TUBE, IN PARTICULAR A FLAT TUBE FOR AN EXHAUST GAS COOLER AND EXHAUST GAS COOLER

Abstract

A tube (10) for an exhaust gas cooler comprises at least two projections (14), developed on the inside, of which at least one, implemented closer to the gas inlet, is developed lower in the direction toward the tube axis than at least one that is implemented closer to the gas outlet.

An exhaust gas cooler comprises at least one such tube.

Claims

1.-9. (canceled)

10. A tube for an exhaust gas cooler comprising: at least two projections on an inside thereof, wherein one of the projections is implemented closer to a gas inlet in the direction toward the gas inlet, is developed lower in the direction of a tube axis than at least one implemented closer to a gas outlet, wherein the tube is flat.

11. A tube according to claim 10, wherein the projection in the direction toward the tube axis become continuously higher/deeper, wherein directly adjacent projections are, as needed, developed of identical height/depth.

12. A tube according to claim 10, wherein this tube comprises in cross section two parallel side walls on each of which projections are developed.

13. A tube according to claim 10, wherein the projections are developed such that they are elongated.

14. A tube according to claim 10, wherein the projections extend at an angle to the direction of flow.

15. A tube according to claim 12, wherein the projections developed on opposing sides criss-cross.

16. A tube according to claim 10, wherein the projections have a height/depth of 1 to 40%, preferably 10 to 30%, of the height of the tube.

17. A tube according to claim 10, wherein, apart from the projections, the tube has a constant flow cross section.

18. A tube according to claim 11, wherein this tube comprises in cross section two parallel side walls on each of which projections are developed.

19. A tube according to claim 11, wherein the projections are developed such that they are elongated.

20. A tube according to claim 12, wherein the projections are developed such that they are elongated.

21. A tube according to claim 11, wherein the projections extend at an angle to the direction of flow.

22. A tube according to claim 12, wherein the projections extend at an angle to the direction of flow.

23. A tube according to claim 13, wherein the projections extend at an angle to the direction of flow.

24. A tube according to claim 13, wherein the projections developed on opposing sides criss-cross.

25. A tube according to claim 14, wherein the projections developed on opposing sides criss-cross.

26. A tube according to claim 11, wherein the projections have a height/depth of 1 to 40%, preferably 10 to 30%, of the height of the tube.

27. A tube according to claim 12, wherein the projections have a height/depth of 1 to 40%, preferably 10 to 30%, of the height of the tube.

28. A tube according to claim 13, wherein the projections have a height/depth of 1 to 40%, preferably 10 to 30%, of the height of the tube.

29. Exhaust gas cooler comprising at least one tube according to claim 10.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0015] In the following a preferred embodiment example of the invention is described in greater detail with reference to the Figures. In the drawing depict:

[0016] FIG. 1 a perspective view of a flat tube according to the invention;

[0017] FIG. 2 a cross sectional view of the flat tube according to FIG. 1;

[0018] FIG. 3 a sectional view A-A according to FIG. 2 of the flat tube of FIGS. 1 and 2 in the proximity B of FIG. 1; and

[0019] FIG. 4 a sectional view A-A according to FIG. 2 of the flat tube of FIGS. 1 and 2 in the proximity of C of FIG. 1.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0020] As shown in FIG. 1, the linear flat tube 10 according to the invention has a constant wall thickness over its length and, on its outerside, comprises numerous elongated indentations 12 that extend at an angle, for example of 40 to 50, to the tube axis. Each of the indentations 12 has a substantially strip-shaped bottom toward which all transitions from the outer tube surface are radiused.

[0021] As is especially clearly shown in FIG. 2, these indentations developed on the tube outerside form on the innerside numerous projections 14, that have a certain height/depth, wherein said bottom of each indentation forms on the tube innerside a surficial face of the projection, which extends substantially parallel to the tube axis. In the direction of the tube axis the projections have substantially a width that corresponds substantially to the distance between two projections. The projection seen in FIG. 2 of the projections 14 in the direction of the tube axis corresponds substantially to the width seen in FIG. 2 of flat tube 10 without the rounded side sections. Projections 14 are developed obliquely toward the tube axis or, viewed on the inside, minimally concavely. Over their predominant width seen in FIG. 2 their respective bottoms are parallel with respect to one another and to the upper and lower delimitation of the flat tube 10.

[0022] In FIG. 3 can be seen especially clearly each of the radiused transitions from the tube outside to the projection and back to the tube outerside. It further is evident in FIG. 3 that the projections of opposing tube walls are developed such that they criss-cross as viewed from above or below and do not oppose each other exactly but are minimally offset with respect to one another in the direction of the tube axis.

[0023] Based on the comparison of FIGS. 3 and 4, it can be seen that the height/depth of the projections increases in the direction toward the tube outlet. According to the flow direction D of the gas in FIG. 1, in FIG. 3 the region B of the tube outlet is shown in which the projections have a height/depth X of approximately 30% of that in FIGS. 3 and 4 evident from top to bottom of the height of the tube. In the proximity of tube inlet C shown in FIG. 4, this height/depth Y is 10 to 20% of the height of the tube. Stated differently, X is according to the invention greater than Y. The upper and lower tube wall evident in FIGS. 3 and 4 is on the sides, not evident in FIGS. 3 and 4, that is on the cut-away side directed toward the viewer, and on the side directed away from the viewer connected by substantially semi-cylindrical sections (cf. in this connection FIG. 2).