EXHAUST-GAS TURBOCHARGER

• US 20170107896A1
• Filed: 05/19/2015
• Published: 04/20/2017
• Est. Priority Date: 05/20/2014
• Status: Active Application

• Current Assignee: BorgWarner Incorporated
• Original Assignee: BorgWarner Incorporated
• Inventors: GUGAU, Marc, SCHERI, Alessio
• Granted Patent: US 10,280,833 B2
• Time in Patent Office: Days
• CPC Class Codes: F01D 25/24 Casings modified for heating or cooling F01D25/14; Casing parts, e.g. diaphragms, casing fastenings casings for rotary machines or engines in general F16M ; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045
• CPC Class Codes: F01D 5/048 Form or construction
• CPC Class Codes: F01D 5/14 Form or construction selecting particular materials, measures against erosion or corrosion F01D5/28
• CPC Class Codes: F02B 37/025 Multiple scrolls or multiple gas passages guiding the gas to the pump drive
• CPC Class Codes: F05D 2220/40 in turbochargers
• CPC Class Codes: F05D 2250/51 Inlet
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An exhaust-gas turbocharger, preferably for a passenger vehicle, including a turbine having a turbine wheel and a turbine housing. A number of S≧2 of channels are formed in the turbine housing and are intended for guiding the exhaust gas onto the turbine wheel. Each channel directs flow against the turbine wheel over the entire width of the latter, as seen in the axial direction, and over a segment, as seen in relation to the circumferential direction. The turbine wheel has a number of Z≧10 turbine blades. The turbine blades are defined in the faun of main blades and intermediate blades. The intermediate blades, at least at their hub-side ends, do not extend as far toward the turbine outlet, as seen in the axial direction, as the main blades.

Claims

1. An exhaust-gas gas turbocharger (1) comprising

a compressor (2) having a compressor wheel (3),

a turbine (4) having a turbine wheel (5) and a turbine housing (6),

a shaft (7), which connects the compressor wheel (3) to the turbine wheel (5), and

a number of S≧

2 of channels (13, 14), which are formed in the turbine housing (6) and are intended for guiding the exhaust gas onto the turbine wheel (5),

wherein an axial direction (8) is defined along the shaft (7), from the compressor (2) to the turbine (4), a radial direction (9) is defined perpendicularly to the axial direction (8), and a circumferential direction (10) is defined around the axial direction (8), counter to the direction of rotation of the turbine wheel (5),

wherein each channel (13, 14) directs flow against the turbine wheel (5) over the entire width of the latter, as seen in the axial direction (8), and over a segment, as seen in relation to the circumferential direction (10),

wherein the turbine wheel (5) comprises a number of Z≧

10 turbine blades (12), and

wherein the turbine blades (12) are defined in the form of main blades (22) and intermediate blades (23), wherein the intermediate blades (23), at least at their hub-side ends (24), do not extend as far toward the turbine outlet, as seen in the axial direction (8), as the main blades (22).

2. The exhaust-gas turbocharger according to claim 1, wherein an intermediate blade (23) is arranged in each case between two main blades (22).

3. The exhaust-gas gas turbocharger according to the preceding claims claim 1, wherein

radial inner side of each channel (13, 14) terminates with a tongue (17), and a neck cross-sectional surface area Al of the respective channel is defined at a tip (18) of the tongue (17), and

sub-surfaces (21) are defined between turbine-outlet-side edges (19) of the turbine blades (12), in particular of the main blades (22), and these sub-surfaces together give a narrowest flow-outlet cross-sectional surface area A2,

where A2/A1≧

S·

0.9, preferably A2/A1≧

S·

1.0.

4. The exhaust-gas turbocharger according to claim 3, wherein a turbine-wheel inlet diameter D is defined at the turbine wheel (5), as measured up to the radial ends of the turbine blades (12), in particular of the main blades (22), where S·

A1/D≦

15 mm, preferably S·

A1/D≦

12 mm.

5. The exhaust-gas gas turbocharger according to claim 1, wherein

a radial inner side of each channel (13, 14) terminates with a tongue (17) and associated tip (18),

and wherein the tip (18) of the tongue of one channel (13) forms a geometrical reference point and, starting from this reference point, the next channel (14) terminates at 360°

/S, as measured in the circumferential direction (10),

and wherein the tip (18) of the tongue of this next channel (14) is shortened by an angle α

in the circumferential direction (10), and

where (360°

/Z)−

5°

≧

α

≧

5°

.

6. The exhaust-gas turbocharger according to claim 1, wherein a dedicated volute (15, 16) is formed in the turbine housing (6) for each channel (13, 14), and wherein the volutes (15, 16) are offset through 360°

/S in the circumferential direction (10).

7. The exhaust-gas turbocharger according to claim 1, wherein at least one volute (15) is formed in the turbine housing (6), and wherein, in the volute (15), two channels (13, 14) are separated by a crosspiece (25), and therefore one channel (14) is arranged radially outside the other channel (13).