EP3314176A1

EP3314176A1 - Temperature-control unit for a gaseous or liquid medium

Info

Publication number: EP3314176A1
Application number: EP16735834.0A
Authority: EP
Inventors: Vedran BURAZER; Michael Buchner
Original assignee: AVL List GmbH
Current assignee: AVL List GmbH
Priority date: 2015-06-23
Filing date: 2016-06-21
Publication date: 2018-05-02
Also published as: WO2016207153A1; KR20180020240A; JP2018520331A; AT516611A4; US20180164003A1; AT516611B1; CN107995946A

Abstract

The invention relates to a temperature-control unit for a gaseous or liquid medium having a high-dynamic temperature control of the medium. According to the invention, the temperature-control unit (1) comprises a base body (2), a cooling body (5), between which a number of thermoelectric modules (7) is arranged, and a medium line (6) in the base body (2), wherein the medium line (6) in the base body (2) is arranged in the form of a single-start spiral, which is guided from the outside to the inside. It is provided that the number of thermoelectric modules (7) are arranged in a plurality of rows on the base body (2), wherein the modular heating power of a thermoelectric module (7) which is located radially further towards the outside is greater than the modular heating power of a thermoelectric module (7) which is located radially further towards the inside.

Description

Temperature control unit for a gaseous or liquid medium

The subject invention relates to a temperature control unit for tempering a gaseous or liquid medium by means of a number of thermoelectric modules, which are arranged between a base body and a heat sink, and in the base body a media line is arranged through which flows through the gaseous or liquid medium, wherein the media line is arranged guided in the base body in the form of a catchy spiral from outside to inside.

For the exact measurement of the fuel consumption of an internal combustion engine on a test bench, a precise conditioning of the temperature and the pressure of the fuel supplied to the internal combustion engine is necessary. The measurement of fuel consumption is often done with a known Coriolis flow sensor. An example of such measurement of fuel consumption can be found in US 2014/0123742 A1, which focuses on the conditioning of liquid fuels. Therein, the temperature of the fuel is controlled via a heat exchanger with a cooling liquid. Strong load changes cause strong fluctuations in fuel consumption and in the return temperature of the fluid (inlet temperature). However, such a heat exchanger is sluggish and allows only slow temperature changes. Thus, the conditioning described by means of heat exchanger for heavy load changes (input temperature changes) is unsuitable. This leads to the current state of the art that after such a load change a calming time must be maintained. During this time, the temperature is unstable and high-precision measurement is not possible for flow sensors. For a more independent of the input temperature changes operation, either the power density of the heat exchanger would have to be increased. However, this is not technically feasible and requires, if at all possible, a redesign of the heat exchanger. At constant power density would in turn result in a much larger footprint. Another possibility might be a more aggressive control behavior of the heat exchanger. However, this in turn means greater overshoot and undershoot and concomitantly poorer dynamics with regard to possible setpoint temperature changes. However, enlarging the heat exchanger would only help with liquids. For gaseous media, a change in flow will directly cause a pressure change and a setpoint temperature change. Thus, the heat exchanger would have to allow extremely fast setpoint temperature changes, but this is not practical feasible for a heat exchanger operated with cooling liquid. For this, the available power would have to be increased even more with constant mass, only to increase the power would have no benefit in this case. Alternatively, the controller of the heat exchanger remains even more aggressive to adjust, but in turn, even greater Over- and undershoot would entail. An accurate and fast temperature control would not be possible.

The dynamic temperature control by means of a heat exchanger, so if no constant temperature is set, is also still relatively inaccurate. Apart from that, such a heat exchanger requires additional components and controls for operating the heat exchanger, which also makes the system more expensive.

In DE 10 2010 046 946 A1 it is proposed to temper the temperature of the fuel in a conditioning plant by means of thermoelectric modules (so-called Peltier elements). This is due to the low storage masses achieved a highly dynamic temperature control possible with which the fuel can be both heated and cooled. This device is also aimed specifically at the conditioning of liquid fuels.

For gaseous fuels, such as natural gas or hydrogen, there is the added problem that the gaseous fuel is typically under high pressure and, consequently, for use as fuel in an internal combustion engine, it must first be depressurized to a required, lower pressure , When relaxing the gaseous fuel, such as natural gas, but the fuel cools down sharply, which can be problematic for subsequent components of the conditioning, for example, by condensation and icing of the gas lines or other components in the gas line. Therefore, the gaseous fuel is usually heated prior to relaxing, so that the relaxation results in a desired temperature of the fuel. Due to fluctuations in the pressure of the supplied gaseous fuel and also due to the dependence of the temperature after the relaxation of the composition of the gaseous fuel, which may also vary, the temperature control of the gaseous fuel before relaxing must be highly dynamic to the temperature after the relaxation and to be able to keep constant before the flow measurement. In addition, the required heating power for controlling the temperature of the fuel is also heavily dependent on the current flow, which also makes a highly dynamic temperature control required with rapidly changing flow rates.

On the one hand, such a highly dynamic temperature control requires a control method which is capable of carrying out highly dynamic (in terms of rapid temperature changes) control interventions and, on the other hand, a temperature control unit which is also able to implement the highly dynamic control interventions. Consequently, such a temperature control unit must be able to impress the required temperature changes on the fuel flowing through in a very short time. In addition, high temperature stability is also desirable, even if under certain circumstances no high demands are placed on the dynamics of the temperature. be made because of certain applications, a highly accurate and highly stable temperature control is required. These requirements require a temperature control unit with a high heating and cooling capacity, which may also be necessary to change quickly between heating and cooling. Apart from that, a precise temperature control must be possible in order to avoid excessive overheating (either overheating or overcooling).

DE 10 2010 046 946 A1 indicates that low thermal storage masses of the temperature control unit are advantageous for highly dynamic temperature control.

US 6,502,405 B1 shows a heat exchanger element with Peltier elements for heating or cooling fuel in a vehicle. The heat exchanger element consists of a heat conducting block in which a fuel line is inserted meandering and which is thermally insulated on a first side. Peltier elements, which are thermally connected to a heat sink, are arranged on the second side of the heat-conducting block. The heat sink is typically designed with a large surface area and small mass of memory to maximize heat dissipation capacity. In addition, a fan is still arranged on the heat sink in order to increase the heat dissipation capacity even further. Thus, the heat exchanger element of US Pat. No. 6,502,405 B1 is also designed for a low thermal storage mass in order to be able to dissipate heat quickly to the environment via the heat sink. Due to the meandering guidance of the fuel in the heat exchanger element but it also leads to an uneven heating of the fuel, which makes the temperature control difficult, since the Peltier elements are all driven with the same supply voltage. The uneven heating results in a higher temperature difference between the outlet temperature of the medium and the surface of the Peltier elements, which in turn leads to a lower maximum outlet temperature of the medium, since the Peltier elements can not be heated arbitrarily. Or it results in a lower maximum flow rate for a given outlet target temperature. Apart from that, more thermal energy is stored in the Wärmeleitblock by the higher temperature difference, which must be reduced again in the case of a desired temperature change, which makes the heat exchanger element but in turn slower. For a more uniform heating of the fuel, the individual Peltier elements would have to be matched to one another, i. different Peltierlemente along the fuel line, or the Peltier elements would have to be individually supplied and regulated. Both would be very expensive and therefore disadvantageous.

However, the above-mentioned problems can basically occur with any gaseous or liquid medium which is to be tempered in a temperature control unit, and not only with fuel. From EP 003 822 A1 a temperature control unit for the temperature control of a liquid flow is shown which has a main heat exchanger, a heat exchanger and interposed Peltier elements. A media line for controlling the temperature of a liquid flow is arranged in the main heat exchanger and is guided spirally from outside to inside. In this case, a pre-tempering takes place in the heat-auxiliary exchanger and the Peltier elements are used for precise and rapid adjustment of a desired temperature.

Based on this prior art, it is an object of the subject invention to provide a temperature control unit for a gaseous or liquid medium, which allows a particularly highly dynamic and accurate temperature control of the medium. This object is achieved by a tempering unit mentioned in the introduction according to the invention that the number of thermoelectric modules are arranged in several rows on the base body, wherein the Modulheizleistung a radially further outer thermoelectric module is greater than the Modulheizleistung a radially further inside thermoelectric module. This achieves a very efficient temperature control. The inflowing medium from the outside can be tempered in the radially outer region with high heat output, which enables strong and rapid temperature changes. Within the scope of the present disclosure, a module heat output of a thermoelectric module is understood to be both the rated output at a nominal voltage and a nominal current, as well as the output at a specific supply voltage that deviates from the rated voltage or a specific one that deviates from the rated current Supply current sets. The modules are preferably coordinated so that the temperature spread at maximum flow between module surface and medium outlet temperature is minimal. As has been shown, this is the case when all modules have almost the same surface temperature. Due to the circumferential arrangement, the thermoelectric modules within a row of the house are almost at the same temperature. Only the different rows would have to be adjusted in this respect, which, in contrast to a meandering arrangement of the media line, represents a substantial simplification since it is no longer necessary to adjust all thermoelectric modules for the same result (minimum temperature spread).

In addition, the module heating power can be optimally adapted to the conditions and it can be installed radially inside modules with smaller module heating.

If the heating power in the radially outer region of the basic body, as the sum of the module heating powers of the thermoelectric modules in the radially outer region, is greater than the heating power in the radially inner region of the basic body, as the sum of the modulus heating capacities. conditions of the thermoelectric modules in the radially inner region, the temperature of the medium can also be optimized by the arrangement and selection of the Modulheizleistung the individual thermoelectric modules and it can be a very uniform heating of the medium can be achieved. In other words, according to the invention, the number of thermoelectric modules is arranged in a plurality of rows on the main body and the module heating power of a radially outer thermoelectric module is set greater than the Modulheizleistung a radially further inside thermoelectric module. The adjustability of the module heating power can be achieved both by the choice of modules with different nominal powers and by different supply voltage or current values.

The arrangement of the media line in the main body in the form of a catchy spiral, a particularly uniform and efficient temperature control of the medium can be achieved. Due to the spiral shape, the temperature control can be made very compact, since the spiral paths can be arranged close together. As a result, a thermoelectric module can also cover several spiral paths, which improves the efficiency of the temperature control unit and the uniformity of the heating. This allows a particularly highly dynamic, accurate and stable temperature control of the medium can be achieved.

It is particularly advantageous if the mass ratio of the thermal storage mass of the heat sink to the thermal storage mass of base body and disposed therein media line in the range of 0.5 to 1, advantageously in the range of 0.7 to 0.8, and very particularly advantageous with 0 , 75 is chosen. It has been found that for a highly dynamic temperature control of a medium by means of a tempering unit according to the preamble of claim 1, especially when a rapid and frequent change in the direction of the heat flow is required, too low a storage mass, as suggested by the prior art, disadvantageous is. Surprisingly, it has been found that a certain mass ratio between the mass of the heat sink and the mass of the main body together with the media line arranged therein is advantageous for the temperature control. The reason for this is evidently that a thermal storage mass is formed by the larger mass of the heat sink and thus not too fast thermal energy is released to the environment. This stored energy can then be used to assist in heating the fuel as needed, thereby allowing the temperature to be controlled more quickly and accurately.

A compact embodiment of the temperature control unit is obtained if a groove is provided in the main body into which the media line is pressed. In order to concentrate the thermal energy in the base body and to prevent excessive outflow of thermal energy, the base body is advantageously surrounded by a base body shell, wherein over the circumference of the base body a plurality of radial connecting webs are arranged, which are connected to the base body shell. This also increases the efficiency of the temperature control unit. This can be further improved if the body shell is made partially hollow, since thus an even better thermal insulation between the body and the environment is achieved.

It can be advantageous to arrange a cooling line in the heat sink, through which, as required, cooling medium flows to cool the heat sink in order to be able to dissipate heat more quickly from the heat sink. This can be particularly useful for gases without pronounced Joule-Thomson effect or in liquid media, since in these cases, a frequent reversal of the thermoelectric modules may be necessary. The cooling line is advantageously arranged spirally again.

The subject invention will be explained in more detail below with reference to Figures 1 to 7, which show by way of example, schematically and not by way of limitation advantageous embodiments of the invention. It shows

1 shows a perspective view of the temperature control unit according to the invention,

2 shows a view of the temperature control unit with the heat sink removed,

3 and 4 views of the main body of the temperature control,

5 shows a view of the media line in the temperature control,

6 shows a further advantageous arrangement of the media line in the main body and Figure 7 shows a temperature control unit with a cooling line in the heat sink.

1 shows a perspective view of the temperature control unit 1 according to the invention. The tempering unit 1 consists of a base body 2, to which any fastening elements 3, such as, for example, feet in the exemplary embodiment shown, can be provided for fastening the tempering unit 1. On the first side of the main body 2, a thermal insulation element 4 is arranged and on the opposite second side, a heat sink 5. By the temperature control unit 1, a media line 6 is performed, through which a gaseous or liquid medium, such as fuel, flows in the Temperper 1 is tempered to a desired temperature. The media line 6 has for this purpose an input terminal 10 and an output terminal 1 1, whereby the flow direction of the medium is determined by the temperature control unit 1 (indicated in Figure 1 by the arrows). FIG. 2 shows the temperature control unit 1 with the heat sink 5 removed. This shows a number of thermoelectric modules (Peltier elements) 7, which are arranged on the base body 2. As is known, a thermoelectric module 7 is a semiconductor element which is arranged between a first heating surface 9a (not visible in FIG. 2) facing the main body 2 and a second heating surface 9b (here facing the heat sink). Depending on the polarity of the electrical voltage supplied to the semiconductor element, either the first heating surface 9a is warmer than the second heating surface 9b, or vice versa. After the structure and function of such thermoelectric modules 7 are well known and such thermoelectric modules 7 are commercially available in different performance classes, will not be discussed in more detail here.

Thus, with such a thermoelectric module 7 depending on the polarity of the supply voltage, which is supplied for example via the terminals 8, both heated and cooled. "Heating" here means that the base body 2 heat is supplied and "cooling" that the main body 2 heat is removed. Thus, with the thermoelectric modules 7, the heat flow between the base body 2 and the heat sink 5 can be influenced.

The thermoelectric modules 7 are via a first heating surface 9a (not visible in Figure 2) directly or indirectly (for example via a heat transfer element to improve the heat conduction) in thermal contact with the main body 2. The heat sink 5 is on the second heating surface 9b of the thermoelectric module and is in thermally conductive contact, again directly or indirectly, with this second heating surface 9b. The heat sink 5 and the main body 2 are not arranged adjacent to each other in order to avoid a direct thermally conductive contact between the heat sink 5 and the main body 2 (as shown in Figure 1). The basic body 2 is shown in detail in FIGS. 3 and 4, which show different views of the main body 2. 3 shows the side of the main body 2, on which the thermoelectric modules 7 are arranged. The main body 2 is essentially formed from a base plate 20, which is surrounded along its circumference by a main body shell 21. The main body shell 21 is connected via radial connecting webs 22 with the base plate 20, wherein the connecting webs 22 are arranged distributed over the circumference of the base plate 20. In the circumferential direction between the connecting webs 22 thereby cavities 23 are formed, which act as thermal insulation between the base plate 2 and the main body shell 21. By the connecting webs 22 and the cavities 23, the heat flow from the base plate 20 in the main body shell 21 is considerably lessened. As a result, the heat introduced by the thermoelectric modules 7 into the base plate 20 remains concentrated therein and flows only to a slight extent over the latter Body shell 21 to the environment. This also ensures that the base body shell 21, and thus also the temperature control unit 1, does not overheat on the outside, and that parasitic heat flows which reduce the performance and dynamics of the conditioning are kept as small as possible. The main body shell 21 may additionally be made partially hollow by 21 circumferential slots 24 are incorporated in the main body shell, which also form cavities for additional thermal insulation.

4, the other side of the base body 2 is shown. Here it can be seen that at the back of the base plate 20, a preferably spiral groove 25 is formed, in the assembled state, the media line 6 is pressed. The groove 25 forms in the base body 2 a catchy planar spiral (Archimedean spiral, logarithmic spiral). The media line 6 is preferably guided spirally inwards from the outside and emerges from the temperature control unit 1 in the central inner region of the base plate 20, the media line 6 being deflected out of the plane of the spiral when exiting, preferably by about 90 ° the media line 6 easy to be able to lead out of the temperature control unit 1. In principle, however, any other guidance of the media line 6 in the main body 20 is conceivable.

The use of a media line 6 in the form of a catchy spiral is very expensive to produce since the media line 6 extends in all three dimensions in this case.

In an alternative embodiment, the media line 6 is arranged on the base body 2 in the form of a two-flighted planar spiral (also called Fermat's spiral), as will be described with reference to FIG. For this purpose, in turn, a correspondingly shaped groove 25 for receiving the media line 6 may be formed in the main body 2. Via a first spiral passage 27, the medium in the media line 6 is guided spirally radially from the outside to the center inside. Centrally inside, the first spiral passage 27 is connected to a second spiral passage 28, via which the medium in the media conduit 6 is guided spirally from radially inward to radially outward. Due to the double-threaded design of the groove 25 are always radially a first spiral passage 27 and a second spiral passage 28 adjacent to each other. The medium is thus supplied radially on the outside via the input terminal 10 and discharged radially outside via the output terminal 1 1. The double-flighted spiral has the advantage that the media line 6 does not have to be deflected out of the plane of the spiral, which is easier to manufacture. For the double-flighted spiral has the disadvantage that the inflowing medium cools the outflowing medium, which requires a little more power and a less uniform heating is feasible. The temperature spread gets bigger, but the thermoelectric modules of a series, in the case of tuned modules, are still at approximately the same temperature.

Of course, the catchy or double-flighted spiral need not necessarily be designed as a circular spiral, but may also have other shapes, such as rectangular, square, etc., have. Due to the spiral shape, the temperature control unit 1 can be made very compact, since the spiral passages can be arranged close to each other. This can be accommodated in a small space a lot of meters on the media line 6, which increases the available surface for temperature control of the medium flowing through the media line 6 medium.

In order to be able to realize a tight packing of the media line 6, 6 prescribed minimum bending radii must not be fallen short of in the shaping of the media line. A meandering guide the media line would be disadvantageous in this regard, since the required bending radii for a dense packing are considerably smaller than in a spiral course. With increasing pressure requirements on the part of the media line 6 increases due to the required wall thickness increase usually also the minimum bending radius. A meander-shaped guide therefore has a particularly disadvantageous effect on high pressure requirements, as in the present case.

5 shows still the thermal insulation element 4 with the advantageous catchy spiral-shaped media line 6, which is pressed into the base body 20 in the assembled state. The thermal insulation element 4 ensures that the heat introduced by the thermoelectric modules 7 into the base plate 20 remains concentrated therein and is not released via the end face of the temperature control unit 1 to the environment.

The thermoelectric modules 7 are preferably circular, or adapted to the spiral shape, and arranged in several rows (ie at different radial distances) on the base plate 20 (Figure 2). As a result, more thermoelectric modules 7 can be arranged radially on the outside due to the resulting larger circumference. The inflowing medium is thus tempered in the radially outer region with high heating power (sum of the module heat outputs of the radially outer modules 7 involved), which enables strong and rapid changes in temperature. It is further advantageous if a thermoelectric module 7, which is arranged radially further inwards, has a lower module heating power than a thermoelectric module 7, which is arranged radially further outward. After the media line 6 is preferably guided in a spiraling manner inwards, fewer and weaker (in the sense of less module heating power) thermoelectric modules 7 extend radially inwards for temperature control of the medium. The radially inward necessary heating power (sum of the module heat outputs of the participating radially inner modules 7) is thus lower than the heating power in the radially outer region. This allows the temperature of the medium can also be optimized by the arrangement and selection of the module heating power of the individual thermoelectric modules 7 and it can be a very uniform heating of the medium can be achieved.

The module heat output of a thermoelectric module 7 is generally understood to mean the rated output at a rated current / nominal voltage, as well as the power which occurs at a specific current / voltage deviating from the rated current / nominal voltage. Accordingly, according to the invention, on the one hand, thermoelectric modules 7 with different power ratings, differently adjustable thermoelectric modules 7 with different or the same power ratings or combinations thereof can be used.

If an electrical supply voltage is applied to a thermoelectric module 7, as is known, one of the heating surfaces 9a, 9b of the thermoelectric module 7 is cooled, while at the same time the opposing heating surface 9a, 9b is heated. The maximum temperature spread between the heating surfaces 9 a, 9 b depends on the operating temperature (temperature at the warmer heating surface) of the thermoelectric module 7. The higher the operating temperature, the higher the maximum achievable temperature spread between cold and hot heating surface 9a, 9b. Thus, with available thermoelectric modules 7 temperatures of up to 200 ° C can be achieved on the hot heating surface, the cold heating surface does not exceed 100 ° C. By simply reversing the supply voltage, a highly dynamic control of the temperature is made possible. This control is supported in the temperature control unit 1 according to the invention by the heat sink 5 in the heating mode, so when the medium is to be heated in the media line 6, is used as a buffer memory. For this purpose, however, the thermal storage mass is not as small as possible, as suggested in the prior art, but a certain storage mass is desired in order to be able to realize this.

It has been found to be advantageous if the mass ratio of the thermal storage mass of the heat sink 5 to the thermal storage mass of the base body 2 and disposed therein media line 6 in the range of 0.5 to 1, advantageously 0.7 to 0.8, is selected. A particularly advantageous temperature controllability of the temperature control unit 1 was found at a mass ratio in the range of 0.75, or at a mass ratio of 0.75. For example, a tempering unit 1 that was tested had a thermal storage mass of the heat sink 5 of 5.4 kg and a thermal storage mass of the base body 2 and the media line 6 arranged therein of 7.2 kg, which resulted in a mass ratio of 0.75. In an embodiment as in Figure 3 or Figure 6, in which the base body shell 21 is thermally separated from the base body 2 via cavities 23, the mass of the base body shell 21 is not calculated to the thermal storage mass of the body. Likewise, the insulation element 4 is not part of the thermal storage mass of the main body 2. With constant heating demand of the temperature control unit 1, ie at a constant voltage supply of the thermoelectric modules 7, a stable temperature spread arises at the thermoelectric modules 7. As soon as less thermal energy or heat is required for tempering the medium, the supply voltage is reduced at the thermoelectric modules 7, whereby the temperature spread is lower. Thus, the temperature at the voltage applied to the base plate 20 heating surface 9a of the thermoelectric module 7. At the same time, the temperature rises at the opposite heating surface 9b. This results in a temperature gradient between the heating surface 9b and the heat sink 5 resting against it, as a result of which heat flows into the heat sink 5 and, due to the thermal storage mass of the heat sink 5, is not immediately dissipated to the environment but (at least for a limited time). is cached. This cached thermal energy is the temperature control or the temperature control unit 1 as a support available when more thermal energy is required to control the temperature of the medium again. In this case, the supply voltage would be raised again, whereby the temperature spread at the thermoelectric modules 7 increases again. Thus, the temperature at the heating surface 9b, against which the heat sink 5 abuts, decreases with respect to the temperature of the heat sink 5. This creates a reverse temperature gradient, which leads to the thermal energy stored in the heat sink 5 (heat) flowing into the main body 2 and thus supporting the thermoelectric modules 7. Due to the thermal storage mass of the heat sink 5 can thus be reacted very quickly and accurately with the temperature control unit 1 to load changes or temperature changes and a typical overheating can be largely avoided. For this purpose, the thermal storage mass of the heat sink 5 with respect to the thermal storage mass of the base body 2 and disposed therein media line 6 but not too large or too small. The total surface of the heat sink 5 should be designed as a function of the expected operating temperature so that the heat stored in the heat sink 5 is not released too quickly to the surface, but remains sufficiently long stored in the heat sink 5. The surface is thus not as large as possible and optimized to dissipate the heat as in conventional heat sinks, but on the contrary so that the heat is stored in the heat sink 5. A complete thermal insulation of the heat sink 5 from the environment would also be disadvantageous because in the case of frequent reversals, the temperature could heat up in the heat sink 5.

For different media, if appropriate, the material of the media line 6 and the heating power of the thermoelectric modules 7 or the module heating powers of the thermoelectric modules 7 are to be adapted. The general basic principle with the heat sink 5 as a storage mass to support the temperature control unit 1 remains untouched.

For certain gaseous media, such as natural gas, it comes due to the Joule Thomson effect to a strong cooling by the necessary pressure release. In these gases, the tempering unit 1 generally only needs to preheat the gaseous medium. Cooling of these gases by the temperature control unit 1 is usually not required. Thus, it is usually sufficient for these applications to work only with the temperature spread of the thermoelectric modules 7. A reversal to change from heating to cooling is rather unnecessary. Other gaseous media such as hydrogen, do not show this pronounced effect of strong cooling by the necessary pressure release. On the contrary, it may also come to a warming by the pressure release. When tempering liquid media often no pressure release is necessary because the liquid medium is already present with the right pressure. For gases without pronounced Joules Thomson effect or liquid media, the temperature control unit 1 must therefore often switch between heating and cooling the gaseous medium in order to keep the temperature constant depending on the pressure and the flow. In particular, during cooling, it may be that due to the lower surface of the heat sink 5, the resulting heat, especially the waste heat of the thermoelectric modules 7, can not be dissipated quickly enough. Therefore, when using the temperature control unit 1 with such gaseous or liquid media, it may also be provided to additionally cool the heat sink 5 as required. For this purpose, a cooling line 12 may be introduced into the heat sink 5, is passed through the cooling liquid for additional cooling of the heat sink 5. Such an embodiment is indicated in Fig.7. The cooling line 12 can again be arranged in the heat sink 5 in the form of a catchy or double-flighted spiral, as described above with respect to the media line 6. For this purpose, the heat sink 5 can also be designed in several parts in order to be able to introduce the cooling line 12. Of course, other embodiments of the cooling line 12 are conceivable. In the exemplary embodiment according to FIG. 7, grooves 31 are incorporated in a heat sink main body 30, for example milled in to form the cooling line 12. The grooves 31 are vorzugswiese as described spirally incorporated. The heat sink main body 30 with the grooves 31 is covered with a heat sink cover 32 to form the heat sink 5.

If a separate line is used as cooling line 12 in the heat sink 5 (similar to the media line 6 in the main body), then the cooling line 12 would also be part of the thermal storage mass of the heat sink fifth

In order to connect to the cooling line 12 in the heat sink 5, a Kühlmediumzuführanschluss 34 and a Kühlmediumabführanschluss 33 may be provided on the heat sink. Preferably, the cooling medium is supplied from the inside and discharged centrally outside.

Claims

claims

1 . Temperature control unit for tempering a gaseous or liquid medium by means of a number of thermoelectric modules (7) which are arranged between a base body (2) and a heat sink (5), and in the base body (2) a media line (6) is arranged, through which flows through the gaseous or liquid medium, wherein the media line (6) in the base body (2) is guided guided in the form of a catchy spiral from outside to inside, characterized in that the number of thermoelectric modules (7) in several rows on the base body (2 ), wherein the module heating power of a radially further outward thermoelectric module (7) is greater than the module heating power of a radially further inside thermoelectric module (7).

2. Tempering unit according to claim 1, characterized in that the media line (6) is deflected from the inside of the plane of the spiral and led out of the base body (2).

3. tempering unit according to claim 1 or 2, characterized in that the mass ratio of the thermal storage mass of the heat sink (5) to the thermal storage mass of the base body (2) and disposed therein media line (6) in the range of 0.5 to 1, advantageously in the range from 0.7 to 0.8.

4. tempering unit according to claim 3, characterized in that the mass ratio is 0.75.

5. tempering unit according to claim 1, characterized in that in the base body (2) has a groove (25) is provided in which the media line (6) is pressed.

6. tempering unit according to claim 1, characterized in that the base body (2) by a base body shell (21) is surrounded, wherein over the circumference of the base body (2) a plurality of radial connecting webs (22) are arranged, which with the body shell ( 21) are connected.

7. tempering unit according to claim 6, characterized in that the base body shell (21) is partially hollow.

8. tempering unit according to claim 1, characterized in that in the cooling body (5) a cooling line (12) is arranged, through which, if necessary, cooling medium for cooling the cooling body (5) flows.

9. tempering unit according to claim 8, characterized in that the cooling line (12) is arranged spirally.

10. tempering unit according to one of claims 1 to 9, characterized in that the heating power in the radially outer region of the base body (2), as a sum of Modulheiz- services of the thermoelectric modules (7) in the radially outer region, is greater than the heating power in radially inner region of the base body (2), as the sum of the module heat outputs of the thermoelectric modules (7) in the radially inner region.