Turbomachine

• US 9,234,456 B2
• Filed: 12/03/2012
• Issued: 01/12/2016
• Est. Priority Date: 10/06/2009
• Status: Active Grant

• Current Assignee: Cummins Limited (Cummins Incorporated)
• Original Assignee: Cummins Limited (Cummins Incorporated)
• Inventors: Parker, John F., Holroyd, Robert L., Roberts, Tom J., McEwen, James Alexander, Denholm, Tim, Moore, Simon, Voong, Michael, Normington, Christopher, Vijayakumar, Arun, Garrett, Stephen
• Primary Examiner(s): Kershteyn, Igor
• Assistant Examiner(s): Lee, Jr., Woody A
• Application Number:
  US13/692,787
• Publication Number:
  US 20130315718A1
• Time in Patent Office: 1,135 Days
• Field of Search: 415/158, 415162-166, 415/194, 415/195, 415/202, 415/205
• US Class Current: 1/1
• CPC Class Codes: F01D 17/143 the shiftable member being a wall, or part thereof of a radial diffuser
• 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: F05D 2220/40 in turbochargers
• CPC Class Codes: F05D 2250/283 honeycomb
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Claims

1. A variable geometry turbine comprising:

a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining a volute and an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls, the annular inlet located in between the volute and the turbine wheel such that the annular inlet receives gas from said volute and directs it to the turbine wheel; and

a cylindrical sleeve axially movable parallel to the turbine axis across the annular inlet to vary the size of a gas flow path for gas from said volute through the inlet to the turbine wheel;

wherein the annular inlet is divided into at least two axially offset inlet passages to divide said gas flow path for gas from said volute into at least two axially offset ancillary gas flow paths to the turbine wheel, and

wherein the innermost diameter of the sleeve is greater than the inner diameter of the inlet passages.

2. A variable geometry turbine according to claim 1, wherein the innermost diameter of the sleeve is less than or substantially equal to the outer diameter of the inlet passages.

3. A variable geometry turbine according to claim 1, wherein the innermost diameter of the sleeve is greater than the outer diameter of the inlet passages.

4. A variable geometry turbine according to claim 1, wherein the sleeve is axially movable across the annular inlet in a direction towards the second inlet sidewall so as reduce the size of the gas flow path through the inlet, and wherein at least a portion of an end of the sleeve nearer to the first inlet sidewall than the second inlet sidewall is configured so as to be exposable to gases flowing through said annular inlet during use.

5. A variable geometry turbine according to claim 1, wherein the sleeve is axially movable across the annular inlet in a direction towards the second inlet sidewall so as reduce the size of the gas flow path through the inlet, and wherein at least a portion of an end of the sleeve nearer to the first inlet sidewall than the second inlet sidewall is configured so as to be located in between said first and second inlet sidewall during axial movement of the sleeve across the annular inlet.

6. A variable geometry turbine according to claim 1, wherein the sleeve possesses a small radial thickness.

7. A variable geometry turbine according to claim 1, wherein the sleeve possesses a radial thickness which is less than the axial width of the annular inlet.

8. A variable geometry turbine according to claim 1, wherein the annular inlet is divided into at least two axially offset inlet passages by at least one annular baffle axially spaced from the first and second inlet sidewalls.

9. A variable geometry turbine according to claim 8, wherein inlet vanes extend axially across at least one of the axially offset inlet passages.

10. A variable geometry turbine according to claim 9, wherein the minimum distance between a baffle and the turbine wheel is less than the minimum distance between an adjacent vane and the turbine wheel.

11. A variable geometry turbine according to claim 9, wherein the trailing edges of at least some of the vanes extending across one of the axially offset inlet passages lie on a different radius to the trailing edges of at least some of the vanes extending across another of the axially offset inlet passages.

12. A variable geometry turbine according to claim 1, wherein the annular inlet is divided into an annular array of substantially tubular inlet passages extending generally towards the turbine wheel, wherein the annular array of inlet passages comprises at least three axially offset inlet passages.