls 21 of the flow channels 11 of the second cross-flow region 10 of plate 2, walls 21 of the flow channels 13 of the first cross-flow region 12 of plate 3 and walls 23 of flow channels 19 of the second cross-flow region 18 of plate 3 are constructed without interruptions, i.e. in a steady and continuous manner. Interruptions between the said walls, in the case of plates 2, 3 depicted in figures 1 and 2, exist in particular at the transitions between the cross-flow regions 4, 10, 12, 18 and the counter-flow regions 6, 14.
Where more turbulent flow conditions are desired or necessary in the cross-flow regions 4, 10, 12, 18, the walls of flow channels 5, 11, 13, 19 may, of course, also have interruptions.

Claims

- 12 -

1. A cross-flow plate heat and/or moisture exchanger having plates (2, 3) which are arranged above, below or next to one another and form alternating flow passages for a first and a second fluid, characterised in that each plate (2, 3) has a first cross-flow region (4, 12), a counter-flow region (6, 14) following the first cross-flow region (4, 12) in flow direction and a second cross-flow region (10, 18) following the counter-flow region (6, 14) in flow direction, in that the cross-flow regions (4, 10, 12, 18) of neighbouring plates (2, 3) form flow channels (5, 11, 13, 19) running approximately perpendicular to one another, in that the counter-flow regions (6, 14) of neighbouring plates (2, 3) form counter-flow channels (7, 15) running approximately parallel to one another, in that the first or second cross-flow region (4, 10) of each plate (2) in terms of its dimensions corresponds to the second or first cross-flow region (18, 12) of each neighbouring plate (3) and is arranged above, below or next to the same, and in that the counter-flow region (6) of each plate (2) in terms of its dimensions corresponds to the counter-flow region (14) of each neighbouring plate (3) and is arranged above, below or next to the same.

2. The cross-flow plate heat and/or moisture exchanger according to claim 1, in which counter-flow channels (7) of the counter-flow region of each plate (2) extend at a slight incline, preferably of 5 degrees to 25 degrees, to the counter-flow channels (15) of the counter-flow region (14) of each neighbouring plate (3).

3. The cross-flow plate heat and/or moisture exchanger according to claim 1 or 2, in which the direction of counter-flow channels (7, 15) of the counter-flow regions (6, 14) of the plates (2, 3) changes.

4. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 3, the plates (2, 3) of which are shaped as a square or a rectangle.

5. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 4, in which the counter-flow regions (6, 14) of each plate (2, 3) are shaped approximately oval or elliptical and extend between two opposite corners (8, 9; 16, 17) of the plate (2, 3).

6. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 5, in which the general flow direction (A, B) of the two fluids separated from each other by the plates (2, 3) through the cross-flow plate heat and/or moisture exchanger (1) is chosen such that the two fluids flow through the counter-flow regions (6, 14) of the cross-flow plate heat and/or moisture exchanger (1) in counter direction.

7. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 6, in which walls (20, 21, 22, 23) of the flow channels (5, 11, 13, 19) of the cross-flow regions (4, 10, 12, 18), which are arranged between the plates (2, 3), are formed in a steady or interruption-free manner.

8. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 6, in which walls arranged between the plates (2, 3), of the flow channels (5, 11, 13, 19) of the cross-flow regions (4, 10, 12, 18) comprise interruptions.

9. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 8, the plates (2, 3) of which are formed of aluminium.

10. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 8, the plates (2, 3) of which are formed of plastic, preferably of a PET
plastic.

11. The cross-flow plate heat and/or moisture exchanger according to one of claims 1 to 8, the plates (2, 3) of which are formed of membrane plates, with a membrane layer, by means of which enthalpy can be transferred between the two fluids, and at least one perforated carrier layer, by means of which a specifiable mechanical strength and a spatial structure can be imparted to the membrane plate and be maintained therein.

12. The cross-flow plate heat and/or moisture exchanger according to claim 11, in which the membrane layer of the plates (2, 3) is formed of a suitable plastic material, preferably a polyurethane or a polymer material.

13. The cross-flow plate heat and/or moisture exchanger according to claim 11 or 12, in which the carrier layer of the plates (2, 3) is formed of a suitable fleece material, preferably a polyester material.