DE102011120168A1 - Compressor for supercharger used in e.g. diesel engine, has two adjusters respectively arranged in compressor wheel upstream and compressor wheel outlet, to influence flow parameters at compressor impeller and compressor wheel outlet - Google Patents

Abstract

The compressor (15) comprises a compressor wheel (25) and a compressor stator (24) formed out of the compressor wheel. A primary axial displaceable adjuster is arranged in upstream of the compressor wheel, for influencing the flow parameters at a compressor impeller. A secondary axial displaceable adjuster (22) is arranged at a compressor wheel outlet, for influencing the flow parameters at the compressor wheel outlet.

Description

The invention relates to a compressor for an exhaust gas turbocharger according to the preamble of claim 1.

The DE 10 2009 014 350 A1 relates to a compressor wheel for a compressor of an exhaust gas turbocharger having a plurality of vane elements with a respective outer contour having at least one length region whose center tangent in the compressor longitudinal direction forms an angle with an axis of rotation of the compressor wheel, the central tangent to the axis of rotation forming an angle in one region from 15 ° to 90 °, and a compressor for an exhaust gas turbocharger with a compressor housing, by means of which a compressor is received, wherein upstream of the compressor wheel, an axially displaceable adjusting device is provided by means of which flow parameters can be influenced at a Verdichterradeintritt.

The invention is based on the object to provide a comparison with the prior art improved compressor for an exhaust gas turbocharger.

With regard to the compressor for an exhaust gas turbocharger, the object is achieved by the features specified in claim 1.

Advantageous embodiments of the invention are the subject of the dependent claims.

When compressor for an exhaust gas turbocharger with a compressor and a compressor at least partially corresponding to the compressor molded compressor housing, wherein upstream of the compressor an axially displaceable adjusting device is arranged, by means of which flow parameters can be influenced at a Verdichterradeintritt, according to the invention at a Verdichterradaustritt another adjusting device arranged by means of which Flow parameters can be influenced on a Verdichterradaustritt. As a result, advantageously, a compressor map can be widened or broadened, so that a power output and / or a power development of a combustion engine coupled to the compressor is improved.

Particularly advantageously, the two adjusting devices are so mechanically, pneumatically, hydraulically and / or electrically coupled that they are actuated together by means of a single actuator. As a result, a number of parts and a complexity of the compressor is reduced.

Appropriately, an efficiency of the compressor and thus the entire exhaust gas turbocharger is improved.

By means of the compressor according to the invention a particularly efficient operation of a coupled and acted upon by the compressor with compressed fresh air combustion engine in a particularly large operating point spectrum and / or range allows, which is advantageously accompanied by a reduction of fuel consumption and thus with a reduction of pollutant emissions of the internal combustion engine.

Embodiments of the invention are explained in more detail below with reference to drawings.

Showing:

1 1 schematically shows a representation of an internal combustion engine with an exhaust gas recirculation and a two-stage charging system according to the prior art,

2 1 is a schematic longitudinal sectional view of a compressor according to the invention, wherein an adjusting device is arranged on the compressor wheel outlet in a first position;

3 1 is a schematic longitudinal sectional view of a compressor according to the invention, wherein an adjusting device is arranged on the compressor wheel outlet in a second position;

4 schematically a diagram of an opening characteristic of the adjusting devices on a Verdichterradaustritt and a Verdichterradeintritt and

5 schematically a representation of an internal combustion engine with an exhaust gas recirculation and a two-stage supercharging system by means of an exhaust gas turbocharger with a compressor according to the invention.

Corresponding parts are provided with the same reference numerals in all figures,

1 schematically shows a representation of an internal combustion engine 1 with an exhaust gas recirculation and a two-stage charging system according to the prior art.

Here is the internal combustion engine 1 preferably designed as a conventional internal combustion engine, for example as a conventional diesel or gasoline engine. The internal combustion engine 1 includes an inlet tract 2 and an exhaust tract 3 , This is the internal combustion engine 1 , in particular, not shown combustion chambers the internal combustion engine 1 , by means of the inlet tract 2 Supplied fresh air or a fresh air mixture and by means of the Auslasstraktes 3 becomes an exhaust gas from the internal combustion engine 1 , in particular from the combustion chambers of the internal combustion engine 1 , guided away.

The internal combustion engine 1 includes a conventional exhaust gas recirculation system with an exhaust gas recirculation cooler 4 and an exhaust gas recirculation valve 5 , By means of the exhaust gas recirculation system is exhaust gas from the exhaust tract 3 in the inlet tract 2 traceable, whereby a pollutant reduction, in particular a reduction of nitrogen oxides in the exhaust gas, can be achieved, which conventionally in particular in an internal combustion engine 1 arise with a direct fuel injection.

To increase a maximum deliverable engine torque of the internal combustion engine 1 the same is coupled with a two-stage supercharging system, which is a high-pressure turbocharger 6 and a low-pressure turbocharger 7 includes. On one exhaust side of the supercharger system is a high pressure turbine 8th of the high-pressure turbocharger 6 arranged, which via a piping according to a directional arrow 9 Exhaust gas is supplied, causing the high-pressure turbine 8th is driven by the flowing exhaust gas. The high pressure turbine 8th is by means of a bypass valve 10 controlled and / or regulated by the exhaust gas flow around, which means that depending on an operating point of the internal combustion engine 1 Exhaust gas at the high-pressure turbine 8th can be bypassed if their throughput limit is reached.

The same applies to the low-pressure turbocharger 7 the charging system, which on the exhaust side of the supercharger one of the high-pressure turbine 8th downstream low-pressure turbine 11 having, by means of another bypass valve 12 controlled and / or regulated by the exhaust gas can flow around. Downstream of the supercharging system, the exhaust gas flows on the exhaust side according to a directional arrow 13 further in, for example, not shown exhaust aftertreatment and / or sound damping devices.

On a fresh air side of the charging system is according to a directional arrow 14 Fresh air sucked from the environment and by means of a low-pressure compressor 15 of the low-pressure turbocharger 7 precompacted. The low pressure compressor 15 is doing about one in a housing of the low-pressure turbocharger 7 mounted shaft 16 from the low-pressure turbine 11 driven. In the flow direction of the pre-compressed fresh air is a high pressure compressor 17 of the high-pressure turbocharger 6 arranged, which via one in a housing of the high-pressure turbocharger 6 mounted shaft 18 from the high-pressure turbine 8th is driven. The high pressure compressor 17 is by means of a bypass valve 19 controlled and / or regulated by the fresh air flow around, wherein a control and / or regulation of such a flow of an operating condition of the internal combustion engine 1 and the high-pressure turbocharger 6 depends. The high pressure compressor 17 flows around, for example, if its throughput limit is reached.

In the flow direction of the pre-compressed fresh air after the high-pressure compressor 17 is a charge air cooler 20 provided, which lowers a temperature of the compressed air and thus a higher air density and thus an improved filling or delivery in the combustion chambers of the internal combustion engine 1 and a resulting higher engine torque of the internal combustion engine 1 allows.

Thus, in 1 an internal combustion engine 1 with a two-stage charging system according to the prior art, in which the by-passing of the high-pressure compressor 17 by means of the bypass valve 19 Unacceptable discontinuities of the supercharging system and thus also for operation of the internal combustion engine 1 can arise.

2 shows schematically and in sections a longitudinal section of a compressor according to the invention 21 , wherein an adjusting device 22 at the compressor wheel outlet 23 is arranged in a first position.

The compressor 21 is part of an exhaust gas turbocharger, not shown, and includes at least one compressor housing 24 and a compressor wheel 25 , Here is the compressor wheel 25 in the compressor housing 24 recorded and surrounded at least in sections. The compressor wheel 25 is coupled by means of a shaft, not shown, with an exhaust gas turbine of the exhaust gas turbocharger and is offset during operation of this in a rotation about an axis of rotation A.

The compressor wheel 25 includes a shaft section 26 , which is arranged on the shaft and a plurality of rotationally symmetrical about the shaft portion 26 arranged blade elements 27 , In this case, each blade element has 27 a conical outer contour 28 on, whose middle tangent 29 with the axis of rotation A of the compressor wheel 25 an angle α opens, which is advantageously in a range of 15 ° to 90 °, more preferably in the range of 25 ° to 50 °.

The conical outer contour 28 begins at a blade leading edge 30 , which is also referred to as Radeintrittskante, and extends in the axial direction of the blade element 27 ,

The conical outer contour 28 is in its middle area of the compressor housing 24 surrounded, which in this section corresponding to the conical outer contour 28 of the blade element 27 is trained.

At an initial area of the conical outer contour 28 , also as compressor wheel entry 36 denotes, is an axially displaceable adjusting device 31 arranged in the form of a cone slide, which is displaceable in the axial direction along the axis of rotation A. An inside edge 32 of the cone slide is designed such that it is in the region of the conical outer contour 28 of the blade element 27 parallel to this runs, which in one in the 2 by means of a solid line shown closed position of the adjustment 31 a parallel gap between the conical outer contour 28 and the edge 32 is present. Furthermore, the edge is used 32 for guiding a flow which is, for example, air and according to a direction of a directional arrow 33 in the compressor 21 flows in and in the region of the blade leading edge 30 in the compressor wheel 25 entry. The in the 2 shown shape of the edge 32 allows a flow area reduction in front of the blade leading edge 30 from which an acceleration of the incoming air results.

A stop area 34 of the compressor housing 24 is so corresponding to the adjustment 31 formed to a gap-free stop in the closed position of the adjustment 31 , in particular to avoid erroneous flows to achieve. In addition, the compressor housing has 24 a cylindrical sliding area 35 on, in which the adjusting device 31 is displaceable in the axial direction. To represent a reliable axial adjustment are relatively low geometric tolerances to the compressor housing 24 necessary.

Here is the stop area 34 designed and optimized so that from the stop area 34 shifted adjustment 31 when it is moved out of the closed position in an open position, still an acceleration of the flow can take place. In this case, such a closed position is shown by the dashed lines.

Because from a release of the initial area of the conical outer contour 27 by means of the adjusting device 31 larger recirculation flow areas over the conical outer contour 28 result is an optimization of the nozzle-shaped stop area 34 to strive for, which is achieved for example by means of the illustrated embodiment.

At one end of the conical outer contour 28 , also as a compressor wheel outlet 23 denotes, is the axially displaceable adjusting device 22 arranged in the form of a cone slide, which is displaceable in the axial direction along the axis of rotation A. An inside edge 37 the adjusting device 22 is designed such that it is in the area of the conical outer contour 28 of the blade element 27 parallel to this runs, which in one in the 2 illustrated closed position of the adjusting device 22 a parallel gap between the conical outer contour 28 and the edge 37 is present. Furthermore, the edge is used 37 for guiding a flow, which for example from the compressor wheel 25 flowing air is. In this position is a cross section of a diffuser area 38 of the compressor 21 reduced.

3 shows schematically and partially a longitudinal sectional view of the compressor 21 , wherein the adjusting device 22 at the compressor wheel outlet 23 is arranged in a second position. In this position is the entire cross section of the diffuser area 38 of the compressor 21 Approved.

The adjusting device 22 at the compressor wheel outlet 23 is axially adjustable and has such a radial extent in the diffuser area 38 in that on by means of an actuation of the adjustment 22 simultaneously with the compressor wheel outlet 38 a diffuser width is changeable and / or adjustable.

Thus, by means of the adjusting device 22 Flow parameters at the compressor wheel outlet 23 and by means of the adjusting device 31 Flow parameter at the compressor wheel inlet 36 influenced.

Here are the two adjusting devices 22 . 31 such mechanically, pneumatically, hydraulically and / or electrically coupled that they together by means of a single actuator 39 are operable. This actor 39 can be designed as a conventional electric motor or as a pneumatically and / or hydraulically adjustable pressure cell.

By a compressor according to the invention is thus an in 1 shown bypassing the high pressure compressor 17 avoided.

4 schematically shows a diagram of an opening characteristic of the adjusting devices 22 and 31 at the compressor wheel outlet 23 and at the compressor wheel entry 36 ,

This is an area-and-distance diagram of the two variable adjustment surfaces A1 of the compressor wheel entry 36 and A2 of the compressor wheel outlet 23 depending on the respective adjustment paths s _A1 and s _{A2 of} the adjusting devices 31 and 22 , The minimum adjustment surfaces A1 _min and A2 _min in the respective closed position of the adjusting devices 31 and 22 and the maximum adjustment surfaces in the opening position of adjusting 31 and 22 A1 _max and A2 _max are over a basic design of the compressor 21 established.

A coupling of the adjustment of the two adjustment surfaces A1 and A2 can be adjusted by means of the adjustment length L, from which the surface coupling of the two adjustment surfaces A1 and A2 begins. As can be seen from the diagram, the absolute displacement s _{A1 of} the adjusting device 31 preferably greater than adjustment s _{A2 of} the adjustment 22 , Thus, a basic adjustment by means of the actuator 39 the adjusting devices 31 assigned to the adjustment from the adjustment length L 22 at a so-called coupling point 40 actuated. The resulting fixed coupling of both adjusting devices 31 and 22 remains above the adjustment s _{A2 of} the adjustment 22 up to an anchor point 41 receive.

In the further opening of the adjusting device 31 the adjustment surface A2 _{max will} remain at its maximum value, as shown in the diagram.

It should be mentioned that the mapping shown in the diagram between A1 _min and A2 _min at Aktuierung both adjusting devices 31 and 22 a realization to noticeably larger area quotients A1 _min / A2 _min from the compressor wheel entry 36 to the compressor wheel outlet 23 , or an increased acceleration of the currents in the compressor wheel allows. Due to the variability, this design tendency with respect to the rigid compressor can also be maintained for the maximum position of the two cross sections A1 _max / A2 _max , which is the case with regard to the generated efficiency characteristic at different positions of the coupled adjusting devices 31 and 22 positively affects.

In a first embodiment, the two adjusting devices 22 and 31 a single coupling point 40 exhibit.

In an alternative embodiment, the two adjusting devices 22 and 31 variable arranged coupling points 40 exhibit.

In an advantageous embodiment variant comprises a coupling of the adjusting devices 22 and 31 a single translation.

In an alternative embodiment, a coupling of the adjusting devices 22 and 31 have a variably adjustable translation.

5 schematically shows a representation of an internal combustion engine 1 with an exhaust gas recirculation and a two-stage supercharging system by means of an exhaust gas turbocharger with a compressor according to the invention.

The corresponding in 5 illustrated embodiment substantially the in 1 illustrated embodiment with the difference that the high-pressure turbocharger 6 instead of the conventional high pressure compressor 17 a compressor according to the invention 21 having.

This is a conventional bypassing of the high pressure compressor 17 by means of the bypass valve 19 obsolete, whereby also the already mentioned problems of a bypassing, namely in the form of sealing problems and / or discontinuities in an operation of the supercharging system in relation to the internal combustion engine 1 , are avoided.

LIST OF REFERENCE NUMBERS

1

Internal combustion engine

2

inlet tract

3

outlet zone

4

Exhaust gas recirculation cooler

5

Exhaust gas recirculation valve

6

High-pressure turbocharger

7

Low-pressure turbocharger

8th

High-pressure turbine

9

arrow

10

Bypass valve

11

Low-pressure turbine

12

Bypass valve

13

arrow

14

arrow

15

Low-pressure compressor

16

wave

17

High-pressure compressors

18

wave

19

Bypass valve

20

Intercooler

21

compressor

22

adjustment

23

Compressor impeller outlet

24

compressor housing

25

compressor

26

shaft section

27

vane element

28

conical outer contour

29

middle tangent

30

Blade leading edge

31

adjustment

32

edge

34

stop area

35

sliding area

36

Verdichterradeintritt

37

edge

38

diffuser area

39

actuator

40

coupling point

41

anchorage point

α

angle

A

axis of rotation

A1 _mm , A2 _min

displacement surface

L

adjustment length

s _A1 , s _A2

adjustment

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009014350 A1 [0002]

Claims (9)

Compressor for an exhaust gas turbocharger with a compressor wheel ( 25 ) and at least partially corresponding to the compressor wheel ( 25 ) molded compressor housing ( 24 ), wherein upstream of the compressor wheel ( 25 ) an axially displaceable adjusting device ( 31 ) by means of which flow parameters enter at a compressor wheel ( 36 ) are influenced, characterized in that at a Verdichterradaustritt ( 23 ) a further adjusting device ( 22 ) is arranged, by means of which flow parameters at a compressor wheel outlet ( 23 ) can be influenced. Compressor according to claim 1, characterized in that the two adjusting devices ( 22 . 31 ) are mechanically, pneumatically, hydraulically and / or electrically coupled in such a way that they are jointly actuated by means of a single actuator ( 39 ) are operable. Compressor according to claim 2, characterized in that the actuator ( 39 ) is designed as an electric motor. Compressor according to claim 2, characterized in that the actuator ( 39 ) is designed as a pneumatically and / or hydraulically adjustable pressure cell. Compressor according to one of the preceding claims, characterized in that the two adjusting devices ( 22 . 31 ) a single coupling point ( 40 ) exhibit. Compressor according to one of claims 1 to 4, characterized in that the two adjusting devices ( 22 . 31 ) variable coupling points ( 40 ) exhibit. Compressor according to one of the preceding claims, characterized in that a coupling of the adjusting devices ( 22 . 31 ) comprises a single translation. Compressor according to one of claims 1 to 6, characterized in that a coupling of the adjusting devices ( 22 . 31 ) has a variably adjustable translation. Compressor according to one of the preceding claims, characterized in that the further adjusting device ( 22 ) at the compressor wheel outlet ( 23 ) is axially adjustable and such a radial expansion in a diffuser region ( 38 ) that simultaneously with the compressor wheel outlet ( 23 ) a diffuser width is changeable and / or adjustable.

Images