Turbocharger combining axial flow turbine with a compressor stage utilizing active casing treatment

Patent metadata

Field	Value
Publication number	US-2016160756-A1
Application number	US-201414904716-A
Country	US
Kind code	A1
Filing date	Jul 17, 2014
Priority date	Jul 24, 2013
Publication date	Jun 9, 2016
Grant date	—

Abstract

A turbocharger ( 1 ) with an axial flow turbine ( 2 ) includes a compressor stage ( 4 ) using active casing treatment ( 50 ) for choke flow improvement. With switchable slots ( 52, 54 ), one of the slots ( 52 ) may be between the compressors full and splitter blades ( 27, 23 ) and one of the slots ( 54 ) can be located downstream of the compressors splitter blades ( 23 ) to maximize choke flow capacity. In turbochargers with a wastegate assembly, an actuator ( 32 ) may control both a wastegate control valve ( 30 ) and an active casing treatment slot selection valve ( 56 ).

First claim

What is claimed is:

1 . A turbocharger ( 1 ) comprising a turbine stage ( 2 ) and a compressor stage ( 4 ), the turbine stage ( 2 ) including a turbine wheel ( 16 ) selected from the group consisting of an axial flow turbine wheel and a mixed-flow turbine wheel, the compressor stage ( 4 ) including
a compressor housing ( 20 ), and a compressor wheel ( 28 ) disposed in the compressor housing ( 20 ) and connected to the turbine wheel ( 16 ) via a shaft ( 18 ), wherein the compressor housing ( 20 ) includes active casing treatment ( 50 ) that is configured to control air flow to the compressor wheel ( 28 ).

2 . The turbocharger ( 1 ) of claim 1 , wherein a ratio of the size of the compressor wheel ( 28 ) to the size of the turbine wheel ( 16 ) is in a range of 0.95:1.00 to 1.05:1.00.

3 . The turbocharger ( 1 ) of claim 1 , wherein a ratio of the size of the compressor wheel ( 28 ) to the size of the turbine wheel ( 16 ) is 1.00:1.00.

4 . The turbocharger ( 1 ) of claim 1 , wherein a Blade Speed Ratio of the turbocharger ( 1 ), defined as U/Co, is in a range of 0.75 to 0.90.

5 . The turbocharger ( 1 ) of claim 1 wherein active casing treatment ( 50 ) comprises a slot ( 52 , 54 ) formed in the compressor inlet wall, the slot ( 52 , 54 ) opening facing the compressor wheel ( 28 ) and configured to selectively circulate air relative to the compressor wheel ( 28 ).

6 . The turbocharger ( 1 ) of claim 1 wherein active casing treatment ( 50 ) comprises
a first slot ( 52 ) formed in the compressor inlet ( 22 ) wall, the first slot ( 52 ) opening facing the compressor wheel ( 28 ) at a first location,
a second slot ( 54 ) formed in the compressor inlet ( 22 ) wall, the second slot ( 54 ) opening facing the compressor wheel ( 28 ) at a second location,
a slot selection valve ( 56 ) configured to control gas flow to the first slot ( 52 ) and the second slot ( 54 ), and to permit selection between using the first slot ( 52 ) and using the second slot ( 54 ).

7 . The turbocharger ( 1 ) of claim 6 wherein the second location comprises a location downstream of a leading edge ( 21 ) of splitter blades ( 23 ) of the compressor wheel ( 28 ).

8 . The turbocharger ( 1 ) of claim 6 wherein the first location comprises a location between a leading edge ( 25 ) of full blades ( 27 ) of the compressor wheel ( 28 ) and a leading edge ( 21 ) of splitter blades ( 23 ) of the compressor wheel ( 28 ).

9 . The turbocharger ( 1 ) of claim 6 , wherein the turbine stage ( 2 ) comprises a wastegate valve ( 30 ) and the turbocharger ( 1 ) includes a single actuator ( 32 ) configured to control both the position of the wastegate valve ( 30 ) and the slot selection valve ( 56 ).

10 . The turbocharger ( 1 ) of claim 1 , wherein the turbine wheel ( 16 ) is an axial flow turbine wheel.

Assignees

• Borgwarner Inc

Inventors

• Mcgahey Michael
• Ausbrooks Michael

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02C6/12 Primary

  Turbochargers, i.e. plants for augmenting mechanical power output of internal-combustion piston engines by increase of charge pressure · CPC title

• F02B37/183 Primary

  Arrangements of bypass valves or actuators therefor · CPC title

• F05D2220/40

  in turbochargers · CPC title

• F04D27/0207

  by bleeding, bypassing or recycling fluids (influencing the boundary layer by an uncontrolled bleeding of the working fluid F04D29/681) · CPC title