DE102006056774A1 - Heat exchanger e.g. cooling liquid heat exchanger for use in motor vehicle, has tubes interacting with openings of collecting tank and header tank such that end of each tube has contour - Google Patents

Abstract

The heat exchanger comprises tubes (11) made of sheet-metal strip, for regulating the temperature of a medium such as coolant and charge air flowing through the tubes. The ends of the tubes interact with the openings (23) in a collecting tank (24), header tank (25) such that end (21) of each tube has a contour (220). Independent claims are included for the following: (1) cooling liquid heat exchanger; and (2) heat exchange liquid heat exchanger.

Description

The The invention relates to a cooling liquid cooler, the flat tubes and interposed ribs having a cooling power form and of cooling air flows through be to cool the flowing in the flat tubes cooling liquid, wherein the Ends of flat tubes with openings in collection boxes or with openings in tube sheets, those with the collection boxes are connected, cooperate, and with at least one partition in one of the collection boxes, about yourself that of cooling air be streamed area of the cooling network and over a part of the cooling network depth extending low-temperature current and one in the flow direction the cooling air seen behind it high-temperature current in the cooling liquid cooler produce.

The closest prior art known to the Applicant, having the said features, may be the WO 02/48516 A1 be removed. There, the coolant flow is already divided into two streams before entry into the inlet header of the cooler, which are then "converted" into a low-temperature stream and a high-temperature stream, so to speak, by means of partitions in the inlet box as well In the discharge box, some of them are diverted several times in order to obtain certain desired temperature differences between the streams, but the cooler is rather complicated to produce due to the numerous dividing walls not negligible pressure loss of the coolant.

These disadvantages may also be said to the heat exchanger, which from the WO 03/046457 A1 is known, although with this heat exchanger considerable temperature differences will be feasible. There, the number of partitions and the deflections is apparently even greater. In addition, this heat exchanger lacks the above-mentioned feature, according to which the low-temperature region or the regions or the currents should extend beyond the flowed-on surface of the cooling network. Since partitions are present in both header boxes, a part of the streamlined cooling surface area is occupied by a high-temperature stream and another part of the streamlined cooling network area is occupied by a low-temperature stream.

The latter also applies to the integrated heat exchanger of FR 2 682 160 is known. There, the low-temperature region is located laterally next to the high-temperature region, so there is also the flowed-cooling surface, as described, divided, which, moreover, apparently the 4 and 5 from the WO 02/48516 A1 which, however, is much younger than the FR'160. Finally, this also applies to the Kühlflüssigkeitkühler from the WO 98/12425 is known. There, the low temperature range is below the high temperature range.

In former times, two separate coolers have often been provided, with one cooler providing a higher temperature coolant flow and the separate cooler or subcooler providing a lower temperature coolant flow. An example of this construction goes from the EP 54 792 A2 out.

The The object of the invention is in the structural simplification of initially described Kühlflüssigkeitkühlers, without its effectiveness over fee to worsen.

The solution according to the invention itself with a Kühlflüssigkeitkühler, the all Features of claim 1.

It is envisaged that the collecting box constituting the entrance collecting box is formed without inner partition, that one or more longitudinal partition walls are located in the collecting box constituting the discharge header box, and that the streams from the inlet header box to the outlet header box pass through the flat tubes in a common direction. According to this proposal, in contrast to WO 02/48516 A1 - The division of the cooling liquid flow in at least two streams, which have different temperatures after leaving the Kühlflüssskühlers made in the cooling liquid cooler itself. Quite surprisingly, in automotive coolant coolers equipped with these features, it has been found that temperature differences can be achieved between the currents, which are in the range of +/- 10 K, which is sufficient for many applications. From the features listed itself it follows that the cooling liquid cooler according to the invention has been significantly simplified compared to the above-mentioned prior art, which leads to a reduction in construction costs. For example, this is completely dispensed with transverse partitions. There is no partition in the entrance collection box. In the exit collection box there are only longitudinal partitions, usually one is sufficient. This makes the structural simplification clear. In some applications, there are two spaced-apart and preferably parallel-running longitudinal partitions.

In these cases, two low-temperature currents can then be achieved. The terms "longitudinal" and "transverse" refer to the longitudinal direction of the header regardless of how the coolant flows sigkeitskühler is arranged in the motor vehicle. The achievement of the set goal is also supported by the fact that the flat tubes are arranged and formed in a single row of flat multi-chamber tubes, because this measure also simplifies the cooling liquid cooler. Since deflections of the cooling liquid, in particular countercurrent within the cooling network is completely dispensed with, the pressure drop is comparatively very low, which will make itself noticeable in particular in the energy consumption of the coolant pump.

It it is provided that at the outlet collecting box at least two outlet openings are present, through which the currents with different temperatures the cooler leave. In the entry collection box, a single opening is sufficient, in preferably the entire coolant flow - to each Case, but the largest share of the same - occurs, which, however, does not rule out that the coolant flow through several openings could enter the undivided entry collection box.

The are flat tubes of the coolant radiator, as mentioned above, flat multi-chamber tubes with two narrow sides and two broad sides, which are arranged in a single row. This applies regardless of the depth of the cooling network. Thus, the Multi-chamber pipes Depth dimensions or dimensions of their in cooling air flow direction have extending broad sides, for example, between 20 and 300 mm. With particular preference are the multi-chamber pipes made of at least one formed sheet metal strip, the Thickness is in the range of 0.03 to 0.20 mm. A very special advantageous multi-chamber tube is made of three metal strips, wherein two metal strips form the wall of the multi-chamber tube and the third corrugated sheet metal strip forms an inner insert, the forming the chambers of the pipe. These features also contribute to reduce the construction costs and beyond that is due to the extreme low wall thickness the heat exchange efficiency positively influenced.

The Invention will be described below in embodiments with reference to FIG attached Drawings described. The figures show the following:

1 Front view of a coolant radiator in principle;

1a Side view of it;

2 Front view of another coolant radiator in principle;

3 Cross section of a preferred flat multi-chamber tube of the Kühlflüssigkeitskühlers;

4 and 5 Cooling circuits with cooling liquid cooler;

6 - 8th Presentation of examination results;

9 Section of a radiator;

The coolant cooler has flat tubes 1 and intervening ribs which together form the cooling network 3 form. The cooling air flows through the ribs 2 to those in the flat tubes 1 to cool flowing coolant. The ends of the flat tubes 1 flow into an entry collection box 4E and at the opposite end into an exit collection box 4A , The 1 and 2 show a view of the cooled air flow on the side of the cooling liquid cooler. In the 2 became the area of the cooling network that was affected by the cooling air 3 with a dashed line and denoted by A. It is the entire cooling grid area. The entire cooling liquid flow to be cooled passes through an opening 41 in the entry collection box 4E one. In the 2 owns the exit collection box 4A a single longitudinal partition 5L , as in the example 4 as a simple stroke 5L was drawn. With this one longitudinal partition 5L A low-temperature current NT and a high-temperature current HT, both of which form the outlet box, are set 4A via one opening each 40 leave. In contrast, the Kühlflüssigkeitkühler from the 1 and 1a two parallel longitudinal partitions 5L why two low-temperature currents NT1 and NT2 are formed there. The collection boxes 4 are preferably made of plastic and the longitudinal partition wall / walls 5L is / are an integral part of the collection boxes, which also increases the stability without causing extraordinary costs. The cooling liquid cooler in the 5 on the other hand has three longitudinal partitions 5L , with the result that another NT3 current can be formed. The cooling network depth T was in the 3 and 4 located. The longitudinal partitions 5L are arranged so that each current NT, HT occupies a certain proportion of the cooling network depth T. The currents NT, HT flow through the cooling network 3 parallel and in a common direction from the entry collection box 4E to the exit collection box 4A what the arrows in the 1 . 2 . 4 and 5 to show. It should be clear to the extent that at the Kühlluftanströmseite A must be the most cooled stream NT, since there the highest temperature difference between the cooling air and the cooling liquid is present. In order for the NT and HT streams to develop, either an extra series of flat tubes must be assigned to each NT, HT stream, or it must be one single row of multi-chamber pipes 1M can be used, which extends over all streams NT, HT. The latter measure is particularly preferred because it contributes to the structural simplification. The multi-chamber pipes 1M have dimensions of their in the cooling air flow direction extending broadsides 11 , which are, for example, between 20 and 300 mm, which corresponds to possible depth dimensions T of the cooling network.

The flat multi-chamber pipes in the coolant cooler 1M as components of the cooling network 3 are produced according to a very particularly preferred embodiment of three transformed endless metal strips a, b, and c. The metal strips a and b are formed identically, wherein the one longitudinal edge of the metal strip was provided with a larger arc than the other longitudinal edge. The two metal strips a, b are then arranged to each other so that the larger arc of a sheet metal strip engages around the smaller arc of the other metal strip to the two narrow sides 10 of the multi-chamber tube 1M to form, like that in the 3 you can see. It can also be seen there that the third sheet-metal strip c is formed with a corrugation which forms the chambers K of the multi-chamber tube 1M form. The corrugated metal strip c is inserted in the course of the merger of the pipe wall forming sheet metal strips a and b therebetween. The longitudinal edges of the metal strip c were also formed and lie inside in the narrow sides 10 of the multi-chamber tube 1M to reinforce them clearly. The thickness d of the tube wall forming sheet metal strips a and b is approximately between 0.06 mm and 0.20 mm and the thickness of the metal strip c, which forms the inner insert is between 0.03 mm and 0.10 mm. Because of the extremely small sheet thicknesses d are two stable narrow sides 10 of the multi-chamber tube 1M of special interest.

From the simplified cooling circuit according to the 4 shows that the low-temperature current NT is used for example for transmission oil cooling GÖK. The high-temperature current HT is used mainly for cooling the drive motor of the motor vehicle. In the cooling circuit according to the 5 Other cooling requirements are covered with several NT circuits. For example, one NT current can be used together to cool electronic components and oil. Another NT power is used for indirect intercooling. Another NT power can be used for heat exchange with the refrigerant of an air conditioner, or even serve other purposes.

With The described design of the coolant radiator temperature differences between the NT current and the HT current are generated, which are approximately at 7-11 K.

In addition, the inventors have dealt with the questions to what extent you can meet fluctuating cooling requirements even better and where the optimal position of the longitudinal partitions 5L should lie. First, they provide the possibility of forming the flow velocity v in the NT flow identical to that in the HT flow. As a result, despite the provision of a low-temperature current, the provided cooling capacity of the coolant radiator can be utilized. However, it is also possible to install flow resistances with which the flow velocities v can be influenced within certain limits. ( 7 and 8th ) In the 4 W indicated a flow resistance in the NT flow. It is a throttle or the like. The same can then be provided in the HT stream. This can be better respond to certain operating situations of the motor vehicle, the fluctuating cooling requirements by itself.

The 6 shows results of investigations of how the temperature curves in the streams adjust when the position of the longitudinal dividing wall 5L is changed. The investigations were carried out with a cooling network 3 depth T of about 55 mm, which was plotted on the abscissa. On the right ordinate the cooling power in KW was plotted and on the left ordinate the temperature of the coolant. The curves show the temperature curve in the NT and HT flow as a function of the position of the longitudinal dividing wall 5L , For example, there is a longitudinal partition wall 5L at 40 mm for the HT flow and thus at 15 mm for the NT flow, an exit temperature of about 78 ° C in the HT flow and about 68 ° C in the NT flow. Under the boundary conditions specified there: Cooling air temperature about 29.5 ° C, mass flow about 6.61 kg / s, coolant inlet temperature 97 ° C etc.

The 9 shows the pipe ends of the cooling network 3 from multi-chamber pipes 1M and corrugated ribs 2 , The pipe ends are stuck in openings 45 a collection box 4 or a tube bottom. As can be seen from the illustration, has the collection box / tube bottom 4 a roughly semicircular contour. In any case, the pipe ends do not protrude inwards in order to avoid unnecessary pressure loss in the cooling liquid. The top part of the collecting tank 4 was not drawn. It is also about half-round, so that a round or oval cross-section of the collecting tank 4 present, which has a good pressure stability.

Claims (10)

Coolant cooler, the flat tubes ( 1 ) and intervening ribs ( 2 ) having a cooling network ( 3 ) and are traversed by cooling air to those in the flat tubes ( 1 ) cooling coolant, the ends of the flat tubes ( 1 ) with openings in collecting boxes ( 4 ) or with openings in tubesheets which are connected to the collecting tanks ( 4 ), cooperate, and with at least one partition wall ( 5 ) in the collecting box in order to obtain a surface (A) of the cooling network which is flown by cooling air ( 3 ) and a part of the cooling network depth (T) extending low-temperature current (NT) and seen in the flow direction of the cooling air, behind it high-temperature current (HT) to produce in the cooling liquid cooler, characterized in that the collecting box ( 4 ), which holds the entry collection box ( 4E ) is formed without partition that is one or more longitudinal partitions ( 5L ) in the exit collection box ( 4A ), and that the streams (NT, HT) from the collection box ( 4E ) to the exit collection box ( 4A ) in a common direction through the flat tubes ( 1 ) to run. Coolant radiator according to claim 1, characterized in that the flat tubes ( 1 ) in a single row of flat multi-chamber tubes ( 1M ) are arranged and formed. Coolant radiator according to claim 1, characterized in that the flat tubes ( 1 ) in several rows in the cooling network ( 3 ), each row being associated with a stream (NT or HT). Coolant radiator according to claims 1, 2 or 3, characterized in that at the outlet collecting box ( 4A ) at least two outlet openings ( 40 ) are present, through which the streams (NT; HT) leave the cooler at different temperatures. Coolant radiator according to one of the preceding claims, characterized in that at the entry collection box ( 4E ) an entrance opening ( 41 ) is present to accommodate at least most of the total cooling liquid flow. Coolant cooler after one of the preceding claims, characterized in that a plurality of low-temperature currents (NT1, NT2 ...) are formed next to the high-temperature current (HT). Coolant cooler according to claims 1 and 2, characterized in that the flat multi-chamber tubes (IM) have two narrow sides ( 10 ) and two broadsides ( 11 ) and can be produced by forming at least one endless metal strip whose thickness (d) is approximately between 0.03-0.20 mm. Coolant radiator according to claims 1, 2 and 7, characterized in that the multi-chamber tubes ( 1M ) are produced from three endless sheet metal strips (a, b, c), wherein two sheet metal strips (a, b) form the wall of the tube and wherein the third sheet metal strip (c) is a corrugated inner insert, whereby the chambers (K) of the multi-chamber tube ( IM) are formed. Cooling liquid cooler according to claims 1, 2, 7 and 8, characterized in that the sheet metal strips (a, b) are formed identically, wherein the one longitudinal edge of the sheet metal strips (a, b) was equipped with a larger arc as the other longitudinal edge, wherein the two sheet-metal strips (a, b) are arranged relative to one another in such a way that the larger arc of one sheet metal strip engages around the smaller sheet of the other sheet-metal strip, around the two narrow sides ( 10 ) of the multi-chamber tube ( 1M ) to build. Coolant radiator according to one of the preceding claims, characterized in that the multi-chamber tubes ( 1M ) Have dimensions of their extending in the cooling air flow direction broadsides, which are between 20 and 300 mm, what possible depth dimensions (T) of the cooling network ( 3 ) corresponds.