Compressor Assembly for a Turbocharger

Abstract

The present invention relates to a compressor assembly for a turbocharger.

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a compressor assembly. In addition, the scope of the present invention also extends to compressors having a purely radial or diagonal outflow from the compressor impeller. Furthermore, the present invention relates to a turbocharger with a compressor assembly.

PRIOR ART

In order to improve the load response behavior in the case of turbocharged internal combustion engines, air injection systems are used in and downstream of the turbocharger compressor. Such a known air injection system consists of what are referred to as auxiliary air drives. Compressed air is injected here in the impeller region of the compressor and in the direction of rotation. As a result, the compressor rotor blades are driven and the rotational speed of the turbocharger and also the mass flow and the charging pressure ratio increase. Another known air injection system is known under the name direct air injection system (DAI system). In this case, compressed air is injected coaxially into the pipe downstream of the compressor outlet flange via what is referred to as a lance. The system operates here in the manner of a jet pump, that is to say, it reduces the compressor outlet pressure, and therefore the turbocharger rapid reaches a higher speed of rotation. At the same time, the mass flow through the engine is thus increased, which permits a more rapid load response. DAI systems which are known from the prior art and have an air injection device are generally designed here in such a manner that a nozzle projects into the flow channel of the diffuser in or downstream of the turbocharger compressor. Other known DAI systems provide the use of what are referred to as annular chamber arrangements in the flow channel. However, this has the following disadvantages: firstly, flow losses may occur during operation because of the nozzle projecting into the flow channel. Also, because of the flow in the flow channel, the risk of breakage of a nozzle increases when the nozzle projects into the flow channel. When an annular chamber arrangement is used in the flow channel, an additional component is required, which causes additional costs.

SUMMARY OF THE INVENTION

The present invention is based on the objective technical object of developing a compressor assembly with an injection system in such a manner that optimized injection of fluid into the flow channel of the compressor assembly is ensured and at the same time flow losses in the flow channel of the compressor assembly are reduced.

In addition, it is a further object to improve the load response behavior of turbocharged internal combustion engines.

The object is achieved by a compressor assembly which comprises a spiral housing with a flow channel which is designed to convey a first fluid which can be sucked up from outside the compressor assembly. The compressor assembly furthermore comprises a compressor outlet flange which is fluidically connected to the spiral housing via the flow channel, and an injection device, wherein the injection device is designed to introduce a second fluid from outside the compressor assembly into the flow channel, wherein the injection device is arranged outside the flow channel of the spiral housing.

By means of the arrangement of the injection device outside the flow channel of the spiral housing, the following advantages arise: The second fluid injected by the injection device into the flow channel of the compressor assembly, and in particular in the flow channel of the diffuser of the compressor assembly, has a positive influence on the main flow in the flow channel, that is to say, the injected second fluid interacts with the first fluid of the main flow in the flow channel and supports or reinforces a swirl flow or spiral flow of the main flow. This advantageously leads to a reduction in pressure in the diffuser of the compressor assembly.

A further advantage consists in that a nozzle for injecting fluid into the flow channel of the compressor assembly can be realized without additional components. In addition, the injection device according to the invention, which can be realized with lower additional costs, does not impair the flow in the flow channel, which leads to greater efficiency during operation of the compressor assembly.

Embodiments Of The Invention

In one embodiment of the present invention, the injection device is at least partially incorporated in the spiral housing. The injection device comprises at least one opening to the flow channel so that fluid can be introduced from outside the compressor assembly into the flow channel by the injection device. In a preferred embodiment of the present invention, the injection device comprises a fluid channel.

In a preferred embodiment of the present invention, the injection device is attached to an outer wall of the spiral housing so that a fluid can be introduced from outside the compressor assembly via the injection device into the flow channel through an opening of the spiral housing.

In a preferred embodiment of the present invention, the outer wall of the spiral housing, to which outer wall the injection device is attached, forms part of an outer wall of the diffuser.

In a preferred embodiment of the present invention, the compressor outlet flange at least partially comprises an injection device so that fluid can be introduced from outside the compressor assembly into the flow channel of the spiral housing by the injection device.

In a preferred embodiment of the present invention, the injection device comprises a fluid channel in the compressor outlet flange, wherein the fluid channel comprises a first opening and a second opening, wherein a fluid can be introduced from outside the compressor assembly into the fluid channel via the first opening of the fluid channel, and wherein the second opening of the fluid channel fluidically connects the fluid channel to the flow channel of the spiral housing so that the introduced fluid can be introduced into the flow channel.

In a preferred embodiment of the present invention, a portion of the fluid channel is formed by a connection piece which is connectable to the compressor outlet flange.

In a preferred embodiment of the present invention, the injection device comprises a reservoir for storing the fluid and for the uniform distribution of the fluid over the circumference of the flow channel, wherein the reservoir comprises part of the fluid channel.

In a preferred embodiment of the present invention, the injection device comprises a connection element so that fluid can be introduced from outside the compressor assembly into the injection device via an injection element which is insertable into the connection element and is designed a as a nozzle.

In a preferred embodiment of the present invention, the injection device is of nozzle-shaped design.

In a preferred embodiment of the present invention, the compressor assembly comprises a diffuser, wherein the diffuser is fluidically connected to the spiral housing via the flow channel.

In a preferred embodiment of the present invention, the diffuser is designed as a conical diffuser.

In a preferred embodiment of the present invention, the diffuser is fluidically connected to the compressor outlet flange via the flow channel.

In a preferred embodiment of the present invention, a turbocharger comprises a compressor assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described below with reference to exemplary embodiments which are explained in more detail with reference to drawings, in which:

FIG. 1 shows a compressor assembly with an injection device in a sectional view according to a first embodiment of the present invention;

FIG. 2 shows a cutout of a compressor outlet flange with an integrated injection device according to a second embodiment of the present invention;

FIG. 3 shows a cutout of a compressor outlet flange with an injection device according to a third embodiment of the present invention;

FIG. 4 shows an exterior view of an exhaust gas turbocharger with a filter sound absorber, compressor outlet housing (spiral housing), a bearing housing, a gas outlet housing and a gas inlet housing.

In the description below, identical reference signs are used for parts which are identical and act in an identical manner.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 4 shows an exhaust gas turbocharger with an axial turbine and a radial compressor. The housing parts which can be seen in the exterior view are as follows, from left to right: the filter sound absorber 9 is located on the air inlet side of the compressor. The air sucked up via the filter sound absorber is guided through a central opening in the filter sound absorber into the adjacent compressor housing having the spiral housing 2. Indicated at the upper edge of the spiral housing is the compressor outlet flange 3 which is provided for the fastening of a pipe with which the compressed air is fed to an internal combustion engine. The compressor is driven via an exhaust gas turbocharger shaft which is mounted rotatably in the bearing housing 10. The shaft is driven by a turbine wheel which is arranged in the turbine housing. The turbine housing comprises a gas outlet housing 30 and a gas inlet housing 31 which, in the embodiment illustrated, is designed with two pipes.

FIG. 1 shows, in a section perpendicular to the shaft axis of the exhaust gas turbocharger through the spiral housing of a compressor assembly. The compressor assembly 1 comprises the spiral housing 2 with a flow channel 12, wherein the flow channel 12 is designed to convey a first fluid, such as, for example, air, which can be sucked up from outside the compressor assembly 1. The compressor assembly 1 furthermore comprises a compressor outlet flange 3 which is fluidically connected to the spiral housing 2 via the flow channel 12. The compressor assembly 1 furthermore comprises a diffuser 5. The diffuser 5 is fluidically connected to the compressor outlet flange 3 via the flow channel 12.

However, the diffuser 5 is also fluidically connected to the spiral housing 2 via the flow channel 12. The diffuser can also be designed here as a conical diffuser. The injection device 4 is designed to introduce a second fluid from outside the compressor assembly 1 into the flow channel 12. The injection device 4 is arranged outside the flow channel 12 of the spiral housing 2 in FIG. 1. The injection device 4 comprises a connection element 14 for the supply of a second fluid, and a fluid channel 13 through which the second fluid which can be introduced from outside the compressor assembly 1 flows. The fluid channel 13 is connected to the flow channel 12 via an opening 6 in the spiral housing. The second fluid which is injected via the fluid channel 13 therefore interacts with the first fluid in the flow channel 12 and can reinforce the swirl flow of the first fluid in the flow channel 12. In FIG. 1, the injection device 4 is partially incorporated into the spiral housing 2. In detail, the injection device 4 in FIG. 1 is attached to an outer wall 7 of the spiral housing 2 so that a second fluid can flow from outside the compressor assembly 1 via the injection device 4 into the flow channel 12 through the opening 6 in the spiral housing 2. In FIG. 1, the outer wall 7 of the spiral housing 2, to which outer wall the injection device 4 is attached, forms part of an outer wall 8 of the diffuser 5. The compressor assembly according to the embodiment of FIG. 1 can be part of a turbocharger (not illustrated).

FIG. 2 shows a cutout of a compressor outlet flange 11 with an injection device 13 integrated in the compressor outlet flange 11. Alternatively, the injection device 13 can also be incorporated only partially (not illustrated) into the compressor outlet flange 11 so that a second fluid can be introduced from outside the compressor assembly 1 into the flow channel 12 of the spiral housing 2 by the injection device 13. The injection device 13 comprises a fluid channel 23 in the compressor outlet flange 11, wherein the fluid channel 23 comprises a first opening 24 and a second opening 25, wherein a second fluid can be introduced from outside the compressor assembly 1 into the fluid channel 23 via the first opening 24 of the fluid channel 23, and wherein the second opening 25 of the fluid channel 23 fluidically connects the fluid channel 23 to the flow channel 12 of the spiral housing 2 so that the introduced second fluid can be introduced into the flow channel 12. In FIG. 2, the injection device 13 comprises a connection element 14. An injection element designed as a nozzle can be inserted into the injection device 4 in the connection element 14 so that the second fluid can be introduced from outside the compressor assembly 1 into the injection device 4. The injection device 13 can be of nozzle-shaped design here.

FIG. 3 shows a cutout of a compressor outlet flange 16 with an injection device 20 of a compressor assembly 1. The injection device 20 comprises a fluid channel 23 in the compressor outlet flange 17, wherein the fluid channel 23 comprises a first opening 24 and a second opening 25, wherein a second fluid can be introduced from outside the compressor assembly 1 into the fluid channel 23 via the first opening 24 of the fluid channel 23, and wherein the second opening 25 of the fluid channel 23 fluidically connects the fluid channel 23 to the flow channel 12 of the spiral housing 2 so that the introduced second fluid can be introduced into the flow channel 12. In contrast to FIG. 2, in the embodiment of FIG. 3, a portion of the fluid channel 23 is formed by a connection piece 18 which is connectable to the compressor outlet flange 16. This connection piece 18 can be configured here on the engine side. Also in FIG. 3, the injection device 20 comprises a connection element 14. Furthermore, the injection device 20 comprises a reservoir 19 for storing the second fluid and for the uniform distribution of the fluid over the circumference of the flow channel 12, wherein the reservoir 19 comprises part of the fluid channel 23. Also in the embodiment of FIG. 3, the injection device 20 can be of nozzle-shaped design.

In the embodiments of FIGS. 1 to 3, the injection device 4, 13, 20 can be arranged in each case in such a manner that the second fluid which can be introduced into the flow channel 12 by the injection device 4, 13, 20 optimally follows a swirl flow of the first fluid in the flow channel 12 of the compressor assembly 1 in order to reinforce the swirl flow of the first fluid.

In addition, in the embodiments of FIGS. 1 to 3, the fluid channel 13, 23 can form the contour for the nozzle.

LIST OF REFERENCE SIGNS

1 compressor assembly with diffuser

2 spiral housing of the compressor assembly (compressor outlet housing)

3 compressor outlet flange

4 injection device

5 diffuser

6 opening in the spiral housing

7 outer wall of the spiral housing

8 outer wall of the diffuser

9 filter sound absorber at the input of the compressor

10 bearing housing for the mounting of the shaft of the exhaust gas turbocharger

11 compressor outlet flange

12 flow channel

13 fluid channel of the injection device

14 connection element for supply of fluid

16 compressor outlet flange with connection piece

17 compressor outlet flange

18 connection piece

19 reservoir

20 injection device

23 fluid channel of the injection device

24 first opening of the injection device

25 second opening of the injection device

30 gas outlet housing of the turbine of the exhaust gas turbocharger

31 gas inlet housing of the turbine of the exhaust gas turbocharger

Claims

1. A turbocharger, comprising: a spiral housing (2) with a flow channel (12) which is designed to convey a first fluid which can be sucked up from outside the compressor assembly (1) and to feed said fluid to a compressor outlet; wherein the spiral housing comprises a diffuser,a compressor outlet flange (3, 11, 16) which is arranged on the spiral housing and is adjacent to the diffuser,an injection device (4, 13, 20) for improving the load response behavior of an internal combustion engine connected to the turbo charger, wherein the injection device (4, 13, 20) is designed to introduce a second fluid from outside the compressor assembly (1) into the flow channel (12) in the diffuser,wherein the injection device (4) is arranged outside the flow channel (12) of the spiral housing (2), whereinthe diffusor (5) is designed as a conical diffuser.

2. A compressor assembly (1) as claimed in claim 1, characterized in that the injection device (4) is at least partially incorporated in the spiral housing (2), and in that the injection device (4) comprises at least one opening (6) to the flow channel (12) so that the second fluid can be introduced from outside the compressor assembly (1) into the flow channel (12) by the injection device (4).

3. The compressor assembly (1) as claimed in claim 1, characterized in that the injection device (4) comprises a fluid channel (13).

4. The compressor assembly (1) as claimed in claim 1, characterized in that the injection device (4, 13, 20) is attached to an outer wall (7) of the spiral housing (2) so that a second fluid can be introduced from outside the compressor assembly (1) via the injection device (4) into the flow channel (12) through an opening (6) in the spiral housing (2).

5. The compressor assembly (1) as claimed in claim 4, characterized in that the outer wall (7) of the spiral housing (2), to which outer wall the injection device (4) is attached, forms part of an outer wall (8) of the diffuser (5).

6. The compressor assembly (1) as claimed in claim 1, characterized in that the compressor outlet flange (11) at least partially comprises an injection device (13) so that a second fluid can be introduced from outside the compressor assembly (1) by the injection device (13) into the flow channel (12) of the spiral housing (2).

7. The compressor assembly (1) as claimed in claim 6, characterized in that the injection device (20) comprises a fluid channel (23) in the compressor outlet flange (11), wherein the fluid channel (23) comprises a first opening (24) and a second opening (25), wherein a second fluid can be introduced from outside the compressor assembly (1) into the fluid channel (23) via the first opening (24) of the fluid channel (23), and wherein the second opening (25) of the fluid channel (23) fluidically connects the fluid channel (23) to the flow channel (12) of the spiral housing (2) so that the introduced second fluid can be introduced into the flow channel (12).

8. The compressor assembly (1) as claimed in claim 7, characterized in that a portion of the fluid channel (23) is formed by a connection piece (18) which is connectable to the compressor outlet flange (16).

9. The compressor assembly (1) as claimed in one of the preceding claims, characterized in that the injection device (4, 13, 20) has a reservoir (19) for storing the second fluid and for the uniform distribution of the second fluid over the circumference of the flow channel (12), wherein the reservoir (19) comprises part of the fluid channel (13, 23).

10. The compressor assembly (1) as claimed in one of the preceding claims, characterized in that the injection device (4, 13, 20) comprises a connection element (14) so that the second fluid can be introduced from outside the compressor assembly (1) into the injection device (4) via an injection element which is insertable into the connection element (14) and is designed a as a nozzle.

11. The compressor assembly (1) as claimed in one of the preceding claims, characterized in that the injection device (4, 13, 20) is of nozzle-shaped design.