IL300315B1

IL300315B1 - Compact heat exchanger

Info

Publication number: IL300315B1
Application number: IL300315A
Authority: IL
Original assignee: Thyssenkrupp Marine Sys Gmbh; Thyssenkrupp Ag
Priority date: 2020-08-13
Filing date: 2021-08-05
Publication date: 2025-10-01
Also published as: EP4196735B1; IL300315B2; IL300315A; WO2022033947A1; DE102020210310A1; EP4196735C0; EP4196735A1

Description

thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO Compact heat exchanger The invention relates to a heat exchanger of compact construction for applications in which the construction space available is limited and, therefore, efficient heat transfer in a minimal amount of space is necessary.

US 2020/0064075 A1 discloses a counterflow heat exchanger with a spiral construction.

US 10,434,575 B2 discloses a heat exchanger produced by the additive manufacturing method, having a multitude of fluid passages.

US 2019/0063842 A1 discloses a spiral heat exchanger.

US 2019/023703 A1 discloses a spiral heat exchanger.

US 9,657,999 B2 discloses a heat exchanger with alternating channels.

EP 3 410 054 A1 discloses an additively manufactured heat exchanger.

JP 2013-57 426 A discloses a plate heat exchanger.

DE 103 48 803 A1 discloses a plate heat exchanger.

DE 19 08 800 A discloses a plate condenser.

US 2016 / 0 131 443 A1 discloses a heat exchanger.

DE 32 41 842 A1 discloses a heat exchanger in plate form.

DE 11 2015 003 530 T5 discloses a battery cell heat exchanger with gradated heat transfer area. thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO DE 10 2017 107 577 A1 discloses an energy system.

While round, spiral heat exchangers have been found to be very efficient in recent times, these lose out in areas with extremely high integration density, for example on board a submarine, where round components often cannot be integrated into an overall system in such a space-saving manner.

It is an object of the invention to provide a heat exchanger that has good integratability with high efficiency in areas with high integration density and low availability of space.

This object is achieved by a heat exchanger having the features specified in claim 1. Advantageous developments will be apparent from the dependent claims, the description that follows, and the drawings.

The heat exchanger of the invention is designed as a plate heat exchanger. The plate heat exchanger has dividing walls. The dividing walls divide regions for a gaseous heatreleasing medium and a heat-absorbing heat exchange fluid, especially by a heatabsorbing cooling fluid or by a heat-releasing stream of hot water, more preferably by a heat-absorbing cooling fluid. The heat exchanger has first regions between the dividing walls for a gaseous heat-releasing medium and second regions between the dividing walls for a heat exchange fluid, wherein the first regions and the second regions are separated by a multitude of dividing walls. A multitude of dividing walls is preferably 5 to 200 dividing walls, more preferably 20 to 50 dividing walls. First regions and second regions are arranged alternately between every two adjacent dividing walls. Thus, each heat-releasing region adjoins a heat-absorbing region, separated by a dividing wall. With the exception of the two outermost regions, each region bounds either side of the corresponding region, such that optimal heat transfer is possible. The heat exchanger has a heat exchange fluid inlet and a heat exchange fluid outlet. A heat exchange fluid distribution region is disposed between the heat exchange fluid inlet and the second regions. The gaseous medium flows through the heat exchanger preferably from the bottom upward; in this case, the heat exchange fluid flows further preferably through the heat exchanger from the top downward. This particularly preferred case is thus that of a thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO countercurrent heat exchanger through which the flow passes from the bottom upward. The heat exchange fluid inlet is disposed laterally at the upper edge of the heat exchanger.

The openings between the connecting regions and the second regions are of different size. The size of the openings is adjusted here such that the same amount of heat exchange fluid flows into each second region in the same period of time. The openings here are preferably all of the same width; the different size of the openings is preferably achieved via the length of the openings. The centers of all openings preferably lie on one line; the increase or decrease in length is thus preferably symmetric with respect to the center. The openings preferably also have a constant width over the length, with the ends preferably being rounded, preferably semicircular, or corresponding to the shape of the upper half of a droplet. More preferably, the rounded ends are semicircular.

The different size of the openings thus achieves compensation of differences in flow that exist in the heat exchange fluid distribution region, or homogenization of the flow rate. In areas in which the flow toward the openings is greater, the openings are made smaller; in areas in which the flow toward the openings is weaker, these are enlarged. In practical terms, this can be done theoretically by conducting a simulation of the flow until the flow through the openings into the second regions is equal. Alternatively, the adaptation can be done practically, for example in that at first only very small openings are manufactured and then, after a measurement of the amounts of fluid flowing, there is an increase in size of the openings through which less fluid is passing.

One of the most important challenges for achievement of high efficiency is that uniform distribution of the heat exchange fluid and hence very optimal heat transfer is possible at all points. Therefore, specifically maximum uniformity of distribution of the heat exchange fluid between the second regions is one of the key factors for efficient and space-saving heat transfer. thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO Design as a plate heat exchanger, on account of the construction shape, enables very good integration into further systems, for example a fuel cell device, and is thus especially suitable for use in highly integrated regions.

In a further embodiment of the invention, the heat exchange fluid distribution region divides the heat exchange fluid stream into a first substream and a second substream, with the first substream and the second substream being guided laterally in opposite directions. In flow direction of the heat exchange fluid, one substream is thus deflected to the right (+75° to 90°) and the other to the left (-75° to 90°). This can be effected, for example, by a deflecting plate positioned in the inflow. The deflecting plate preferably has at least half the width of the heat exchange fluid inlet. This division into two substreams already achieves a first homogenization, since each substream has to be distributed uniformly only over half of the second regions. The heat exchange fluid distribution region has at least a first connecting region and a second connecting region, wherein the first connecting region guides the heat exchange fluid from the first substream and the second connecting region guides the heat exchange fluid from the second substream into the second regions. The first connecting region and the second connecting region are then adjoined by the openings through which the heat exchange fluid passes from the connecting regions into the second regions. At the same time, the space in the first connecting region serves to uniformly distribute the heat exchange fluid entering from the first substream and to compensate as far as possible for differences in flow. Analogously, the space in the second connecting region serves to uniformly distribute the heat exchange fluid entering from the second substream and to compensate as far as possible for differences in flow.

In a further embodiment of the invention, at least a first flow body is disposed between the first substream and the first connecting region, and at least a second flow body is disposed between the second substream and the second connecting region. A flow body serves to divide and to deflect the fluid stream. For example and with preference, at least two first flow bodies are disposed between the first substream and the first connecting region, and at least two second flow bodies are disposed between the second substream and the second connecting region. The flow bodies and the wall of the heat exchange thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO fluid distribution region are preferably arranged such that the flow of the heat exchange fluid is deflected at least twice between the inlet into the heat exchange fluid distribution region and the connecting regions, i.e. cannot flow directly to the connecting regions. The arrangement of the flow bodies enables further division and better distribution of the heat exchange fluid stream. More preferably, three first flow bodies are disposed between the first substream and the first connecting region, and three second flow bodies are disposed between the second substream and the second connecting region. This enables further division and better distribution of the heat exchange fluid stream. More preferably, at least one of the flow bodies deflects the flow by 120° to 180°. As a result, the flow, after division into the substreams, is deflected back again in the direction of the inlet opening and is distributed better over the entire width.

More preferably, the flow bodies are arranged in such a way that these each generate at least one connecting region substream and deflect in a directed manner, such that the sum total of the connecting region substreams results in maximum uniformity of flow toward the opening.

More preferably, two connecting region substreams in each connecting region are aligned such that these each flow toward the opposite outermost openings.

More preferably, the shape and position of the flow bodies are matched to the size of the openings. More preferably, there is joint optimization of the shape, size and position of the flow bodies simultaneously together with the optimization of the size of the individual openings with the aid of a flow simulation. Simulation is preferred here since a subsequent change in the flow bodies is possible with extreme complexity and difficulty and less accuracy.

In a further embodiment of the invention, the heat exchange fluid inlet is disposed in the middle at the upper edge of the heat exchanger.

In a further embodiment of the invention, the first substream and the first connecting region run parallel alongside one another, and the second substream and the second thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO connecting region run parallel alongside one another. This enables a particularly compact design. Overall, this achieves a very compact heat exchange fluid distribution region, which is preferably 8 to 15 times as broad as the height thereof in flow direction.

In a further embodiment of the invention, the first connecting region and the second connecting region are connected directly to one another for fluidic purposes. The two connecting regions may also merge entirely into one another.

In a further embodiment of the invention, the second regions have at least three essentially horizontal deflecting walls, where the deflecting walls extend over 50% to 85% of the width of the second regions. The uppermost deflecting wall is on the side of the heat exchange fluid distribution region, and the deflecting walls begin alternately from the opposite sides at the outer walls of the second regions, so as to result in a looping flow through the second region for the heat exchange fluid. Corner elements are disposed between each deflecting wall and the outer walls of the second region, wherein the angle between the corner element and the deflecting wall is not more than 45° and the angle between the corner element and the outer wall is not more than 45°.

If the corner element is in a triangular shape, the corner element is preferably an equilateral triangle having two angles of exactly 45° and one angle of 90°.

Rather than flat surfaces at a fixed angle, for example 45°, relative to one another, it is of course also possible here and hereinafter for the person skilled in the art to use rounded transitions that avoid corresponding angles, such that powder residues are removable easily and completely. The use of flat surfaces at a fixed angle is merely the simplest and easily comprehensible embodiment.

Horizontal is level if the heat exchanger is disposed on a flat surface. What is meant by essentially horizontal is an arrangement deviating from the horizontal by not more than ± 15°, preferably by not more than ± 10°, preferably by not more than ± 5°. thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO The use of the corner elements has two technical benefits. Firstly, the avoidance of relatively large angles avoids formation of regions from which powder disposed in the interior in the case of production by means of additive manufacturing methods is not removable. Secondly, dead regions for flow purposes are thus avoided.

In a further embodiment of the invention, the heat exchange fluid inlet has a dropletshaped cross section. This also serves to achieve elevated stability in this region in the case of manufacture by means of additive manufacturing techniques, especially during the manufacturing process.

In a further embodiment of the invention, the heat exchange fluid outlet has a dropletshaped cross section. This also serves to achieve elevated stability in this region in the case of manufacture by means of additive manufacturing techniques, especially during the manufacturing process.

In a further embodiment of the invention, the first regions have baffle plates, wherein the baffle plates are arranged at right angles to the dividing walls. They thus project into the first region and perturb the gas flowing through the first region. The baffle plates are spaced apart from one another. Moreover, the baffle plates are arranged one on top of another in a zigzag and the zigzag rows of the baffle plates are arranged alongside one another. The distances between the zigzag rows are chosen such that there is specifically no resultant flow line of the gas from the inlet to the outlet. The side walls of the baffle plates have an angle with the dividing wall of not more than 45°.

The baffle plates firstly have the effect that the flow of the gaseous heat-releasing medium is slightly extended and hence the contact area is improved, as a result of which condensate forms more easily and can be separated more easily out of the gas phase. Secondly, the baffle plates slow the flow, extend the flow pathway and hence promote better heat exchange. In particular, the ends of the baffle plates also achieve enhanced mixing of the gas stream, which minimizes flow channels of gas that flows through the heat exchanger virtually without contact with heat-exchanging surfaces, and hence increases the heat exchange effect. Secondly, the baffle plates enable downward thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO removal of water separated out in the course of cooling of the gaseous medium along the baffle plates.

The baffle plates preferably have an angle to the horizontal of 10° to 30°, with departure of baffle plates arranged one on top of another from the vertical in opposite directions.

The angle of not more than 45° between baffle plate and dividing wall leads firstly to an optimal manufacturing opportunity by the additive manufacturing process, especially optimal removal of powder residues. Secondly, the geometry is found to be positive for removal of condensed water.

In a further embodiment of the invention, the baffle plates are each arranged in pairs opposite one another on the opposite dividing walls, with the opposite baffle plates connected to one another in the middle between the dividing walls. Mutually opposite dividing walls that surround a common gas region are thus preferably geometric mirror images of one another, with the mirror plane more preferably running in the middle between the dividing walls and parallel thereto. These connections, as well as optimized conduction of gas and optimized removal of condensate, also increase the mechanical stability of the heat exchanger.

In a further embodiment of the invention, the gaseous heat-releasing medium is moisture- saturated, such that there is condensation of water during the cooling in the heat exchanger. Thus, the condensate flows in the opposite direction from the flow direction of the gaseous medium. This arrangement makes it possible to dispense with a downstream water separator, which reduces the amount of space required overall.

In a further embodiment of the invention, the heat exchanger has a rectangular basic shape. This is for integration into highly integrated regions, for example a fuel cell device on board a submarine.

In a further aspect, the invention relates to a process for producing a heat exchanger of the invention by means of additive manufacturing techniques. The high complexity and thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO intricate construction can be produced efficiently specifically by means of additive manufacturing techniques.

In a further aspect, the invention relates to a recirculation fuel cell device having at least one heat exchanger of the invention. More preferably, the heat exchanger is welded to further constituents of the recirculation fuel cell device. In particular, at least one heat exchanger of the invention is disposed in the recirculation circuit of the recirculation fuel cell device.

In a further aspect, the invention relates to a submarine having a fuel cell device, wherein the fuel cell device includes at least one heat exchanger of the invention. Submarines have extremely high integration density, and so complex devices are usable here too in a viable manner in order to satisfy the demands made with a minimal space requirement.

The heat exchanger of the invention is elucidated in detail hereinafter by a working example shown in the drawings.

Fig. 1 perspective view of the heat exchangerFig. 2 top viewFig. 3 vertical cross section through a first regionFig. 4 enlargementFig. 5 lateral view of a baffle plateFig. 6 vertical cross section through a second regionFig. 7 horizontal section through the heat exchange fluid distribution regionFig. 8 vertical cross section through the openings All figures show a particularly preferred embodiment of a heat exchanger 10 from different views or cross sections.

Fig. 1 shows the perspective outside view of the heat exchanger 10. At the top end 20, the slit-shaped openings of the first regions 50 are apparent. At the side wall 70 are disposed the heat exchange fluid inlet 30 and the heat exchange fluid outlet 40. The heat thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO exchange fluid inlet 30 is disposed laterally at the upper edge of the heat exchanger 10, and in the middle.

Fig. 2 shows a top view. In the top view, the first regions 50 and the dividing walls 60 are apparent.

Fig. 3 shows a cross section through the heat exchanger 10 along a first region 50. The gaseous heat-releasing medium flows from the bottom upward, while the heat exchange fluid enters through the heat exchange fluid inlet 30 and then flows from the top downward within the second region 210 (not shown) behind the dividing wall 60, in order then to exit again through the heat exchange fluid outlet 40 at the bottom. The side walls 70 bound the first region 50 laterally. In the interior, baffle plates 80 are arranged alongside one another in zigzag rows. This arrangement of the baffle plates 80 enables, as is apparent in the enlargement of Fig. 4, flow of a condensate on the top side of the baffle plates in each case as condensate flow 100. The vertical separation between the baffle plates allows the condensate to switch in each case "to the other side" and hence to flow away reliably in each case on the top side of the baffle plates 80 without being fluidized again by the gas stream 90. The baffle plates 80 are shown in a lateral view in fig. 5. It is readily apparent here that the baffle plates each have an angle of 45° to the dividing walls 60, which means that powder residues are removable easily and reliably after the additive manufacture. This shape also leads to efficient guiding of the condensate.

Fig. 6 shows a cross section through the heat exchanger 10 along a second region 210; the heat exchange fluid inlet 30 is at the top, and the heat exchange fluid outlet 40 at the bottom. The heat exchange fluid passes via a heat exchange fluid distribution region shown in fig. 7 and fig. 8 through the opening 130 into the second region 210. The deflecting walls 110 guide the heat exchange fluid in a meandering manner through the second region 210. The deflecting walls 100 each alternately adjoin the opposite side walls 70 and are also connected thereto via corner elements 120. The corner elements 120 firstly ensure that no powder residues from additive manufacture remain in the interior. Secondly, these dead volumes avoid in heat exchange fluid stream and hence local overheating. Purely by way of example, it is shown that the corner element 120 does thyssenkrupp Marine Systems GmbHthyssenkrupp AG200426P10WO not have a triangular shape top right, directly beneath the heat exchange fluid distribution region, but rather has two different slopes, such that the angle between deflecting wall 110 and the corner element is below 45°.

Fig. 7 shows the heat exchange fluid distribution region in horizontal section. The heat exchange fluid flows in through the heat exchange fluid inlet 30 and is divided into a first substream 140 and a second substream 150. In order to save space, the substreams 140, 150 run at right angles to the heat exchange fluid inlet 30 and hence parallel to the side wall 70. The heat exchange fluid stream is from the first substream 140 by means of three first flow bodies 180 into the first connecting region 160. On the other side, the heat exchange fluid stream from the second substream 150 is correspondingly guided by means of three second flow bodies 190 into the second connecting region 170. This achieves very substantial homogenization of the heat exchange fluid stream, but complete homogenization is extremely difficult. In order to further compensate for these differences and hence to achieve the effect that equal amounts of heat exchange fluid flow through all the second regions 210, the openings 130 are of different size, as is readily apparent in the cross section in fig. 8. The efficacy is shown in that a test results in a uniformly high waterline, the heat exchange fluid pressure is thus at the same level everywhere, and hence so is the amount of heat exchange fluid flowing through the second regions 210.

List of reference numeralsheat exchangertop endheat exchange fluid inletheat exchange fluid outletfirst regiondividing wallside wallbaffle plategas stream100 condensate flow 200426P10WOthyssenkrupp Marine Systems GmbHthyssenkrupp AG 110120130140150160170180190200210 deflecting wallcorner elementopeningfirst substreamsecond substreamfirst connecting regionsecond connecting region first flow bodysecond flow body waterlinesecond region

Claims

1. 300315/ 0292452645- Claims 1. A heat exchanger, wherein the heat exchanger is designed as a plate heat exchanger, wherein the heat exchanger has dividing walls, wherein the heat exchanger has first regions between the dividing walls for a gaseous heat-releasing medium and second regions between the dividing walls for a heat-absorbing heat exchange fluid, wherein the first regions and the second regions are separated by a multitude of dividing walls, wherein alternating first regions and second regions are arranged between every two adjacent dividing walls, wherein the heat exchanger has a heat exchange fluid inlet and a heat exchange fluid outlet, wherein a heat exchange fluid distribution region is disposed between the heat exchange fluid inlet and the second regions, wherein the gaseous medium flows through the heat exchanger from the bottom upward, wherein the heat exchange fluid flows through the heat exchanger from the top downward, wherein the heat exchange fluid inlet is disposed laterally at the upper edge of the heat exchanger, characterized in that the heat exchange fluid distribution region has at least a first connecting region and a second connecting region, wherein the heat exchange fluid distribution region guides the heat exchange fluid stream through multiple openings into the second regions, wherein the openings between the connecting regions and the second regions are of different size, wherein the size of the openings is adjusted such that the same amount of heat exchange fluid flows into each second region in the same period of time, wherein the heat exchange fluid inlet is disposed in the middle at the upper edge of the heat exchanger.

2. The heat exchanger as claimed in claim 1, characterized in that the heat exchange fluid distribution region divides the heat exchange fluid stream into a first substream and a second substream, wherein the first substream and the second substream are guided laterally in opposite directions, wherein the first connecting region guides the heat exchange fluid from the first substream and the second connecting region guides the heat exchange fluid from the second substream through multiple openings into the second regions.

3. The heat exchanger as claimed in either of the preceding claims, characterized in that at least a first flow body is disposed between the first substream and the 300315/ 0292452645- first connecting region, with at least a second flow body disposed between the second substream and the second connecting region.

4. The heat exchanger as claimed in any one of the preceding claims, characterized in that the second regions have at least three essentially horizontal deflecting walls, wherein the deflecting walls extend over 50% to 85% of the width of the second regions, wherein the uppermost deflecting wall is on the side of the heat exchange fluid distribution region, wherein the deflecting walls commence in an alternating manner from the opposite sides of the second regions, so as to result in a looping flow through the second region for the heat exchange fluid, with corner elements disposed between each deflecting wall and the outer walls of the second region, wherein the angle between the corner element and the deflecting wall is not more than 45°, wherein the angle between the corner element and the outer wall is not more than 45°.

5. The heat exchanger as claimed in any one of the preceding claims, characterized in that the heat exchange fluid inlet has a droplet-shaped cross section.

6. The heat exchanger as claimed in any one of the preceding claims, characterized in that the first regions have baffle plates, wherein the baffle plates are arranged at right angles to the dividing walls, wherein the baffle plates are spaced apart from one another, wherein the baffle plates are arranged one on top of another in a zigzag, wherein the zigzag rows of the baffle plates are arranged alongside one another, wherein the side walls of the baffle plates have an angle with the dividing wall of not more than 45°.

7. The heat exchanger as claimed in claim 6, characterized in that the baffle plates are each arranged in pairs opposite one another on the opposite dividing walls, wherein the opposite baffle plates are connected to one another in the middle between the dividing walls.

8. A process for producing a heat exchanger as claimed in any one of the preceding claims by means of additive manufacturing techniques. 300315/ 0292452645-

9. A submarine having a fuel cell device, wherein the fuel cell device includes at least one heat exchanger as claimed in any one of claims 1 to 7.