Nozzled turbine

Patent metadata

Field	Value
Publication number	US-9157396-B2
Application number	US-201313896488-A
Country	US
Kind code	B2
Filing date	May 17, 2013
Priority date	May 17, 2013
Publication date	Oct 13, 2015
Grant date	Oct 13, 2015

Abstract

A turbine includes a turbine housing having two gas passages of substantially the same flow area. A nozzle ring is disposed in the housing and around the turbine wheel. The nozzle ring includes first and second outer rings, and an inner ring disposed between the first and second outer rings. First and second pluralities of vanes are disposed between the rings. The second outer ring has a thicker cross section than the first outer ring such that a larger flow area is created between the first outer ring and the inner ring than a flow area created between the second outer ring and the inner ring.

First claim

We claim:

1. A nozzle ring adapted for installation into a receiving bore in a turbine housing, the turbine housing having two flow passages having the same flow area formed therewithin and separated by a divider wall, each flow passage being connected to a respective gas inlet, the receiving bore surrounding a turbine wheel when the turbine housing is assembled into a turbocharger, the nozzle ring comprising:
a first outer ring;
an inner ring disposed adjacent the first outer ring, said inner ring having an annular shape and disposed in axial alignment with the divider wall,
a second outer ring disposed adjacent the inner ring, said second outer ring having a thicker cross section than the first outer ring;
a first plurality of vanes fixedly disposed between the first outer ring and the inner ring, the first plurality of vanes defining a first plurality of inlet openings therebetween that are in fluid communication with a slot formed in the nozzle ring and adapted to surround the turbine wheel;
a second plurality of vanes fixedly disposed between the second outer and the inner rings, the second plurality of vanes defining a second plurality of inlet openings therebetween that are in fluid communication with the slot;
wherein the first plurality of inlet openings collectively defines a first flow outlet area that is larger than a second flow outlet area collectively defined by the second plurality of inlet openings.

2. The nozzle ring of claim 1 ,
wherein each of the first plurality of inlet openings defines a respective first throat area, which represents a minimum cross-sectional flow area of the respective first inlet opening, and a respective first outlet area, which is defined at a boundary between the respective first inlet opening and the slot;
wherein each respective first throat area is equal to each respective first outlet area;
wherein each of the second plurality of inlet openings defines a respective second throat area, which represents a minimum cross-sectional flow area of the respective second inlet opening, and a respective second outlet area, which is defined at a boundary between the respective second inlet opening and the slot; and
wherein each respective second throat area is equal to each respective second outlet area.

3. The nozzle ring of claim 1 , wherein the first plurality of inlet openings is functionally equal to a first nozzle of a converging/diverging type, the first nozzle having a first throat area and a first outlet area, and wherein the second plurality of inlet openings is functionally equal to a second nozzle of a converging/diverging type, the second nozzle having a second throat area and a second outlet area.

4. The nozzle ring of claim 1 , wherein, when the nozzle ring is installed in the turbine housing and the turbocharger is operating, the nozzle ring operates to align a gas flow passing therethrough into a flow having only radial and tangential components with respect to the turbine wheel.

5. The nozzle ring of claim 1 , wherein the thicker cross section of the second outer ring contributes to increasing efficiency of the turbocharger by being disposed in a flow path of exhaust gas passing through the nozzle ring so that a flow diffusion thereof is controlled before the exhaust gas reaches the turbine wheel.

6. A turbine, comprising:
a turbine housing including at least two gas passages having the same flow area and disposed on opposing sides of a divider wall;
a turbine wheel having a plurality of blades;
a nozzle ring connected to the turbine housing and disposed around the turbine wheel, the nozzle ring having:
a first outer ring,
an inner ring disposed adjacent the first outer ring, said inner ring having an annular shape and disposed in axial alignment with the divider wall,
a second outer ring disposed adjacent the inner ring, said second outer ring having a thicker cross section than the first outer ring;

a first plurality of vanes fixedly disposed between the first outer and the inner rings, the first plurality of vanes defining a first plurality of inlet openings therebetween that are in fluid communication with a slot formed in the nozzle ring and surrounding the turbine wheel;
a second plurality of vanes fixedly disposed between the second outer and the inner rings, the second plurality of vanes defining a second plurality of inlet openings therebetween that are in fluid communication with the slot;
wherein the first plurality of inlet openings collectively defines a first flow outlet area that is larger than a second flow outlet area collectively defined by the second plurality of inlet openings.

7. The turbine of claim 6 ,
wherein each of the first plurality of inlet openings defines a respective first throat area, which represents a minimum cross-sectional flow area of the respective first inlet opening, and a respective first outlet area, which is defined at a boundary between the respective first inlet opening and the slot;
wherein each respective first throat area is equal to each respective first outlet area;
wherein each of the second plurality of inlet openings defines a respective second throat area, which represents a minimum cross-sectional flow area of the respective second inlet opening, and a respective second outlet area, which is defined at a boundary between the respective second inlet opening and the slot; and
wherein each respective second throat area is equal to each respective second outlet area.

8. The turbine of claim 6 , wherein, during operation, a first portion of exhaust gas flow entering the turbine housing passes through the first plurality of inlet openings and a second portion of exhaust flow entering the turbine housing passes through the second plurality of inlet openings, and wherein a variation of a ratio between the first and second portions of exhaust gas flow is less than 5% when a speed of the exhaust gas passing through the first and second pluralities of inlet openings changes from subsonic to supersonic and vice versa.

9. The turbine of claim 8 , wherein the first flow outlet area is equal to a first nozzle of a converging/diverging type, the first nozzle having a first throat area and a first outlet area, and wherein the second flow outlet area is equal to a second nozzle of a converging/diverging type, the second nozzle having a second throat area and a second outlet area.

10. The turbine of claim 9 , wherein the first portion of exhaust gas flow depends on a size of the first outlet area when the speed of the exhaust gas flow is subsonic and on a size of the first throat area when the speed of the exhaust gas flow is supersonic.

11. The turbine of claim 10 , wherein the first throat area is 940 square millimeters, and wherein the second throat area is 406 square millimeters.

12. The turbine of claim 6 , wherein each of the first and second pluralities of vanes includes 15 vanes.

13. The turbine of claim 6 , further including a smooth protrusion connected to the second outer ring and extending peripherally around the second outer ring along a sidewall thereof facing the inner ring, such that the smooth protrusion is disposed within and encroaches into a cross sectional flow area between the inner ring and the second outer ring.

14. The turbine of claim 6 , wherein the nozzle ring is disposed within a bore formed in the turbine housing, and wherein the turbine further includes a retainer disposed to retain the nozzle ring within the bore of the housing, the retainer extending peripherally around the nozzle ring and connected to the housing by fasteners.

15. An internal combustion engine, comprising:

Assignees

• Caterpillar Inc

Inventors

• Lusardi Christopher
• Kruiswyk Richard W
• Delvecchio Kerry A
• Wolk Matthew T
• Swar Rohan
• Hergart Carl-Anders

Classifications

• F01D9/04 Primary

  forming ring or sector · CPC title

• F01D9/026 Primary

  Scrolls for radial machines or engines · CPC title

• F01D9/045

  for radial flow machines or engines · CPC title

• F01D9/047

  Nozzle boxes · CPC title

• F02M25/0707 Primary

  Mechanical Engineering · mapped topic