Internal combustion engine with an exhaust turbocharger and an exhaust-gas recirculation device

• US 6,672,061 B2
• Filed: 10/24/2002
• Issued: 01/06/2004
• Est. Priority Date: 10/25/2001
• Status: Expired due to Term

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: DaimlerChrysler AG (Mercedes-Benz Group AG)
• Inventors: Sumser, Siegfried, Schmid, Wolfram
• Primary Examiner(s): Denion, Thomas
• Assistant Examiner(s): TRIEU, THAI BA
• Application Number:
  US10/278,996
• Publication Number:
  US 20030154717A1
• Time in Patent Office: 439 Days
• Field of Search: F02/M 2.507, F02/D 2.300, F02/B 3.344, 606/052, 606/02, 415/157, 415/158, 123/568.17, 298/892
• US Class Current: 60/605.2
• CPC Class Codes: F02B 29/0406 Layout of the intake air cooling or coolant circuit
• CPC Class Codes: F02B 37/02 Gas passages between engine outlet and pump drive, e.g. reservoirs
• CPC Class Codes: F02B 37/025 Multiple scrolls or multiple gas passages guiding the gas to the pump drive
• CPC Class Codes: F02B 37/22 by varying cross-section of exhaust passages or air passages , e.g. by throttling turbine inlets or outlets or by varying effective number of guide conduits F02B37/24 takes precedence
• CPC Class Codes: F02B 37/24 by using pumps or turbines with adjustable guide vanes
• CPC Class Codes: F02C 1/08 Semi-closed cycles
• CPC Class Codes: F02C 6/12 Turbochargers, i.e. plants for augmenting mechanical power output of internal-combustion piston engines by increase of charge pressure
• CPC Class Codes: F02M 26/05 High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor
• CPC Class Codes: F02M 26/10 having means to increase the pressure difference between the exhaust and intake system, e.g. venturis, variable geometry turbines, check valves using pressure pulsations or throttles in the air intake or exhaust system
• CPC Class Codes: F02M 26/23 Layout, e.g. schematics
• CPC Class Codes: F02M 26/43 in which exhaust from only one cylinder or only a group of cylinders is directed to the intake of the engine
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An internal combustion engine with an exhaust turbocharger and an exhaust-gas recirculation device comprises a turbine, assigned to the exhaust turbocharger, in the exhaust section and a compressor in the intake duct, the turbine having at least two flow passages, via which exhaust gas can be fed to the turbine rotor. For the purpose of dimensioning the two flow passages, an asymmetry factor is determined as a function of the displacement of the internal combustion engine.

Claims

1. An internal combustion engine comprising:

an exhaust turbocharger including,

an exhaust turbine disposed in an exhaust section, the exhaust turbine having a choke line, a turbine rotor and two flow passages for feeding exhaust gas to the turbine rotor,

a compressor in an intake duct, and

an exhaust-gas recirculation device having a recirculation line disposed between one of the flow passages and the intake duct; and

wherein an asymmetry factor (F_Asym) defining the size ratio of the flow passages of the exhaust turbine satisfies the formula

2. The internal combustion engine according to claim 1, wherein the recirculation line is connected to the smaller of the flow passages.

3. The internal combustion engine according to claim 2, wherein the exhaust turbine includes a variable turbine geometry, by which an inlet flow cross section between one of the flow passages and the turbine rotor is adjusted.

4. The internal combustion engine according to claim 3, wherein the variable turbine geometry is disposed in the inlet flow cross section of the larger of the flow passages.

5. The internal combustion engine according to claim 4, comprising three flow passages with each of the two smaller passages, wherein the turbine throughput parameter (φ

_31,S) is determined in accordance with

6. The internal combustion engine according to claim 5, wherein the two smaller flow passages communicate with the exhaust-gas recirculation device.

7. The internal combustion engine according to claim 6, further comprising an adjustable throttling device disposed in the flow path between at least one of the two smaller flow passages and the exhaust-gas recirculation device.

8. The internal combustion engine according to claim 7, wherein the exhaust turbine has a blow-off device that bypasses the turbine rotor.

9. The internal combustion engine according to claim 8, wherein the blow-off device branches off from the smaller flow passage.

10. The internal combustion engine according to claim 1, further comprising two exhaust lines, wherein each exhaust line connects a bank of cylinders to each flow passage.

11. The internal combustion engine according to claim 1, wherein the exhaust turbine includes a variable turbine geometry, by which an inlet flow cross section between one of the flow passages and the turbine rotor is adjusted.

12. The internal combustion engine according to claim 11, wherein the variable turbine geometry is disposed in the inlet flow cross section of the larger of the flow passages.

13. The internal combustion engine according to claim 1, comprising three flow passages with each of the two smaller passages, wherein the turbine throughput parameter (φ

_31,S) is determined in accordance with

14. The internal combustion engine according to claim 13, wherein the two smaller flow passages communicate with the exhaust-gas recirculation device.

15. The internal combustion engine according to claim 14, further comprising an adjustable throttling device disposed in the flow path between at least one of the two smaller flow passages and the exhaust-gas recirculation device.

16. The internal combustion engine according to one of claim 1, wherein the exhaust turbine has a blow-off device that bypasses the turbine rotor.

17. The internal combustion engine according to claim 8, wherein the blow-off device branches off from the smaller flow passage.

18. The internal combustion engine according to claim 1, wherein φ

_31,S and φ

_32,S denote turbine throughput parameters of the smaller and larger of the flow passages, respectively.

19. A method of making an internal combustion engine that includes an exhaust turbocharger including an exhaust turbine disposed in an exhaust section, and a compressor disposed in an intake duct, wherein the exhaust turbine includes a choke line, a turbine rotor and two flow passages for feeding exhaust gas to the turbine rotor, wherein the engine further includes an exhaust-gas recirculation device having a recirculation line disposed between one of the flow passages and the intake duct, the method comprising:

determining an asymmetry factor (F_Asym), which defines the size ratio of the flow passages of the exhaust turbine, in accordance with the formula,

20. The method according to claim 19, further comprising connecting the recirculation line to the smaller of the flow passages.

21. The method according to claim 20, further comprising adjusting an inlet flow cross section between one of the flow passages and the turbine rotor using a variable turbine geometry of the exhaust turbine.

22. The method according to claim 21, further comprising disposing the variable turbine geometry in the inlet flow cross section of the larger of the flow passages.

23. The method according to claim 19, further comprising determining the turbine throughput parameter (φ

_31,S) in accordance with

24. The method according to claim 23, further comprising connecting the two smaller flow passages with the exhaust-gas recirculation device.

25. The method according to claim 19, further comprising disposing an adjustable throttling device in the flow path between at least one of the two smaller flow passages and the exhaust-gas recirculation device.