DE102015115054A1 - Thermoelectric generator device - Google Patents

Abstract

The invention relates to a thermoelectric generator device comprising a thermoelectric device (17), and a heat transfer device having at least one heat exchanger (20) and at least one cold heat exchanger (16; 24) in thermal contact with the thermoelectric device (17) in which at least the at least one hot heat exchanger (20) is provided for flowing through with a gas as heat transfer fluid, and wherein the at least one hot heat exchanger (20) and / or the at least one cold heat exchanger (16; 24) has a rib structure (52) with flow channels (70 ), and flow channels (70) between ribs (72) of the rib structure (52) are formed, wherein flow channels (70) have a width (B) in a width direction (74) of at most 0.75 mm, wherein the width direction (74 ) is a spacing direction between spaced ribs (72).

Description

The invention relates to a thermoelectric generator apparatus, comprising a thermoelectric device, and a heat transfer device with at least one hot heat exchanger and at least one cold heat exchanger, which are in thermal contact with the thermoelectric device, wherein at least the at least one hot heat exchanger is provided for flow with a gas as the heat transfer fluid , and wherein the at least one hot heat exchanger and / or the at least one cold heat exchanger has a rib structure with flow channels, and flow channels are formed between ribs of the rib structure.

In the unpublished German Patent Application No. 10 2013 112 911.0 of November 22, 2013, the same applicant discloses a thermoelectric generator apparatus comprising a housing and at least one combination with the components of first cold heat exchanger, second cold heat exchanger, first thermoelectric layer, second thermoelectric layer and hot heat exchanger, wherein in the at least one combination of the heat exchangers between the the first thermoelectric layer and the second thermoelectric layer is disposed, the first cold heat exchanger to the first thermoelectric layer and the second cold heat exchanger is disposed on the second thermoelectric layer, and wherein the at least one combination is positioned in the housing, characterized in that a first inner side a first wall of the housing is in direct planar mechanical contact with the first cold heat exchanger of the at least one combination or the first wall is a wall of the first Kaltwärmeübertra gers forms that one of the first inner side opposite second inner side of a second wall of the housing is in direct planar mechanical contact with the second cold heat exchanger of at least one combination or another combination or forms a wall of the second cold heat exchanger, and that the housing by positive engagement at least an operating point or operating point range of the thermoelectric generator device provides a contact pressure, which braces the components of the at least one combination against each other and clamped in the housing.

From the DE 10 2010 042 603 A1 a thermoelectric generator apparatus is known, comprising a fluid-tight first housing, at least one fluid-tight second housing, which is arranged on the first housing, wherein between the first housing and the at least one second housing, a first medium flow is guided, a fluid-tight third housing which on the at least one second housing is arranged, wherein in the third housing, a second medium flow is guided, and at least one thermoelectric module, which is arranged between the at least one second housing and the third housing and having a first side in thermal contact with the second housing is standing and with a second side in thermal contact with the third housing.

From the DE 10 2007 063 171 A1 a thermoelectric generator with at least one thermoelectric module is known, wherein a connecting device is provided, through which a transverse to at least one contact surface of a thermoelectric module directed clamping force can be generated.

From the DE 10 2007 063 173 A1 is a thermoelectric generator having at least one heat sink, at least one heat source, wherein the sum of the number of heat sinks and the number of heat sources is at least three, wherein the at least one heat source has at least one flow passage for flowing through a fluid, and at least two thermoelectric Modules, wherein in each case between a heat sink and a heat source, at least one thermoelectric module is arranged known.

From the DE 10 2007 063 196 A1 a thermoelectric generator with a connecting device is known, which comprises at least one under tension clamping element which surrounds a stack at least in sections and exerts an at least approximately parallel to the stacking axis compressive force on the stack.

From the DE 10 2009 013 535 A1 a thermoelectric device for generating electrical energy from heat is known, which has a holding structure, which is designed to guide a hot and a cold medium and for holding a thermoelectric module.

From the DE 10 2008 005 334 A1 a thermoelectric generator for an exhaust stream is known, which is connected to an exhaust passage, wherein at least one thermoelectric conversion element is arranged, which converts thermal energy into electrical energy and a heat exchanger element which at least partially disposed on a surface of the thermoelectric conversion element and at least partially in the exhaust duct is, wherein at least one heat pipe is arranged in the exhaust duct, which is the thermal energy the exhaust gas stream to the surface of the thermoelectric conversion element passes.

From the DE 10 2010 001 417 A1 a heat exchanger for thermoelectric generators is known, which has at least two channels for a cooling medium and at least one channel for a heating medium, wherein the at least one channel for the heating medium in the interior is equipped with ribs.

From the KR 20120112185 For example, a thermoelectric conversion unit and a manufacturing method are known.

The invention has for its object to provide a thermoelectric generator device of the type mentioned, in which a homogenization of a heat flow between the hot heat exchanger and the cold heat exchanger takes place in a longitudinal direction and an increased efficiency is achieved.

This object is achieved in the above-mentioned thermoelectric generator device according to the invention in that flow channels have a width in a width direction of at most 0.75 mm, wherein the width direction is a distance direction between spaced ribs.

It has been found that, in order to achieve a high power density in a thermoelectric generator device, it is favorable when there are narrow flow channels, that is to say narrow rib spacings of at most 0.75 mm and in particular less than 0.5 mm.

Furthermore, it is favorable to achieve a high power density when the flow channels have a high height. According to the invention, it is provided, in particular, that flow channels have a height in a height direction of at least 11 mm and preferably at least 13 mm, wherein the height direction is oriented transversely to the width direction and transverse to a main flow direction of heat transfer fluid.

In particular, the thermoelectric device has at least one thermoelectric layer with a first end and a second end opposite the first end, the first end facing an input for heat transfer fluid of the at least one hot heat exchanger and / or the at least one cold heat exchanger, and the second end a Output for heat transfer fluid of at least one hot heat exchanger and / or the at least one cold heat exchanger is facing. It can thereby achieve an effective flow.

In particular, a spacing direction between the first end and the second end of the at least one thermoelectric layer is parallel to a main flow direction for heat transfer fluid in the at least one hot heat exchanger and / or the at least one cold heat exchanger. This makes it possible to achieve a high power density.

It has proven favorable if the thermoelectric generator device is "short" in terms of its main active components. In particular, a distance between the first and the second end of the at least one thermoelectric layer is in the range between 30 mm and 70 mm. As a result, an effective equalization of the heat flow density of the main flow direction can be achieved. This in turn allows a high efficiency can be achieved.

For equalization of the heat flow density, it is favorable if, at least in the at least one hot heat exchanger, a first end of the rib structure, which faces the input, is spaced from the first end of the at least one thermoelectric layer in a main flow direction, wherein in the main flow direction the first end the at least one thermoelectric layer is located in front of the first end of the rib structure. As a result, a certain amount of "delayed" heat is transferred to the at least one thermoelectric layer. This leads to a homogenization. A homogenization of the heat flux density is particularly useful with respect to the "source", namely the at least one hot heat exchanger, since there the strongest temperature drop arises. The same measures can also be performed for the at least one cold heat exchanger, wherein usually the temperature drop in the longitudinal direction of the cold heat exchanger (as a sink for the heat flow) is negligible.

It has been shown that it is favorable if a distance between the first end of the at least one thermoelectric layer and the first end of the rib structure lies in the range between 1 mm and 3 mm.

It has also been found favorable for equalization of the heat flux density in the longitudinal direction, when a second end of the rib structure, which faces the exit, at least at the at least one hot heat exchanger relative to the second end of the at least one thermoelectric layer is spaced, wherein the second end the at least one thermoelectric layer is located in front of the second end of the fin structure with respect to a main flow direction of heat transfer fluid. It gets on it still transfer a heat during operation to the at least one thermoelectric layer in the region of the output.

It has proved favorable if a distance between the second end of the at least one thermoelectric layer and the second end of the rib structure is in the range between 2 mm and 10 mm.

It is favorable if, in a direction transverse to a direction between the first end and the second end, the thermoelectric device is narrower than the rib structure, wherein in particular the rib structure with a projection in the range between 1 mm and 5 mm protrudes beyond the thermoelectric device. In particular, the rib structure protrudes with a projection both in the longitudinal direction (in a direction between the first end and the second end of the at least one thermoelectric layer) and in the transverse direction to this longitudinal direction with a projection over the rib structure.

For equalization of the heat flow density in the longitudinal direction (parallel to a main flow direction of heat transfer fluid), it is favorable, in particular for the at least one hot heat exchanger, if the rib structure facing an input for heat transfer fluid has a region which is free of ribs. The rib-free area provides a "non-contact area" for heat transfer near the entrance. It has been found that such a rib-free area leads to a homogenization in the longitudinal direction and thus to an increased efficiency.

In particular, the rib-free region is mirror-symmetrical to an axis. This results in an effective homogenization.

In one embodiment, it is contemplated that the rib-free region has a length that is between 20% and 50% of a total length of the rib structure between a first end and a second end of the rib structure, and more preferably between 30% and 50% and preferably between 30 % and 45% of the total length. This results in an effective homogenization with a corresponding positive influence on the efficiency of the thermoelectric generator device.

It has also been found to be advantageous if the rib-free region has a width which decreases from a first end of the rib structure to a second end of the rib structure. The rib-free area thus decreases in size from the first end to the second end.

In particular, the width decreases monotonously.

It has also proven to be favorable that the rib-free region has a curved boundary line. It can thereby achieve an effective homogenization.

In an advantageous embodiment, it is provided that the fin-free region has a boundary line according to a logarithmic function.

It can be provided that at least one support strut is arranged on the rib structure in the rib-free region. Above all, the support strut has a mechanical support function for increasing the rigidity of the rib structure in this area. It has no special thermal function.

In one embodiment, at least one support strut is oriented transversely to a longitudinal direction of flow channels. This can increase the rigidity.

It is also advantageous for equalizing the heat flux density in a longitudinal direction when the fin structure has a first region in which flow channels are arranged parallel to a main flow direction, and has a second region which adjoins the first region, and in which the rib structure in Compared to the first region has an increased heat absorption capacity of the heat transfer fluid. It is thereby increased toward the output, the heat-emitting ability, that is, the heat flow density is increased. There is provided in the region where the temperature of the heat transfer fluid drops, for a more effective heat coupling in order to increase the heat flux density in the second region.

It can be provided that the flow channels are arranged in the second region parallel to each other. Such flow channels can then be produced in a simple manner.

The increased heat-absorbing capacity and the resulting increased heat-releasability in the second region may be made by guiding flow channels and / or by material selection of ribs.

In one embodiment, the fin structure in the second region has fin regions with a transverse orientation to the main flow direction. It increases the contact area for heat transfer fluid in the second area compared to the first area and thereby the Heat-absorbing capacity (and consequently the heat-releasing ability) increased.

In one embodiment, the ribs in the second region have a wave structure. Flow channels in the second region are then formed wave-shaped. Wave crests and wave troughs form rib areas with transverse orientation.

It is alternatively or additionally possible that the rib structure in the second region is made of the material which has a higher thermal conductivity in the first region compared to a material of the rib structure. As a result, a homogenization of the heat flow density in the longitudinal direction can be achieved.

It has proven to be advantageous if the second region starts at at least 30% of a total length of the rib structure between a first end and a second end of the rib structure. This can achieve an effective homogenization.

It may be provided that the first region lies at least partially against a rib-free region of the rib structure. It is possible that the corresponding rib-free area lies only at the first area. It is also possible for the rib-free area to protrude into the second area, but a part of the rib-free area then lies on the first area.

It is particularly advantageous if the rib structure is made of a metallic material. This results in an effective heat-absorbing capacity and effective heat-releasability. This makes it possible to achieve a high heat flow density between the at least one hot heat exchanger and the at least one cold heat exchanger through the thermoelectric device.

It has proved to be advantageous if the rib structure is made of nickel and in particular pure nickel.

It is also possible that the rib structure is made of stainless steel.

A simple structural design results when the fin structure has a plurality of plates on which channels are formed, the plates are oriented parallel to each other, adjacent plates abut each other, and flow channels are formed via channels in one plate and plate regions of an adjacent plate. The overall rib structure can thereby be built from the plates, wherein separate flow channels can be produced in a simple manner. The support of adjacent plates together leads to the formation of corresponding flow channels. Furthermore, this achieves a high mechanical stability.

In principle, it is possible for the panels to be made in a composite, which is then folded into a sheet package. From a manufacturing point of view, it is advantageous if the plates are separate individual plates. This results in a simple manufacturability.

It is particularly advantageous if the plates are designed as equal plates, that is, a plurality of plates and in particular all plates are formed the same.

It is also advantageous if a plate comprises at least one positioning element and / or at least one support element for one or more further plates. This makes it easy to produce a plate package with appropriate orientation and support.

In one embodiment, at least one opening is provided as a positioning element. This opening is arranged, for example, on or in the vicinity of a rib-free area. Through this opening plates can be aligned.

It is particularly advantageous if a plate pack is provided in which a plurality of plates are connected in a package and in particular clamped together. The rib structure for the at least one hot heat exchanger and / or the at least one cold heat exchanger can thereby be produced in a simple manner.

In one embodiment, at least one holding element is provided, which is arranged on the plate pack, wherein in particular at least two holding elements are provided, and wherein the plate pack is held on a housing via the at least one holding element. This makes it easy to position the rib structure in the housing. The housing itself is advantageously designed as a tube, which is traversed by heat transfer fluid, which is in particular a gas and in particular an exhaust gas.

In one embodiment, the housing has a first shell and a second shell, between which the at least one hot heat exchanger is arranged. As a result, the at least one hot heat exchanger can be produced in a simple manner.

In one embodiment, a housing is provided. Furthermore, at least one combination with the components of the first cold heat exchanger, second cold heat exchanger, first thermoelectric layer, second thermoelectric layer and hot heat exchanger is provided, is arranged in the at least one combination of the hot heat exchanger between the first thermoelectric layer and the second thermoelectric layer, the first cold heat exchanger the first thermoelectric layer and the second cold heat exchanger is disposed on the second thermoelectric layer, and wherein the at least one combination is positioned in the housing. This results in a compact construction with a plurality of thermoelectric layers and correspondingly usable electric current is produced.

It is advantageous if a first inner side of a first wall of the housing is in direct planar mechanical contact with the first cold heat exchanger of the at least one combination or the first wall forms a wall of the first Kaltwärmeübertragers that one of the first inner side opposite second inner side of a second wall the housing is in direct planar mechanical contact with the second cold heat exchanger of the at least one combination or a further combination or forms a wall of the second cold heat exchanger, and that the housing by positive engagement at least at an operating point or operating point range of the thermoelectric generator device provides a contact pressure, which the components the at least one combination braced against each other and clamped in the housing. It parasitic heat flows are minimized because no flow space between the housing and the first cold heat exchanger and the second cold heat exchanger is present. A corresponding thermoelectric generator device of this embodiment is in the non-prepublished German application no. 10 2013 112 911.0 discloses, to which express and complete reference is made.

The following description of preferred embodiments is used in conjunction with the drawings for further explanation of the invention.

Show it:

1 (a) a schematic representation of an embodiment of a thermoelectric generator device according to the invention in an exploded view;

1 (b) the thermoelectric generator device according to 1 (a) in the assembled state;

2 a perspective view of an embodiment of a Heißwärmeübertragers;

3 the hot heat exchanger according to 2 in a section in the sectional plane A according to 2 ;

4 the hot heat exchanger according to 2 in a section in the sectional plane B according to 2 ;

5 a plan view of the sectional plane B of the hot heat exchanger according to 2 ;

6 (a) an embodiment of a plate of a rib structure of the Heißwärmeübertragers according to 2 ;

6 (b) a plan view of a plate pack (in the direction B according to FIG 4 );

7 (a) an embodiment of a rib structure with a rib-free area;

7 (b) Another embodiment of a rib structure with a rib-free area;

8th a partial view of an embodiment of a rib structure;

9 schematically the influence of temperature on a thermoelectric layer using a rib structure according to 8th depending on the position in a main flow direction as compared with a rib structure as shown in FIG 10 is shown;

10 a comparative rib structure; and

11 schematically the structure of ribs in the rib structure according to 8th ,

An embodiment of a thermoelectric generator device according to the invention, which in the 1 (a) and 1 (b) is shown schematically and there with 10 is designated comprises a housing 12 , The housing 12 takes a combination 14 on, which has the following components: a first cold heat exchanger 16 , a first thermoelectric layer 18 a thermoelectric device 17 , a heat exchanger 20 , a second thermoelectric layer 22 the thermoelectric device 17 , and a second cold heat exchanger 24 ,

The combination 14 is constructed as a sandwich structure. The heat exchanger 20 lies between the first thermoelectric layer 18 and the second thermoelectric layer 22 , wherein the first thermoelectric layer 18 the Hot heat exchanger 20 thermally contacted, and the second thermoelectric layer 22 the hot heat exchanger 20 thermally contacted.

The heat exchanger 20 includes a housing 26 , which is designed as a tube. The first thermoelectric layer 18 and the second thermoelectric layer 22 are on the case 26 on opposite flat sides 28a . 28b positioned.

The combination of components from the first thermoelectric layer 18 , Heat exchangers 20 and second thermoelectric layer 22 lies between the first cold heat exchanger 16 and the second cold heat exchanger 24 , The first cold heat exchanger 16 thermally contacts the first thermoelectric layer 18 and the second cold heat exchanger 24 thermally contacts the second thermoelectric layer 22 ,

The housing 26 has a first wall 30 and a second wall opposite the first wall 32 , At the first wall 30 is the flat side 28a educated. At the second wall 32 is the flat side 28b educated. The first wall 30 and the second wall 32 are over spaced transverse walls 34 and 36 connected with each other.

The first wall 30 and the second wall 32 lie parallel to each other. The transverse walls 34 and 36 are also parallel to each other.

In one embodiment, the flat sides 28a . 28b just. At least at one operating point or operating point range of the thermoelectric generator device 10 in which it is operated in a normal operating condition, and hot medium (and in particular hot gas) the hot heat exchanger 20 flows through, and thereby at the thermoelectric layers 18 . 20 usable electric power is generated, these are flat sides 28a . 28b just trained.

With regard to the further constructional structure of the thermoelectric generator apparatus is on the non-prepublished German Patent Application No. 10 2013 112 911.0 of 22 November 2013 by the same applicant. This document is incorporated by reference in its entirety.

The housing 26 of the heat exchanger 20 In one embodiment, it is double-shelled with a first shell 38 and a second shell 40 which are interconnected.

The heat exchanger 20 has on the case 26 an entrance 42 for (hot) heat transfer fluid, and further has an output 44 on.

Between the entrance 42 and the exit 44 flows through heat transfer fluid, in particular in gaseous form in a main flow direction 46 the hot heat exchanger 20 ,

At the first shell 38 is the first wall 30 with part of the transverse walls 34 and 36 educated. At the second shell 40 is the second wall 32 with part of the transverse walls 34 . 36 educated.

It can be provided that the housing 26 in the area of the entrance 42 a flange 48 having.

It may further be provided that on the housing 26 in the area of the exit 44 a flange 50 is arranged.

In the case 26 is a rib structure 52 arranged, in which flow channels are formed.

In one embodiment, the rib structure is 52 through a plate pack 54 (see. 6 (b) ) a plurality of plates 56 formed (see also 6 (a) ). The plates 56 are in the disk pack 54 oriented parallel to each other. The corresponding plates 56 have opposite longitudinal sides 58a . 58b on. Over the long side 58a the plates are supported 56 on the inside of the first wall 30 from. Over the long side 58b lean against the inside of the second wall 32 from. An alignment of the plates 56 is transverse and in particular perpendicular to the first wall 30 and the second wall 32 of the housing 26 ,

Basically, the plates can 56 be integrally connected to each other and by a folding structure, the plate package 54 be prepared.

In one embodiment ( 6 (a) and (b)) the plates are single parts 56 which are in the plate pack 54 interconnected and in particular are clamped together.

In particular, the plates 56 of the disk pack 54 Common parts, that is, all plates 56 or at least a majority of the plates 56 of the disk pack 54 (possibly with the exception of outer plates) are the same.

The plates 56 have respective support areas 60 on (cf. 6 (b) ) about which neighboring plates 56 ' and 56 '' support each other.

A plate 56 itself has an area 62 on, in which channels 64 (See, for example 8th ) are formed. In particular, one page 66 a plate 56 just trained and on an opposite side 68 are channels 64 educated. At a plate 56 are the channels 64 doing so in a transverse direction to the page 66 or 68 (which a distance direction between the page 66 and the page 68 corresponds) to one side open.

In the plate pack 54 lies the page 66 a plate 56 '' on the side 68 an adjacent plate 56 ' at. As a result, the channels are closed in the mentioned spacing direction and are thus flow channels 70 educated. The flow channels 70 are in the main flow direction 46 flow through.

The channels 64 are there by ribs 72 (See also the 8th and 11 ) limited.

A width B of a flow channel 70 which in a width direction 74 lies, with the width direction 74 a distance direction between adjacent ribs 72 is at most 0.75 mm and preferably at most 0.5 mm.

The flow channels 70 have a height H in a height direction 76 which is at least 11 mm and preferably at least 13 mm. The height direction 76 lies perpendicular to the width direction 74 and transverse and in particular perpendicular to the main flow direction 46 ,

Ribs 72 themselves are in cross section, for example, rectangular or trapezoidal. In a rectangular configuration of ribs 72 have the flow channels 70 over its entire height H in the height direction 76 an equal width. In a trapezoidal configuration, the width varies B. In this case, the average width is at most 0.75 mm.

In an embodiment which is shown schematically in FIG 7 (a) is shown has a plate 56 the area 62 with the channels 64 which are in the plate pack 54 the flow channels 70 make up. The plate 56 and thus the rib structure 52 also has a rib-free area 78 on. In this rib-free area 78 , which starting from the entrance 42 is, are no flow channels 70 formed (with a width B of at most 0.75 mm).

The rib-free area 78 has a width which is in a direction x (longitudinal direction) between the entrance 42 and the exit 44 decreases. In particular, the rib-free area 78 a boundary line 80 which decreases steadily in the direction x and in particular monotonically steadily. The boundary line 80 can be represented as function y (x), wherein the y-axis is perpendicular to the x-axis (as a distance axis between the input 42 and the exit 44 ).

In one embodiment, the boundary line 80 represented by a logarithmic function: y (x) = a + b · ln (1 - x) a and b are parameters. x is less than 1.

The boundary line 80 on a plate is mirror-symmetrical to a mirror axis 82 ,

In a variant of an embodiment ( 7 (b) ) it is envisaged that in the rib-free area 78 support struts 84 are arranged. These are used for mechanical support on the plate 56 and to increase the mechanical stability of the rib structure 52 ,

In one embodiment, struts are 84 provided, which is transverse to a longitudinal direction of flow channels 70 are aligned. They are in particular parallel to the width direction 74 the flow channels 70 educated.

The struts 84 in the rib-free area 78 are arranged and formed so that the heat-absorbing capacity in the rib-free area 78 is significantly lower than in the area 62 with the flow channels 70 and more preferably at most 20% of the heat capacity in the area 62 is.

In one embodiment, the range is 62 the plates 56 in which the flow channels 70 are formed, further divided into a first area 86 and a second area 88 (see. 8th ).

In 10 an example case is shown in which such a subdivision does not occur.

The rib-free area 78 lies at the first area 86 , However, it is possible that the rib-free area 78 not in the second area 88 sticks out or into the second area 88 protrudes.

The first area 86 and the second area 88 are designed so that they differ in their heat absorption capacity in the flow of heat transfer fluid and thereby have different heat release capabilities. The second area 88 is designed so that it faces the first area 86 has an increased heat releasing ability.

In a longitudinal direction 90 the rib structure 52 , which are parallel to the main flow direction 46 is a variation of the heat-absorbing capacity and heat-releasing ability of the rib structure 52 by training the first area 86 and of second area 88 in front. (In the structure, as in 10 is shown schematically, such a variation does not exist.)

The variation in the formation of heat-absorbing properties and heat-dissipating properties between the first region 86 and the second area 88 can be achieved by the material of the rib structure 52 in the second area 88 has a higher thermal conductivity than the material of the rib structure in the first region 86 , Through different choice of material for the rib structure 52 in the respective first area 86 and the second area 88 , and thereby on a plate 56 , one can be in the second area 88 compared to the first area 86 increased heat absorption property and increased heat dissipation property can be achieved.

In an embodiment which is in 8th is shown schematically, the increased heat absorption property and increased heat dissipation property in the second area 88 by appropriate geometric design of the flow channels 70 reached.

In the first area 86 are the flow channels 72 oriented parallel to each other while parallel to the longitudinal direction 90 and in turn at least approximately parallel to the main flow direction 46 oriented.

In the second area 88 , which is located at the first area 86 connects, and in which the flow channels from the first area 86 continue, are the flow channels 70 continue parallel to each other, but no longer parallel to the main flow direction 46 , In the second area 88 have the flow channels 70 Rib areas with a transverse orientation 92 to the main flow direction 46 on. This transverse orientation is achieved, for example, by a wave-shaped formation of ribs in the second region 88 reached. This provides a larger area where heat transfer fluid can flow past. As a result, in turn, the corresponding rib structure in the second area 88 absorb more heat.

The rib structure 52 has a first end 94 which is the entrance 42 is facing. It also has a second end 96 which is the exit 44 assigned. Between the first end 94 and the second end 96 the rib structure extends 52 also related to the main flow direction 46 ,

The plates 56 can do it over the first end 94 and / or the second end 96 extend. The rib structure 52 extends between the first end 94 and the second end 96 in such an area, via the heat to the first thermoelectric layer 18 and the second thermoelectric layer 22 a thermoelectric device 17 is deliverable.

A length of the rib structure between the first end 94 and the second end 96 is L _H (cf. 7 (b) ).

The rib-free area 78 has an end 98 up to which he is starting from the entrance 42 extends. This end 98 defines a length L _{0 of} the rib-free area 78 along the direction x. This length L ₀ is in the range between 20% and 50% of the total length L _H and in particular between 30% and 50% of L _H and preferably between 30% and 45% of L _H.

A transition 100 (see. 8th ) between the first area 86 and the second area 88 the rib structure 52 is at least 30% of the total length L _H. As mentioned above, depending on the training, the rib-free area 78 in the second area 88 protrude or only in or on the first area 86 be arranged.

In one embodiment (see 4 and 5 ) has the thermoelectric device 17 with the first thermoelectric layer 18 and the second thermoelectric layer 22 a first end 102 on which the entrance 42 facing, and a second end 104 on which the exit 44 is facing. Between the first end 102 and the second end 104 extends the respective thermoelectric layer 18 respectively 22 in a length L _T.

The rib structure 52 with her first end 94 is opposite the first end 102 the thermoelectric device 17 added. There is a distance D ₁ between the first end 102 the thermoelectric device 17 and the first end 94 the rib structure 52 in front. This distance D ₁ is such that in the main flow direction 46 (in the direction x) the first end 102 the thermoelectric device 17 before the first end 94 the rib structure 52 lies.

In particular, the distance D _{1 is} in the range between 1 mm and 3 mm.

In one embodiment, it is further provided that the second end 96 the rib structure 52 via the thermoelectric device 17 protrudes, that is, there is a distance D ₂ between the second end 104 the thermoelectric device 17 and the second end 96 the rib structure 52 in front. In the direction x (in the main flow direction 46 ) is the second end 104 the thermoelectric device 17 opposite the rib structure 52 (relative to its second end 96 ) reset.

The distance D ₂ is for example in the range between 2 mm and 10 mm. In one embodiment, the generator device is 10 based on the total length L _{T of} the thermoelectric device 17 relatively short. The total length is in particular in the range between 30 mm and 70 mm.

As already mentioned, the rib structure 52 through the plate pack 54 educated. This is a plurality of plates 56 in the height direction 76 arranged side by side in parallel. This in turn are due to the plates 56 formed flow channels 70 (with first areas 86 and second areas 88 ) and rib-free areas 78 in the height direction 76 arranged side by side (see the 2 to 6 ).

At the second end 96 are the plates 56 outside the rib structure 52 with elements 106 provided, which in particular for positioning the disk pack 54 serve. The Elements 106 are in particular integral with the second area 88 a corresponding plate 56 connected.

The plates 56 of the disk pack 54 are, as already mentioned, with support elements 108 and positioning elements 110 provided to achieve a support and positioning.

In one embodiment, positioning elements include 110 openings 112 in the respective plates. In a plate pack are the openings 112 aligned with each other.

The plate package 54 is for example by clamping plates together 56 produced.

On opposite sides is on the plate pack 54 a holding element 114a and 114b arranged. About this holding element sits the plate package 54 in the case 26 on the corresponding shell 38 respectively 40 ,

For example, the housing has 26 lateral slots on and the plate pack 54 is about the retaining elements 114a . 114b positioned at these slots. In particular, the plate pack 54 in this way, for example, the second shell 40 fixed. This structure can also be used to the first shell 38 concerning the second shell 40 to fix. For example, one of the other shell 38 respectively 40 facing area of the shell 40 respectively 38 connected via a solder connection.

The holding elements 114a . 114b are for example with the plate package 54 welded.

The support elements 108 on the plates 54 can also be designed as spacers. They are channels 116 in the rib-free area 78 formed, which to the flow channels 70 in that area 62 to lead. The channels 116 have it in the width direction 74 and in the height direction 76 larger (and in particular considerably larger) dimensions than the flow channels 70 in that area 62 ,

The rib structure 52 is made of a metallic material.

It has proven to be advantageous if the rib structure is made of pure nickel.

For example, it is also possible that the rib structure 52 made of a stainless steel material.

The thermoelectric generator device 10 works as follows:
The heat exchanger 20 is flowed through with a hot medium. The hot medium serves as a heat transfer fluid. The heat transfer fluid is in particular a gas such as the exhaust gas of an internal combustion engine.

The first cold heat exchanger 16 and the second cold heat exchanger 24 are flowed through by a cooling medium. In particular, there is a cross-flow with respect to the hot heat exchanger 20 in front.

Between the hot heat exchanger 20 and the first cold heat exchanger 16 or the second cold heat exchanger 24 There is a temperature gradient, which is the thermoelectric device 17 at the first thermoelectric layer 18 and the second thermoelectric layer 22 is exposed. Between the hot heat exchanger 20 and the first cold heat exchanger 16 or the second cold heat exchanger 24 During operation, a heat flow is generated. This heat flow is due to thermoelectric modules 118 (see. 4 and 5 ) at. A usable electric current can be generated from this via the Seebeck effect.

The thermoelectric device 17 includes in the first thermoelectric layer 18 and the second thermoelectric layer 22 a plurality of thermoelectric modules 118 , wherein in the corresponding thermoelectric layer 18 respectively 22 the thermoelectric modules 118 are in particular connected in series.

It may be provided that thermoelectric modules 118 are arranged on a separate support or that they are directly on the first wall 30 or the second wall 30 of the housing 26 are arranged.

The thermoelectric elements of thermoelectric modules are in particular bridges, n-conductors and p-conductors.

Due to the inventive design of the Heißwärmeübertragers 20 with the rib structure 52 one obtains a homogenization of the heat flow in the main flow direction 46 (in the direction x). Basically, it is such that a heat transfer fluid, which is the hot heat exchanger 20 in the main flow direction 46 flows through, loses thermal energy on its way and cools down. As a result, the heat flow is near the exit 44 smaller than near the entrance 42 ,

By the rib structure according to the invention 52 can be achieved here a homogenization.

Through the rib-free areas 78 at the rib structure 52 (which in the height direction 76 parallel to each other) through the formation of second areas 88 and first areas 86 , By the distances D ₁ and D ₂ and by minimizing the length L _T to at most 70 mm can be equalized and thereby achieve an improved efficiency can be achieved.

It has been shown that providing rib-free areas 78 is very effective to obtain a uniformity in the direction x.

Furthermore, the provision of increased heat capacity and increased heat dissipation capability in areas closer to the exit 44 lie as compared to areas closer to the entrance 42 equalization, that is, the formation of second areas 88 and first areas 86 leads to a homogenization.

In 9 a diagram is shown for a temperature of the hot heat exchanger 20 on the flat side 28a respectively 28b if the rib structure 52 Flow channels with a wave structure, as in 8th shown. The corresponding curve is denoted by the reference numeral 120 designated. In comparison, there is a curve 122 shown in which no difference between the first area 86 and the second area 88 that is, in which the heat-absorbing capacity and the heat-releasing ability are constant over the length x.

It can be seen that in the provision of the second area 88 with a wave structure (with rib areas with transverse orientation 92 ) the temperature at the flat side 28a respectively 28b is increased. As a result, there is a higher heat flow and the efficiency is increased.

Through rib areas with transverse orientation 92 , such as by a partial wave structure according to the embodiment as in 8th shown, so a homogenization is achieved.

By the distance D ₁ between the rib structure 52 and the first end 102 the thermoelectric device 17 that is, by resetting the rib structure 52 opposite the thermoelectric device 17 becomes the heat transfer capability to the thermoelectric device 17 in the area of the entrance 42 reduced.

By the distance D ₂ , over which the rib structure 52 via the thermoelectric device 17 stands out in the area of the exit 44 the heat-releasability in this area to the thermoelectric device 17 improved.

As already mentioned, a relatively short length L _{H has} the advantage that a relatively uniform hot side on the hot heat exchanger 20 is reachable.

For a thermoelectric generator device 10 With a high power density, it is also advantageous if the flow channels 70 in the width direction 74 are tight and in the height direction 76 are high. It has been shown that it is advantageous if the width b is at most 0.75 mm and the height H is at least 13 mm.

It can be a large number of ribs 72 position at a close distance. It is then no longer necessary, for example, to make a reduction in a buckling length over an entire length.

The mutual support of the plates 56 in the rib structure 52 ensures especially in areas close to the entrance 42 for a high mechanical stability, so that higher contact pressures can be used.

In the area of the entrance 42 is through the rib-free areas 78 and also by the concern of plates 56 the surface for heat absorption and then heat release relatively low. This can be a homogenization achieve.

Through the production by means of single plates 56 lets go of the ribbed structure 52 realize in a simple way.

LIST OF REFERENCE NUMBERS

10

 Thermoelectric generator device

12

 casing

14

 combination

16

 First cold heat exchanger

17

 Thermoelectric device

18

 First thermoelectric situation

20

 Hot heat exchanger

22

 Second thermoelectric situation

24

 Second cold heat exchanger

26

Housing of the heat exchanger 20

28a

 flat side

28b

 flat side

30

 First wall

32

 Second wall

34

 partition

36

 partition

38

 First shell

40

 Second shell

42

 entrance

44

 output

46

 Main flow direction

48

 flange

50

 flange

52

 rib structure

54

 plate pack

56

 plate

56 '

 plate

56 ''

 plate

58a

 long side

58b

 long side

60

 support area

62

 Area

64

 channel

66

 page

68

 page

70

 flow channel

72

 rib

74

 width direction

76

 height direction

78

 Rib-free area

80

 boundary line

82

 mirror axis

84

 support strut

86

 First area

88

 Second area

90

 longitudinal direction

92

 Rib area with transverse orientation

94

 First end

96

 Second end

98

 The End

100

 crossing

102

 First end

104

 Second end

106

 element

108

 support member

110

 positioner

112

 opening

114a

 retaining element

114b

 retaining element

116

 channels

118

 Thermoelectric module

120

 Curve

122

 Curve

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102013112911 [0002, 0052, 0076]
• DE 102010042603 A1 [0003]
• DE 102007063171 A1 [0004]
• DE 102007063173 A1 [0005]
• DE 102007063196 A1 [0006]
• DE 102009013535 A1 [0007]
• DE 102008005334 A1 [0008]
• DE 102010001417 A1 [0009]
• KR 20120112185 [0010]

Claims (40)

Thermoelectric generator device comprising a thermoelectric device ( 17 ), and a heat transfer device with at least one heat exchanger ( 20 ) and with at least one cold heat exchanger ( 16 ; 24 ), which are in thermal contact with the thermoelectric device ( 17 ), wherein at least the at least one hot-heat exchanger ( 20 ) is provided for the passage of a gas as a heat transfer fluid, and wherein the at least one hot heat exchanger ( 20 ) and / or the at least one cold heat exchanger ( 16 ; 24 ) a rib structure ( 52 ) with flow channels ( 70 ), and flow channels ( 70 ) between ribs ( 72 ) of the rib structure ( 52 ) are formed, characterized in that flow channels ( 70 ) a width (B) in a width direction ( 74 ) of not more than 0.75 mm, the width direction ( 74 ) a spacing direction between spaced ribs (FIG. 72 ). Thermoelectric generator device according to claim 1, characterized in that flow channels ( 70 ) a height (H) in a height direction ( 76 ) of at least 11 mm and preferably at least 13 mm, the height direction ( 76 ) transverse to the width direction ( 74 ) and transversely to a main flow direction ( 46 ) is oriented by heat transfer fluid. Thermoelectric generator device according to claim 1 or 2, characterized in that the thermoelectric device ( 17 ) at least one thermoelectric layer ( 18 ; 22 ) with a first end ( 102 ) and a first end ( 102 ) opposite second end ( 104 ), wherein the first end ( 102 ) an entrance ( 42 ) for heat transfer fluid of the at least one hot heat exchanger ( 20 ) and / or the at least one cold heat exchanger ( 16 ; 24 ), and the second end ( 104 ) an output ( 44 ) for heat transfer fluid of the at least one hot heat exchanger ( 20 ) and / or the at least one cold heat exchanger ( 16 ; 24 ) is facing. Thermoelectric generator device according to claim 3, characterized in that a distance direction between the first end ( 102 ) and the second end ( 104 ) of the at least one thermoelectric layer ( 18 ; 22 ) parallel to a main flow direction ( 46 ) for heat transfer fluid in the at least one hot-heat exchanger ( 20 ) and / or the at least one cold heat exchanger ( 16 ; 24 ). Thermoelectric generator device according to claim 3 or 4, characterized in that a distance (L _T ) between the first end (L 102 ) and the second end ( 104 ) is in the range between 30 mm and 70 mm. Thermoelectric generator device according to one of claims 3 to 5, characterized in that at least in the at least one hot heat exchanger ( 20 ) a first end ( 94 ) of the rib structure ( 52 ), which is the entrance ( 42 ), opposite the first end ( 102 ) of the at least one thermoelectric layer ( 18 ; 22 ) in a main flow direction ( 46 ), wherein in the main flow direction ( 46 ) the first end ( 102 ) of the at least one thermoelectric layer before the first end ( 94 ) of the rib structure ( 52 ) lies. Thermoelectric generator device according to claim 6, characterized in that a distance (D ₁ ) between the first end (D ₁ ) 102 ) of the at least one thermoelectric layer ( 18 ; 24 ) and the first end ( 94 ) of the rib structure ( 52 ) is in the range between 1 mm and 3 mm. Thermoelectric generator device according to one of claims 3 to 7, characterized in that a second end ( 96 ) of the rib structure ( 52 ), which corresponds to the output ( 44 ), opposite the second end ( 104 ) of the at least one thermoelectric layer ( 18 ; 24 ), wherein the second end ( 104 ) of the at least one thermoelectric layer ( 18 ; 24 ) relative to a main flow direction ( 46 ) of heat transfer fluid before the second end ( 96 ) of the rib structure ( 52 ) lies. Thermoelectric generator device according to claim 8, characterized in that a distance (D ₂ ) between the second end ( 104 ) of the at least one thermoelectric layer ( 18 ; 24 ) and the second end ( 96 ) of the rib structure ( 52 ) is in the range between 2 mm and 10 mm. Thermoelectric generator device according to one of claims 3 to 9, characterized in that in a direction transverse to a direction between the first end ( 102 ) and the second end ( 104 ) of the at least one thermoelectric layer ( 18 ; 22 ) the thermoelectric device ( 17 ) is narrower than the rib structure ( 52 ), in particular the rib structure ( 52 ) with a supernatant in the range between 1 mm and 5 mm via the thermoelectric device ( 17 protrudes). Thermoelectric generator device according to the preamble of claim 1 or one of the preceding claims, characterized in that the rib structure ( 52 ) an input for heat transfer fluid facing an area ( 78 ), which is free of ribs. Thermoelectric generator device according to claim 11, characterized in that the rib-free region ( 78 ) mirror-symmetrical to an axis ( 82 ) is trained. Thermoelectric generator device according to claim 11 or 12, characterized in that the rib-free region ( 78 ) has a length which is between 20% and 50% of a total length (L _H ) of the rib structure ( 52 ) between a first end ( 94 ) and a second end ( 96 ) of the rib structure ( 52 ), and in particular between 30% and 50% and preferably between 30% and 45% of the total length (L _H ). Thermoelectric generator device according to one of claims 11 to 13, characterized in that the rib-free region ( 78 ) has a width which extends from a first end ( 94 ) of the rib structure ( 52 ) to a second end ( 96 ) of the rib structure ( 52 ) decreases. Thermoelectric generator device according to claim 14, characterized in that the width decreases monotonically. Thermoelectric generator device according to one of claims 11 to 15, characterized in that the rib-free region ( 78 ) a curved boundary line ( 80 ) having. Thermoelectric generator device according to one of claims 11 to 16, characterized in that the rib-free region ( 78 ) a boundary line ( 80 ) according to a logarithmic function. Thermoelectric generator device according to one of claims 11 to 17, characterized in that in the rib-free region ( 78 ) at least one support strut ( 84 ) is arranged on the rib structure. Thermoelectric generator device according to claim 18, characterized in that at least one support strut ( 84 ) transversely to a longitudinal direction ( 90 ) of flow channels ( 70 ) is oriented. Thermoelectric generator device according to the preamble of claim 1 or one of the preceding claims, characterized in that the rib structure ( 52 ) a first area ( 86 ), in which flow channels ( 70 ) parallel to a main flow direction ( 46 ) and a second area ( 88 ) which adjoins the first area ( 86 ) and in which the rib structure ( 52 ) compared to the first area ( 86 ) has an increased heat absorption capacity from the heat transfer fluid. Thermoelectric generator device according to claim 20, characterized in that flow channels ( 70 ) in the second area ( 88 ) are arranged parallel to each other. Thermoelectric generator device according to claim 21, characterized in that the increased heat absorption capacity in the second region ( 88 ) by guiding flow channels ( 70 ) and / or by material selection of ribs ( 72 ) is made. Thermoelectric generator device according to one of claims 20 to 22, characterized in that the rib structure ( 52 ) in the second area ( 88 ) Rib areas ( 92 ) with a transverse orientation to the main flow direction ( 46 ) having. Thermoelectric generator device according to one of claims 20 to 23, characterized in that ribs ( 72 ) in the second area ( 88 ) have a wave structure. Thermoelectric generator device according to one of claims 20 to 24, characterized in that the rib structure ( 52 ) in the second area ( 88 ) is made of a material which, compared to a material of the rib structure ( 52 ) in the first area ( 86 ) has a higher thermal conductivity. Thermoelectric generator device according to one of claims 20 to 25, characterized in that the second region ( 88 ) at least 30% of a total length (L _H ) of the rib structure ( 52 ) between a first end ( 94 ) and a second end ( 96 ) of the rib structure ( 52 ) begins. Thermoelectric generator device according to one of Claims 20 to 26, characterized in that the first region ( 86 ) at least partially at a rib-free area ( 78 ) of the rib structure ( 52 ) lies. Thermoelectric generator device according to one of the preceding claims, characterized in that the rib structure ( 52 ) is made of a metallic material. Thermoelectric generator device according to claim 28, characterized in that that the rib structure ( 52 ) is made of nickel and in particular pure nickel. Thermoelectric generator device according to claim 28 or 29, characterized in that the ribbed structure ( 52 ) is made of stainless steel. Thermoelectric generator device according to the preamble of claim 1 or one of the preceding claims, characterized in that the rib structure ( 52 ) a plurality of plates ( 56 ) on which channels ( 64 ) are formed, that the plates ( 56 ) are oriented parallel to each other, that adjacent plates ( 56 ' . 56 '' ) abut each other and that flow channels ( 70 ) over the channels ( 64 ) in a plate ( 56 ) and plate portions of an adjacent plate are formed. Thermoelectric generator device according to claim 31, characterized in that the plates ( 56 ) are separate individual plates. Thermoelectric generator device according to claim 31 or 32, characterized in that the plates ( 56 ) are designed as Gleichplatten. Thermoelectric generator device according to one of claims 31 to 33, characterized in that a plate ( 56 ) at least one positioning element ( 110 ) and / or at least one support element ( 108 ) for one or more further plates ( 56 '; 56 '' ). Thermoelectric generator device according to claim 34, characterized in that as a positioning element ( 110 ) at least one opening ( 112 ) is provided. Thermoelectric generator device according to one of Claims 31 to 35, characterized by a plate pack ( 54 ), in which a plurality of plates ( 56 ) are connected to a package and in particular clamped together. Thermoelectric generator device according to claim 36, characterized by at least one retaining element ( 114a . 114b ), which on the disk pack ( 54 ) is arranged, and in particular by at least two opposing holding elements ( 114a . 114b ), where the disk pack ( 54 ) via the at least one retaining element ( 114a ; 114b ) on a housing ( 26 ) is held. Thermoelectric generator device according to claim 37, characterized in that the housing ( 26 ) a first shell ( 38 ) and a second shell ( 40 ), between which the at least one hot-heat exchanger ( 20 ) is arranged. Thermoelectric generator device according to one of the preceding claims, comprising a housing ( 12 ) and at least one combination ( 14 ) with the components of the first cold heat exchanger ( 16 ), second cold heat exchanger ( 24 ), first thermoelectric layer ( 18 ), second thermoelectric layer ( 22 ) and heat exchangers ( 20 ), wherein in the at least one combination ( 14 ) of the heat exchangers ( 20 ) between the first thermoelectric layer ( 18 ) and the second thermoelectric layer ( 22 ), the first cold heat exchanger ( 16 ) at the first thermoelectric layer ( 18 ) and the second cold heat exchanger ( 24 ) at the second thermoelectric layer ( 22 ), and wherein the at least one combination ( 14 ) in the housing ( 12 ) is positioned. Thermoelectric generator device according to claim 39, characterized in that a first inner side of a first wall of the housing ( 12 ) in direct planar mechanical contact with the first cold heat exchanger ( 16 ) of the at least one combination ( 14 ) or the first wall is a wall of the first cold heat exchanger ( 16 ) forms that a first inner side opposite second inner side of a second wall of the housing ( 12 ) in direct planar mechanical contact with the second cold heat exchanger ( 24 ) of the at least one combination ( 14 ) or another combination or a wall of the second cold heat exchanger ( 24 ) and that the housing ( 12 ) provides a contact pressure by positive locking at least at one operating point or operating point range of the thermoelectric generator device, which pressure produces the components of the at least one combination ( 14 ) braced against each other and in the housing ( 12 ).

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