EP1864068B1 - Heat exchanger with ventilation - Google Patents

Abstract

The invention relates to a heat exchanger, in particular for a stationary UT heating body ( 1 ) of a motor vehicle heater. According to the invention, said heat exchanger comprises a ventilation device which is embodied as a ventilation bore ( 22, 36 ) which is, in particular, embodied in the separating wall of the upper coolant tank ( 4 ) of the heating body and is located at a distance from the feed and return section ( 10 ).

Description

The invention relates to a heat exchanger for at least one heat transport medium, as used for example as a radiator for heating in the vehicle interior of a motor vehicle incoming air. The invention further relates to a coolant circuit and an air treatment device for motor vehicles using such a heat exchanger.

Heat exchangers are used, inter alia, in motor vehicles for different tasks. For example, heat exchangers for engine cooling in a broader sense z. B. used as a coolant radiator, oil cooler, exhaust gas cooler and intercooler. Another common application of heat exchangers in motor vehicles is the temperature of the air supplied into the passenger compartment. Here are heat exchangers z. B. in the form of evaporators, condensers (or gas coolers), internal heat exchangers and radiators used.

Such heat exchangers now exist in a wide variety of designs and types of installation. If at least one at least partially liquid heat transport medium is used in heat exchangers, as it is z. As is the case with coolant radiators or radiators, if necessary, the problem of air accumulation in the heat exchanger, which may possibly adversely affect the throughput or the uniform distribution of the heat transfer medium in the heat exchanger. This is especially true for standing installed heat exchangers.

In order to ensure a high and as even as possible throughput of the heat transport medium, it may therefore prove necessary to dissipate possibly accumulating in the heat exchanger air. To date, different approaches have been used.

One possibility is to set up the heat exchanger, for example by means of a flat installation position or a corresponding arrangement of flow or return openings, in such a way that air accumulating in the heat exchanger can escape from the heat exchanger or can be removed, for example. when the system is not even accumulated. A problem with such established heat exchangers is that certain installation methods (such as, for example, vertical installation of the heat exchanger) or specific designs of the supply openings for the heat transport medium are in fact excluded. However, this is often problematic especially in motor vehicles, since the space in the front part of the motor vehicle is usually very tight and certain configurations of the heat exchanger due to the other engine compartment modules are partially unavoidable.

Another possible solution is to allow a certain amount of air accumulation in the heat exchanger and to rely on the fact that at a certain throughput of heat transfer medium, the gas collections are entrained in the heat exchanger from the heat transfer medium through the heat exchanger. The problem here is that in particular at low throughputs of heat transport medium the Efficiency of the heat exchanger can be reduced by the accumulation of air from both the absolute performance as well as the uniformity of heat dissipation. In particular, the latter can lead to thermal stresses and be disadvantageous due to the uneven heat distribution on the radiator surface, especially in the treatment of air for the passenger compartment. Another problem is that the radiators tend to cause noise due to the accumulation of gas, which is disadvantageous in particular with components arranged in the vehicle interior (such as, for example, in the case of the radiator of an air conditioning system).

Finally, it has already been proposed in isolated cases to provide small ventilation openings adjacent to the return, so that gas accumulating in the heat exchanger can pass through these ventilation openings and thus leave the heat exchanger. However, such vents can often vent the heat exchanger only partially. In addition, such Eritlüftungsöffnungen tend to noise, which is particularly in heat exchangers, which are arranged in the vehicle interior or adjacent to the vehicle interior (such as radiators) is disadvantageous.

The DE 100 41 121 A1 discloses a heat exchanger having a flow and a return and at least one venting device, wherein the venting device is arranged at a distance from at least one return opening in the heat exchanger.

The present invention is therefore based on the object, a heat exchanger with at least one venting device such that the known problems in known prior art heat exchangers are at least partially eliminated or at least mitigated. In particular, it makes the invention the task, a To propose heat exchangers, which is simple and inexpensive to design and manufacture, and still allows the greatest possible ventilation without an excess of unwanted noise occurs.

The devices according to the independent claim solve these objects.

It is proposed to further develop a heat exchanger for at least one heat transport medium with at least one flow, at least one return and at least one venting device, that the venting device is spaced from at least one return opening in the heat exchanger. The venting device can in particular be designed as a recess, and according to the invention is embodied in a partition wall of the heat exchanger which is normally present anyway, preferably in an upper region of a partition wall. It has surprisingly been shown that such an arrangement of the ventilation device can ensure a particularly advantageous ventilation of the heat exchanger. Up to now it has been assumed that an arrangement of the venting devices in the immediate vicinity of the return line is advantageous since it allows the gas accumulations to be sucked off particularly effectively. Unexpectedly, however, this is not the case, since often also gas accumulations can form, which are at a distance from the return of the heat exchanger. The proposed arrangement of the venting device, it may be possible that such gas accumulations are effectively removed. It is advantageous if at least in the areas in which a particularly large gas accumulation occurs in each case at least one venting device is provided.

It is preferable to also form the ventilation device at a distance from at least one feed opening in the heat exchanger. In this proposed embodiment, in addition to the actual passage of the heat transfer medium through the heat exchanger a kind of additional "vent circuit" are created especially in the upper part of the radiator, which in particular passes through the critical areas of the heat exchanger and thereby vent the heat exchanger particularly effective. It is of course important to ensure that the throughput of this additional vent circuit selected relatively low so that the efficiency of the heat exchanger does not decrease significantly.

It is proposed that the distance between at least one ventilation device and at least one flow opening and / or between at least one ventilation device and at least one return opening is at least 10 mm, preferably at least 15 mm, particularly preferably at least 20 mm and in particular at least 25 mm. The proposed values have proved favorable. However, other numerical values are conceivable. In particular, even with other numerical data occurring in this document, at (half) intervals and discrete values, all numerical values are to be regarded as disclosed and applicable in any desired manner.

It also proves to be advantageous if at least one flow opening and at least one return opening are arranged adjacent to one another. This can ensure a compact construction and a simple assembly, but also a particularly effective ventilation.

Furthermore, it has proved to be advantageous if at least one venting device is arranged at a distance from the direct connecting path between at least one feed opening and at least one return opening. In particular, it may prove to be advantageous if the venting device is arranged as far as possible from the direct connection path between the feed opening and the return opening. With the aid of the proposed embodiment, it is possible to allow a larger part or essentially the entire area of the heat exchanger, in which gas accumulations can form, to flow through the already mentioned "venting circuit", so that a particularly effective venting is promoted.

It has been found that the invention can be used particularly advantageously in connection with vertically arranged heat exchangers with advantageously at least one, preferably overhead, coolant box. Particularly in such heat exchangers, gas accumulations are easily generated, which can be eliminated particularly effectively using the present invention.

It has also been shown that the invention is particularly effective in connection with heat exchangers, which have a UT deflection and / or are formed as a radiator. A UT deflection is a so-called downward deflection of the heat transport medium in depth. The "depth" refers to the direction of flow of the second fluid, in particular air to be heated for a vehicle interior.

A particularly advantageous embodiment of the proposed invention results when at least one venting device is designed in the form of one or more openings.

One or two openings, possibly also three, four, five or even more openings, have proved to be advantageous. The openings can have any shape. Circular, semicircular, lenticular, square, rectangular, concave, semi-lenticular and / or slot-like recesses (in each case horizontally, vertically and / or obliquely guided) have proved to be useful. Dimensions of up to 5 mm, preferably 1 to 4 mm, particularly preferably 2 to 3 mm, have proven to be typical sizes. However, in particular in the case of slits, lengths of 5 to 15 mm, preferably 6 to 12 mm, in particular 8 to 10 mm, may prove to be favorable.

It is also possible to make the openings as an expression, which is advantageously formed in a coolant box, preferably in an overhead coolant box of the heat exchanger. The openings are particularly preferably provided in a contact region between the partition wall and the coolant box wall, in particular in an overhead region of the coolant box. Also, the opening may be located in the region of an optionally existing connecting seam of the coolant box. With this design, it is possible that manufacturing steps can be saved and possibly unnecessary material loads can be reduced. Of course, a combination of an opening designed as an expression and a recess is also possible, in particular if these are adjacent to one another such that the common opening cross-section increases.

A further advantageous design may result if at least one ventilation device has at least one flow-limiting device, which is designed in particular as a baffle plate, as a tube, as a molded-on flange and / or as a hydrodynamic flow-limiting device. In general, the proposed radiator should, at least in areas where it can lead to gas accumulation, as possible no sharp edges and other construction geometries, which can lead to unwanted noise. The proposed development, the noise can be further reduced by the currents occurring in particular from the speed and / or throughput can be reduced. The term "hydrodynamic flow restricting device" is to be understood quite generally as meaning devices in which a hydrodynamic dynamic pressure of the heat transport medium flowing through the heat exchanger is used to limit other flow paths, in particular of the material flowing through the venting devices.

Furthermore, it may prove to be advantageous to design at least one ventilation device as an external ventilation device outside the heat exchanger body and / or the coolant reservoir. Here, the venting device can for example be arranged as far away from the passenger compartment or in areas where only a few noises occur or the resulting noise is transmitted to a reduced extent in the motor vehicle interior.

It is conceivable in this context to provide at least one external ventilation device in a possibly separately formed flange region. This flange region can be provided for example with a certain distance from the heat exchanger in the flow or return line. For radiators, this distance between flange and radiator - and thus the distance of the venting device to the radiator - is usually relatively small, and is usually 10-50 mm, e.g. 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 40 mm or 50 mm.

Furthermore, it is proposed to provide a coolant circuit with at least one heat exchanger according to one of the proposed embodiments. The coolant circuit has the corresponding advantages in analog form.

It is also proposed to provide an air treatment device for motor vehicles with at least one heat exchanger according to one of the aforementioned embodiments. The air treatment device, which may, for example, additionally comprise an evaporator for cooling incoming air, then has the described advantages in an analogous form.

It is also advantageous to further develop a heat exchanger, a coolant circuit or an air treatment device according to one of the above-described training possibilities that at least one venting device based on at least one assembly of the heat transport medium circuit and / or related to the entire heat transport medium cycle in the region of a geodetically locally high-level and / or essentially in the area of the geodesic highest place. The proposed device can be made particularly effective in this case.

Figur 1

einen Heizkörper zur Beheizung eines Kraftfahrzeuginnenraums in perspektivischer Ansicht;

Figur 2

einen schematischen Querschnitt durch den in Figur 1 gezeigten Heizkörper;

Figur 3A und 3B

mögliche Heizkörperflachrohre im Querschnitt;

Figur 4A bis 4L

Ausführungsbeispiele von Trennwänden mit unterschiedlichen Entlüftungsöffnungen in Draufsicht;

Figur 5

eine Prallplatte für eine Entlüftungsvorrichtung im Querschnitt;

Figur 6A und 6B

eine Ausnasung mit einer Entlüftungsvorrichtung in schematischer Ansicht bzw. im Querschnitt;

Figur 7

eine weitere Ausführungsform einer Entlüftungsvorrichtung;

Figur 8

einen Teil eines Heizkreislaufs mit Heizkörper und externer Entlüftungsvorrichtung in schematischer Ansicht;

Figur 9

einen schematischen Querschnitt durch einen mit einer Ausprägung versehenen Kühlmittelkasten.

In the following the invention will be explained in more detail with reference to the attached figures with reference to preferred embodiments. It shows:

FIG. 1

a radiator for heating a motor vehicle interior in a perspective view;

FIG. 2

a schematic cross section through the in FIG. 1 shown radiator;

FIGS. 3A and 3B

possible radiator flat tubes in cross section;

FIGS. 4A to 4L

Embodiments of partitions with different vents in plan view;

FIG. 5

a baffle plate for a venting device in cross section;

FIGS. 6A and 6B

a Ausnasung with a venting device in a schematic view or in cross section;

FIG. 7

another embodiment of a ventilation device;

FIG. 8

a part of a heating circuit with radiator and external ventilation device in a schematic view;

FIG. 9

a schematic cross section through a provided with a feature coolant box.

In FIG. 1 a radiator 1 known per se for heating air is shown, which in the present case is supplied to a motor vehicle interior. The flow direction of the air is in FIG. 1 schematically indicated by an arrow A. The air flow can be performed in any way in the cross-flow or in the countercurrent countercurrent. The illustrated radiator 1 is a standing arranged, so-called UT radiator. The radiator 1 has at its upper end 2 and its lower end 3 each have a coolant box 4, 5, which also serves as a manifold for the coolant flowing therethrough. The upper coolant box 4 is divided by a schematically indicated partition 6 in a front, the lead 9 adjacent front portion 7 and a rear, the return 10 having rear portion 8.

Between the upper coolant box 4 and the lower coolant box 5, a plurality of coolant tubes formed in the present case as flat tubes 11 are formed. Between the flat tubes 11 are each corrugated fins 12, which improve the heat transfer to the air flowing through A. The corrugated fins 12 may be provided in a conventional manner to improve the heat transfer to the air flowing through A with a structuring.

In FIG. 2 is the in FIG. 1 illustrated radiator 1 shown schematically in cross section to explain the way of flowing through the radiator 1 coolant in more detail.

At the front side 13 of the radiator 1, the coolant flows to the flow 9 via a flow opening 15 in the front part 7 of the upper coolant tank 4 a. As already explained, the coolant box 4 has a partition wall 6, which separates the coolant box 4 into a front region 7 and a rear region 8. Starting from the front region 7, the coolant flows along the direction of the arrow B through the front lying areas 13 of the flat tubes 11 toward the bottom 3 of the radiator 1. The flat tubes 11 are - as explained in more detail below - designed such that in the region of the flat tubes 11th essentially no flow transverse to the longitudinal extent of the flat tubes 11 takes place. At the lower end 3 of the radiator 1, the coolant exits from the front part 13 of the flat tubes 11 in the lower coolant box 5. In this coolant box 5, the coolant is deflected in the "depth" C and enters the rear portion 14 of the flat tubes 11, where it flows in the opposite direction D up 2 to the upper coolant box 4. The flow path is indicated by arrows C, D. After the coolant has been released from the rear portion 14 of the flat tubes 11 in the rear part 8 of the coolant box 4, it finally exits from the radiator 1 via the return opening 16 and is guided via the return line 10 to the other components of the refrigerant circuit, not shown here ,

In the FIGS. 3A and 3B For the sake of completeness, possible embodiments of flat tubes 11 are shown, as they are for the in the FIGS. 1 and 2 shown radiator 1 can be used. This in FIG. 3A shown flat tube 11 has a plurality of passages 17 for the coolant and can be prepared for example by extrusion.

This in FIG. 3B Flat tube 11 shown can be made for example by bending or forming and then welding or soldering a solder-plated sheet. This flat tube 11 is divided by a central web 19 into two separate chambers 18.

For example, after a longer standstill phase or even during operation of a heat exchanger, such as in the FIGS. 1 . 2 shown radiator 1, 4 gas bubbles can accumulate especially in the upper region 2 of the upper coolant box. In this case, in particular gas bubbles which form in the flow 9 facing the front part 7 of the coolant box 4, without corresponding ventilation devices not or hardly removed from this front portion 7 of the upper coolant box 4. The gas bubbles can disturb the function of the radiator 1. On the one hand, the flow cross section for the coolant flowing through can be narrowed in the front region 7 of the upper coolant box 4 for the coolant flowing through it, so that the heating power of the radiator 1 can decrease. In addition, there may be a different heat distribution along the radiator surface 20, which accordingly leads to a different heating of the air flowing through A, which is correspondingly disadvantageous.

In order to remove the accumulating in the upper coolant box 4 gas bubbles, therefore, suitable ventilation devices are provided.

In FIG. 4 For this purpose, several suitable, provided with appropriate ventilation devices partitions 6 are shown.

In FIG. 4A In this case, a partition wall 6 is first shown, which is formed continuously and, for example, in connection with an external ventilation device 21 (see FIG. 8 ) can be used. In the embodiments of partitions 6 according to the Figures 4B to 4L is the venting device, however, each executed in the form of a differently shaped recess 22.

In the FIGS. 4B to 4E the recesses 22 are formed as round, semicircular, oval or semi-oval recesses 22. Although only a single recess 22 is shown in the figures, it is also possible to provide a plurality of recesses, which are preferably arranged along the upper edge of the partition wall 6. Typical dimensions are 1, 2, 3 or 4 mm (round or half round) or 1, 2 or 3 mm for the shorter axis and 2, 3, 4 mm for the longer axis (oval or half oval) at.

In the Figures 4F and 4G are a rectangular or square recess 22 are provided. Here too, as described in the case of round, semicircular, oval or semi-oval recesses, a plurality of recesses 22 can also be provided, whereby different shapes can also be mixed. This naturally also includes the following exemplary embodiments. Typical dimensions for the long sides are 1, 2, 3 or 4 mm.

Of course, also conceivable in this context, n-angular recesses, especially triangles, in different position and orientation. For the number of corners, however, the values 5, 6, 7, 8, 9 and 10 have proven to be particularly useful. The n-comers can not be just regular (isosceles) n-comers, but arbitrary, general n-comers.

In FIG. 4H the recess is formed as a concave, lenticular formation 22, which may be particularly preferably formed in the radius region of the partition wall. The radius of the lens preferably corresponds essentially the radius of the partition. However, other radii - in extreme cases also a straight line - are conceivable in this context.

It is also possible, as in FIGS. 4I and 4J shown that only part of the lens after FIG. 4H is removed from the partition 6 and, for example, only the lower half ( Fig. 4I ) or the upper half ( Fig. 4J ) Will get removed.

Quite generally, it is also possible to make advantageous use of shapes which are composed of straight lines and / or optionally a plurality of bends with the same, different as well as varying radius, and are provided in different numbers and different orientations.

Of course, also possible slot-shaped recesses, as in FIGS. 4K and 4L is indicated. 1, 2, 3 or 4 mm are available as the slot width, and the lengths 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 mm. The in Figure 4K Of course, shown angle of 45 ° can take other values.

In general, a value of 1, 2, 3, 4 or 5 has proven particularly useful for the number of openings. The partition walls 6 provided with openings 22 can of course also be combined with external ventilation devices 21. It is also possible to combine different opening shapes 22 with each other.

In FIG. 9 a venting device is shown, which is designed as an expression 37 in the upper wall 39 of the upper coolant box 4. The expression 37 can be generated, for example, by deforming the wall 39. In the region of the expression 37 is an opening 38 between the partition wall 6 and the upper wall 39 of the coolant box 4. Due to the opening 38 is a connection between the front region 7 and rear area 8, through which accumulating gas bubbles can be removed.

For the dimensioning of the expression 37 or the resulting opening 38 between the coolant box wall 39 and partition 6, the above-mentioned preferred design proposals can be used in an analogous manner.

Im in FIG. 9 illustrated embodiment, the partition 6 in the region of the expression 37 of the upper wall 39 of the coolant box 4 no recess. Of course, it is possible to provide an additional opening in the partition 6 in this area.

In FIG. 5 a presently designed as a baffle plate 23 flow limiting device is shown. In this case, in the region of an opening formed in the partition 6 opening 22 a parallel to the partition wall 6 extending strip material 25 is arranged, which is held for example via a retaining web 24. It is also possible that in one or in both side regions of the baffle plate 23 side walls, not shown here are arranged, so that there is a total trough-like design of the baffle plate 23. It should be noted that the baffle plate 23, in particular when it is arranged in the rear region 8 of the upper coolant box 4, can also exploit a hydrodynamic backwater. This arises due to the emerging from the flat tubes 11 flow, which is indicated by an arrow E. An advantage of this flow E is that it depends on the coolant throughput through the radiator 1. In the case of a large coolant flow rate 1 results in a relatively high pressure difference between the flow 9 and return 10 and thus between the front part 7 and the rear part 8 of the upper coolant tank 4, which would have a correspondingly high throughput through the recess 22 to result. This high throughput can be alleviated by the described hydrodynamic effect become. In any case, with the aid of the baffle plate 23, the throughput through the recess 22 can be reduced, and thus, in particular, the speed of passing gas and / or coolant can be reduced. This can in particular have a noise-reducing effect.

In Figure 6A, 6B a further flow-limiting device in the form of a flange or a projection 26 is shown, at the lower end 27 of a venting device 28 is formed. Here too, advantages may arise, in particular due to the hydrodynamic effect which may occur, as described above. In addition, the projection 26 may possibly be produced in a particularly simple and cost-effective manner by deforming material processing of the partition wall 6.

In FIG. 7 is another conceivable embodiment of a flow-limiting device in the form of a centrally arranged with a recess (not visible in the figure) tube 29. The tube 29 is present in the form of a "twisted S" bent so that the inlet 31 horizontally, the outlet 32nd the tube 29, however, is vertical, so that hydrodynamic effects can be used particularly advantageous. To stabilize a holding web 30 may be provided for the tube 29.

In FIG. 8 Finally, a part of a cooling circuit is still sketched, in which an external ventilation device 21 is provided, which is presently arranged at the (possibly local) highest point 33 of the cooling circuit. The radiator 1 may be connected in any manner with (eg FIGS. 4B to 4L ) or without (according to FIG. 4A ) Inner venting devices may be formed. The external venting device 21 has in the present embodiment shown via a thin connecting channel 36 which connects the flow line 34 with the return line 35.

However, the flange can - as usual with radiators - even at a smaller distance, such as at a distance of 10-50 mm, be arranged by the radiator. Optionally, the flange may also be integrated in the radiator. As a rule, only the distance between the forward and / or return opening 15, 16 and the connecting channel 36 is essential.

Claims (15)

1. A heat exchanger (1) for at least one heat transport medium, with at least one feed (9), at least one return (10) and at least one ventilation device (21, 22, 38), the ventilation device (23, 36, 38) being arranged at a distance from at least one return opening (16) in the heat exchanger, characterized in that at least one ventilation device (22) is formed in a partition (6), preferably in an upper region (2) of a partition (6) of the heat exchanger (1).
2. The heat exchanger as claimed in claim 1, characterized in that the ventilation device (21, 22, 38) is formed at a distance from at least one feed opening (15) in the heat exchanger.
3. The heat exchanger as claimed in claim 1 or 2, characterized by a distance of at least 10 mm, preferably at least 15 mm, particularly preferably at least 20 mm, in particular at least 25 mm, between at least one ventilation device (21, 22, 38) and at least one feed opening (15) and/or between at least one ventilation device (21, 22, 38) and at least one return opening (16).
4. A heat exchanger as claimed in one of the preceding claims, characterized in that at least one feed opening (15) and at least one return opening (16) are arranged adjacent to each other.
5. A heat exchanger as claimed in one of the preceding claims, characterized in that at least one ventilation device (21, 22, 38) is arranged at a distance from the direct connecting section between at least one feed opening (15) and at least one return opening (16).
6. A heat exchanger as claimed in one of the preceding claims, which heat exchanger is designed as a heat exchanger (1) which is arranged upright and has, advantageously, at least one coolant tank (4) preferably located at the top (2).
7. A heat exchanger as claimed in one of the preceding claims, which heat exchanger has a bottom depth deflection (5) and/or is designed as a radiator (1).
8. A heat exchanger as claimed in one of the preceding claims, characterized in that at least one ventilation device (22, 38) is designed in the form of one or more openings.
9. A heat exchanger as claimed in one of the preceding claims, characterized in that at least one ventilation device (38) is formed in a coolant tank (4), preferably in a coolant tank (4) located at the top (2) of the heat exchanger (1).
10. A heat exchanger as claimed in one of the preceding claims, in which at least one ventilation device (22) has a flow-limiting means (23, 26, 29) which is designed, in particular, as a baffle (25), as a tube (29), as an integrally formed flange (26) and/or as a hydrodynamic flow-limiting means (F).
11. A heat exchanger as claimed in one of the preceding claims, characterized in that at least one ventilation device is designed as an external ventilation device (21) outside the heat exchanger body (1) and/or the coolant tank (4).
12. The heat exchanger as claimed in claim 11, characterized in that at least one external ventilation device is formed in a flange region (21) which is optionally formed separately.
13. A coolant circuit comprising at least one heat exchanger (1) as claimed in one of claims 1-11.
14. An air treatment device for motor vehicles, comprising at least one heat exchanger (1) as claimed in one of claims 1-12.
15. A heat exchanger, coolant circuit or air treatment device as claimed in one of the preceding claims, characterized in that at least one ventilation device (21, 22, 38) is formed with respect to at least one subassembly (1, 4) of the heat transport medium circuit and/or with respect to the entire heat transport medium circuit in the region of a location (33) mounted (2) at a geodetically locally high point and/or substantially in the region of the location (33) mounted at the geodetically highest point.

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