Exhaust gas recirculation system and method

Patent metadata

Field	Value
Publication number	US-9938935-B2
Application number	US-201615086618-A
Country	US
Kind code	B2
Filing date	Mar 31, 2016
Priority date	Jul 12, 2012
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

Various methods and systems are provided for an exhaust gas recirculation system. In one example, an exhaust gas recirculation cooler includes an exhaust gas inlet and an exhaust gas outlet spaced from the exhaust gas inlet; a plurality of cooling tubes disposed between the exhaust gas inlet and exhaust gas outlet; and a baffle positioned proximate to the exhaust gas inlet and interposed between the plurality of cooling tubes and the exhaust gas inlet, where the baffle directs exhaust gas entering the EGR cooler through the exhaust gas inlet to the plurality of cooling tubes in a defined path.

First claim

The invention claimed is:

1. An exhaust gas recirculation (EGR) cooler, comprising:
an exhaust gas inlet and an exhaust gas outlet spaced from the exhaust gas inlet;
a plurality of cooling tubes disposed between the exhaust gas inlet and exhaust gas outlet; and
a baffle positioned proximate to the exhaust gas inlet and interposed between the plurality of cooling tubes and the exhaust gas inlet, where the baffle is configured to direct exhaust gas entering the EGR cooler through the exhaust gas inlet to the plurality of cooling tubes in a defined path.

2. The EGR cooler of claim 1 , wherein the baffle is positioned between a sidewall of a housing of the EGR cooler and a first group of cooling tubes of the plurality of cooling tubes that is positioned proximate to the exhaust gas inlet.

3. The EGR cooler of claim 2 , wherein the plurality of cooling tubes further comprises a second group of cooling tubes positioned downstream from the first group of cooling tubes, relative to a direction of exhaust gas flow through the EGR cooler, and wherein the baffle is positioned between the inlet and the second group of cooling tubes and between the sidewall and the first group of cooling tubes.

4. The EGR cooler of claim 3 , wherein cooling tubes of the second group of cooling tubes are positioned behind, in a downstream direction, the baffle, and wherein there are no cooling tubes positioned within a space occupied by the baffle.

5. The EGR cooler of claim 2 , wherein the sidewall is a first sidewall of the housing, and wherein the baffle is a first baffle positioned between the first sidewall of the housing and the first group of cooling tubes and further comprising a second baffle positioned between a second sidewall of the housing and the first group of cooling tubes, where the second sidewall is positioned opposite the first sidewall across a central axis of the EGR cooler.

6. The EGR cooler of claim 1 , further comprising a tube sheet extending across the EGR cooler between opposite interior sidewalls of a housing of the EGR cooler, wherein ends of cooling tubes of the plurality of cooling tubes are arranged at the tube sheet.

7. The EGR cooler of claim 6 , further comprising a welded seam between a first beveled edge of an interior sidewall of the housing and a second beveled edge of the tube sheet.

8. The EGR cooler of claim 7 , wherein the first beveled edge is at an angle of about 45 degrees and the second beveled edge is at an angle of about 25 degrees.

9. The EGR cooler of claim 1 , further comprising a plurality of fins positioned between cooling tubes of plurality of cooling tubes, wherein a fin density of the plurality of fins is smaller proximate to an interior sidewall of a housing of the EGR cooler than at a center of the EGR cooler.

10. The EGR cooler of claim 9 , wherein the fin density proximate to the exhaust gas inlet and the interior sidewall is less than 50% of a fin density proximate to the exhaust gas outlet.

11. The EGR cooler of claim 1 , further comprising exterior baffles extending around an outer perimeter of a housing of the EGR cooler and spaced apart from one another, wherein a sealing material is included around an outer perimeter of the exterior baffles, wherein each exterior baffle of the exterior baffles includes a polymeric sealing material positioned around an entire outer perimeter of the exterior baffle.

12. The EGR cooler of claim 11 , wherein the sealing material is fluoropolymer including an alternating copolymer of tetrafluoroethylene and propylene.

13. The EGR cooler of claim 11 , further comprising at least one aperture arranged in one or more of the exterior baffles, sized and shaped to provide a drain rate of under 15 minutes.

14. The EGR cooler of claim 1 , further comprising a coolant inlet fluidly coupled with the plurality of cooling tubes and arranged at a bottom of the EGR cooler and a coolant outlet fluidly coupled with the plurality of cooling tubes and arranged at a top of the EGR cooler, wherein coolant passes through the cooling tubes from the coolant inlet to the coolant outlet.

15. An exhaust gas recirculation (EGR) cooler, comprising:
a plurality of cooling tubes disposed between an exhaust inlet and outlet of the EGR cooler; and
a housing surrounding and enclosing the plurality of cooling tubes within the EGR cooler, the housing including a plurality of exterior baffles spaced apart from one another along a length of the EGR cooler, in a direction of exhaust flow through the EGR cooler, each exterior baffle of the plurality of exterior baffles extending around an entire outer perimeter of the housing and including a polymeric sealing material positioned around an entire outer perimeter of the exterior baffle.

16. The EGR cooler of claim 15 , wherein the plurality of cooling tubes are grouped into a plurality of bundle groups of multiple cooling tubes and wherein each exterior baffle of the plurality of exterior baffles is positioned between adjacent bundle groups or between one of the bundle groups and one of the exhaust inlet or outlet.

17. The EGR cooler of claim 15 , where the polymeric sealing material is a fluoropolymer including an alternating copolymer of tetrafluoroethylene and propylene.

18. An exhaust gas recirculation (EGR) cooler, comprising:
a plurality of cooling tubes disposed between an exhaust inlet and outlet of the EGR cooler and enclosed within a housing of the EGR cooler, where a first group of the plurality of cooling tubes is positioned proximate to the exhaust inlet and a second group of the plurality of cooling tubes is positioned adjacent to and downstream of the first group, the first group and the second group each positioned between opposite sidewalls of the housing; and
a first baffle positioned between a first sidewall of the housing and the first group and a second baffle positioned between a second sidewall of the housing and the first group, where edges of the first baffle and second baffle are positioned forward of the second group relative to the exhaust inlet.

19. The EGR cooler of claim 18 , wherein a width of the first group, between an outermost tube of the first group on a first side of the first group and an outermost tube of the first group on a second side of the first group, the second side opposite the first side, is narrower than a width of the second group.

20. The EGR cooler of claim 18 , wherein a region of the EGR cooler including the first baffle and second baffle contains no cooling tubes.

Assignees

• Gen Electric

Inventors

• Bailey Kevin Paul
• Peters Eric David
• Prechtl Ian
• Lee Justin
• Lossie Jared
• Karmakar Uday Prakash
• Jayakar Vijayaselvan
• Wright David

Classifications

• F02M26/11

  Manufacture or assembly of EGR systems; Materials or coatings specially adapted for EGR systems · CPC title

• F01P7/16

  by thermostatic control · CPC title

• F02M26/14

  in relation to the exhaust system · CPC title

• F01P2050/06

  using liquid-to-liquid heat exchangers · CPC title

• F01P2060/16

  Outlet manifold · CPC title