DE2342787A1 - CROSS FLOW HEAT EXCHANGER, IN PARTICULAR INTERCOOLER FOR CHARGED COMBUSTION MACHINES - Google Patents

Description

A KHD

Ktöckner Humboldt OeutzAG ZA |% JHI) O 5 Cologne 80, to Aug. 17, 1973

Our trainer: D 73/71 APTB Ν / Β

Cross-flow heat exchangers, in particular charge air coolers for supercharged internal combustion engines

The invention relates to a cross-flow heat exchanger, in particular a charge air cooler for supercharged internal combustion engines, in which the coolant by means of tubes, in particular finned tubes, which are arranged in rows one behind the other, through the air flow is directed.

It is known (US Pat. No. 3,232,042) to use the intercooler as a finned tube cooler train and use water as a coolant. In such intercoolers, all pipes have the same length, the same diameter and the same cooling surface. Furthermore, the air speed is over the entire cooling depth, i.e. over practically constant over the entire path that the air travels through the cooler. The row of pipes that is the first with the one to be cooled The medium, in this case the charge air, comes into contact with the highest thermal load. The temperature of the coolant rises therefore it is highest in these pipes. If, for example, seawater is used as the cooling medium, this temperature increase can occur lead to the precipitation of hardness builders and salts, which ultimately leads to the failure of the heat exchanger.

It is therefore the object of the present invention to provide a cross-flow heat exchanger to improve the above type with simple means so that the disadvantages described are avoided and

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and the operational reliability of the heat exchanger even with sea or Raw water is guaranteed.

This object of the invention is achieved in that the tubes are arranged and / or designed in such a way that the heat exchange occurs increased in the direction of the air flow. The fact that now in the first or the first rows of tubes is not the optimal possible amount of heat is transferred from the air to the cooling water, the heating of the same in these cooling pipes is so far reduces that no precipitation of hardness builders and salts takes place. The heat exchange can only take place in the following pipes then be increased to the respective optimum, since at this point in time the charge air has already cooled down so far that a Overheating of the cooling water is no longer to be feared. Because the fins on cooling tubes make a significant contribution to heat exchange supply, it is proposed that the number of fins per tube increases in the direction of the air flow. Can have a similar effect can also be achieved in that the height of the ribs of the tubes increases in the direction of the air flow. Particularly easy and inexpensive the effect according to the invention can be achieved in that at least the first row of tubes seen in the air direction has no ribs is executed. In the case of particularly high charging of the internal combustion engine and, as a result, high charge air temperature, it can be useful be that at least the first row of tubes seen in the air direction has an insulation. A similar effect on the Heat exchange like the size and arrangement of fins also has the flow velocity or the impact velocity of the

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Cooling medium ». Therefore, it is proposed in a further embodiment of the invention that the heat exchanger has side walls, the Distance from one another decreases in the direction of the air flow.

For further explanation of the invention, reference is made to the drawing, in which five exemplary embodiments of the invention are shown in simplified form. Show it:
Fig. 1 shows a partial section through a finned tube charge air cooler, parallel to the tubes, in which, according to the invention, the distance between the ribs is greater for the first two rows of tubes than for the subsequent tubes,

Fig. 2 a partial cross-section through a finned tube charge air cooler, in which the first two rows of tubes are designed without ribs,

Fig. 3 shows a partial cross-section according to Fig. 2, in which the pipes of the first two rows of pipes have a greater distance from one another than the pipes of the next pipe rows, Fig. 4 shows a partial cross-section according to Fig. 2, in which the distance between the side walls of the intercooler is in Air direction reduced ,
Fig. 5 shows a partial cross-section according to Fig. 2, in which the pipes of the first two rows of pipes are provided with insulation.

In the figures, 1 denotes a charge air cooler which has a larger number of tubes 2 which, as can be seen in particular in FIG. 1, are fastened in a sealing manner in end plates 3.

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Cooling water flows through the pipes, not shown in detail and thus cool the air flow represented by arrow 4. This airflow is undesirable through the charge fan heated and rope cooled to the intake organs of the internal combustion engine stream. Furthermore, with the exception of some of FIG. 2, all tubes have cooling fins 5, which facilitate the exchange of heat between cooling water and increase air.

As can be seen in particular from Fig. 1, the cooling fins 5 on the two rows of tubes, the arrow 4 and thus the air flow are closest, a greater distance from each other than the fins of the remaining tubes.

In Fig. 2, however, the two seen in the direction of arrow 4 are The tubes arranged in the first rows of tubes are designed without ribs.

Another embodiment is provided in Fig. 3, in which the tubes 2, which are closest to the air flow, have a larger one The distance from one another is indicated by the arrow 4 and thus the air flow facing away rows of tubes.

In Fig. 4, the intercooler has side walls 6, as a modification of the previous embodiments, through which the cross section tapers in the direction of arrow 4.

Finally, in Fig. 5, all tubes 2 and the ribs 5 are evenly formed and distributed, but the tubes have the

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seen in the direction of arrow 4 first two rows of pipes insulating layers that reduce the heat transfer between air and coolant. The insulating layer can, for example consist of plastic plastic.

All of these embodiments are based on the idea of a 2U strong heat exchange in the. To prevent the first row of tubes, so that excessive heating of the cooling water is avoided.

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Claims (7)

5 Cologne 80, August 17, 1973
Unsar characters: D 73/71 APTB N / B Claims (I. / Cross-flow heat exchanger, in particular charge air cooler for supercharged internal combustion engines, in which the coolant is by means of
Pipes, especially finned pipes, laid out in rows one behind the other
are arranged through which the air flow is passed, characterized in that the tubes (2) are arranged and / or designed in such a way that the heat exchange increases in the direction of the air flow (4). 2. Cross-flow heat exchanger according to claim 1, characterized in that that the number of ribs (5) per tube (2) increases in the direction of the air flow "(4). 3. Cross-flow heat exchanger according to claim 1, characterized in that that the height of the ribs (5) of the tubes (2) increases in the direction of the air flow (4). 4. Cross-flow heat exchanger according to claim 1, characterized in that that at least the first row of tubes seen in the air direction is designed without ribs. 5. Cross-flow heat exchanger according to claim 1, characterized in that that at least the first row of tubes seen in the air direction has insulation. 5 0 9 8 10/0 50 A BATH ORIGINAL - 7 - 17 Aug 1973 D 73/71 6. Cross-flow heat exchanger according to claim 1, characterized in that that the heat exchanger (1) has side walls (6) whose distance from one another decreases in the direction of the air flow (4). 7. Cross-flow heat exchanger according to claim 1, characterized in that that the distance between the tubes (2) is reduced in the direction of the air flow ^ · (4). 509810/0504 Blank page