Exhaust-gas heat exchanger

Patent metadata

Field	Value
Publication number	US-2015152762-A1
Application number	US-201314371455-A
Country	US
Kind code	A1
Filing date	Aug 26, 2013
Priority date	Aug 28, 2012
Publication date	Jun 4, 2015
Grant date	—

Abstract

An exhaust-gas heat exchanger for an exhaust system for cooling an exhaust-gas flow, having an inner pipe and an outer pipe, wherein the two pipes are indirectly or directly welded to one another in sealing fashion at the inlet side, a jacket pipe is arranged around the outside of the outer pipe and an annular gap for coolant is arranged between the outer pipe and the jacket pipe, and the inner pipe has an axial flow cross section (A 2 ) at the end as viewed in the flow direction (S) and has a perforation (P 2 ), which forms a radial flow cross section, in a direction at right angles to a flow direction (S). Between the inner pipe and the outer pipe there is formed an exhaust-gas duct for the exhaust-gas flow, wherein an intermediate pipe which is mounted in displaceable and/or rotatable fashion on the inner pipe is provided with a perforation (P 4 ) by which the axial flow cross section (A 2 ) of the inner pipe can be at least partially closed off.

First claim

What is claimed is:

1 . An exhaust-gas heat exchanger for an exhaust system for cooling an exhaust-gas flow comprising: an inner pipe and an outer pipe, wherein
a) the two pipes are indirectly or directly welded to one another in sealing fashion at an inlet side, b) between the inner pipe and the outer pipe there is formed an exhaust-gas duct for the exhaust-gas flow, c) a jacket pipe is arranged around an outside of the outer pipe and an annular gap for coolant is arranged between the outer pipe and the jacket pipe, and d) the inner pipe has a perforation (P 2 ) with an equivalent radial flow cross section in a direction at right angles to a flow direction (S) and an opening with an axial flow cross section (A 2 ) at the end as viewed in the flow direction (S), e) an intermediate pipe with a perforation (P 4 ) is provided on the inner pipe such that it can be displaced or rotated, and the perforation forms an equivalent radial flow cross section, and f) the intermediate pipe can at least partly close off the perforation (P 2 ) of the inner pipe and alter the radial flow cross section.

2 . The exhaust-gas heat exchanger according to claim 1 , wherein the opening can be at least partly closed off by an adjustable device and the axial flow cross section (A 2 ) can be altered.

3 . The exhaust-gas heat exchanger according to claim 1 , wherein the axial flow cross section (A 2 ) of the opening and the radial flow cross section of the perforation (P 2 ) of the inner pipe can be changed at the same time.

4 . The exhaust-gas heat exchanger according to claim 1 , wherein the perforation (P 4 ) of the intermediate pipe at least partly overlaps with the perforation (P 2 ) of the inner pipe and/or the two radial flow cross sections are identical.

5 . The exhaust-gas heat exchanger according to claim 1 , wherein the intermediate pipe can rotate about a center axis (M) and/or shift in the direction of the center axis (M).

6 . The exhaust-gas heat exchanger according to claim 1 , wherein the device and the intermediate pipe are configured as a subassembly, and a switching element is provided, by which the intermediate pipe and the device can be moved at the same time.

7 . The exhaust-gas heat exchanger according to claim 1 , wherein the radial flow cross section as the sum of the areas of all holes forming the perforation (P 2 ) of the inner pipe corresponds at least to 1.2 to 1.7 times the axial flow cross section (A 2 ) of the inner pipe.

8 . The exhaust-gas heat exchanger according to claim 6 , wherein the switching element can be controlled actively or passively by an exhaust-gas back pressure created by the exhaust-gas flow or by an actuator.

9 . A system consisting of an exhaust-gas heat exchanger according to claim 1 and an exhaust system or other subassemblies of an exhaust system for an internal combustion engine and/or for a motor vehicle.

10 . A method for regulating an exhaust-gas flow in an exhaust-gas heat exchanger in an exhaust system, wherein the exhaust-gas heat exchanger has an inner pipe and an intermediate pipe mounted on the inner pipe, the inner pipe and the intermediate pipe each have a perforation (P 2 , P 4 ) with a radial flow cross section in a radial direction of a center axis (M), comprising the steps of mounting the intermediate pipe so that it can rotate or move relative to the inner pipe and regulating the quantity of the exhaust-gas flow that flows in the radial direction through the perforation (P 2 ) of the inner pipe in the direction of an exhaust-gas duct by moving the intermediate pipe.

11 . The method according to claim 10 , wherein the quantity of the exhaust-gas flow which flows in the axial direction through the opening of the inner pipe arranged downstream from the perforation (P 2 ) in the flow direction (S) is regulated by moving a device, wherein the intermediate pipe and the device are moved at the same time.

12 . The exhaust-gas heat exchanger according to claim 2 , wherein the perforation (P 4 ) of the intermediate pipe at least partly overlaps with the perforation (P 2 ) of the inner pipe and/or the two radial flow cross sections are identical.

13 . The exhaust-gas heat exchanger according to claim 12 , wherein the intermediate pipe can rotate about a center axis (M) and/or shift in the direction of the center axis (M).

14 . The exhaust-gas heat exchanger according to claim 13 , wherein the device and the intermediate pipe are configured as a subassembly, and a switching element is provided, by which the intermediate pipe and the device can be moved at the same time.

15 . The exhaust-gas heat exchanger according to claim 14 , wherein the radial flow cross section as the sum of the areas of all holes forming the perforation (P 2 ) of the inner pipe corresponds at least to 1.2 to 1.7 times the axial flow cross section (A 2 ) of the inner pipe.

16 . The exhaust-gas heat exchanger according to claim 15 , wherein the switching element can be controlled actively or passively by an exhaust-gas back pressure created by the exhaust-gas flow or by an actuator.

17 . A system consisting of an exhaust-gas heat exchanger according to claim 16 , and an exhaust system or other subassemblies of an exhaust system for an internal combustion engine and/or for a motor vehicle.

Assignees

• Tenneco Gmbh

Inventors

• Geminn Markus
• Steigert Andreas
• Roth Margit
• Womann Marcel
• Jochem Alexander

Classifications

• F02M26/00

  Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems · CPC title

• F01N5/02 Primary

  the devices using heat · CPC title

• F28F27/02

  for controlling the distribution of heat-exchange media between different channels ({static flow control means in header boxes F28F9/026}; arrangements of guide plates or guide vanes F28F9/22, F28F25/12) · CPC title

• F01N2260/024

  using a liquid · CPC title

• F01N2240/36

  an exhaust flap · CPC title