WO2019123567A1

WO2019123567A1 - Turbine housing and turbocharger with said turbine housing

Info

Publication number: WO2019123567A1
Application number: PCT/JP2017/045707
Authority: WO
Inventors: 北村　剛; 東條　正希; 星　徹; 裕太石井
Original assignee: 三菱重工エンジン＆ターボチャージャ株式会社
Priority date: 2017-12-20
Filing date: 2017-12-20
Publication date: 2019-06-27

Abstract

This turbine housing has formed therein: a connection flow passage having an inlet opening at one end thereof; a scroll flow passage connecting to the other end of the connection flow passage; a diffuser flow passage having one end connecting to the scroll flow passage, and the other end having an outlet opening; and a WG flow passage which bypasses the scroll flow passage and which connects the connection flow passage and the diffuser flow passage. The WG flow passage includes a WG inlet opening which is open to the connection flow passage, and WG outlet opening which is open to the diffuser flow passage. The WG outlet opening has a first portion located inside the WG outlet opening or on the peripheral edge section of the WG outlet opening. When a first straight line is extended from the first portion toward the inlet opening in the direction perpendicular to the WG outlet opening, the first straight line passes through the inside of the inlet opening or the peripheral edge section of the inlet opening.

Description

Turbine housing and turbocharger provided with this turbine housing

The present disclosure relates to a turbine housing and a turbocharger provided with the turbine housing.

When the engine is started, it is necessary to raise the temperature of the catalyst early with the exhaust gas in order to activate the catalyst for purifying the exhaust gas. However, in a vehicle equipped with a turbocharger, when exhaust gas flows through the turbine of the turbocharger, a loss of thermal energy occurs in the turbine housing, the temperature of the exhaust gas decreases, and it takes time to activate the catalyst. There is a risk of For this reason, it is necessary to reduce the loss of thermal energy in the turbine housing.

The cause of loss of thermal energy in the turbine housing is that the connection flow path from the turbine housing to the scroll is relatively long and the connection flow path is often a curved pipe, and the waste gate flow path (WG flow path) It is considered that the bypass flow rate when the waste gate valve (WG valve) is opened decreases and the flow from the WG flow path interferes with the diffuser to warm up the turbine housing depending on the positional relationship with the connection flow path. Be For example, Patent Document 1 discloses a turbine housing having such a WG flow passage and a WG valve.

U.S. Pat. No. 8,904,785

However, there has been a problem that when the shape of the turbine housing is changed to reduce the loss of thermal energy in the turbine housing, turbine performance may be reduced during normal operation with the WG valve closed.

In view of the above, at least one embodiment of the present disclosure provides a turbine housing with reduced loss of thermal energy from exhaust gases while suppressing degradation of turbine performance, and a turbocharger including the turbine housing. The purpose is

(1) A turbine housing according to at least one embodiment of the present invention,
A connecting channel having an inlet opening at one end,
A scroll channel connected to the other end of the connection channel;
A diffuser channel having one end connected to the scroll channel and an outlet opening at the other end;
A turbine housing in which a waste gate flow path (WG flow path) is formed, which bypasses the scroll flow path and communicates the connection flow path with the diffuser flow path.
The WG channel is
Waste gate inlet opening (WG inlet opening) opened to the connection flow path;
Including a wastegate outlet opening (WG outlet opening) opening into the diffuser flow path,
The WG outlet opening is a first portion on the interior or periphery of the WG outlet opening, extending a first straight line from the first portion to the inlet opening perpendicularly to the WG outlet opening The first straight line has a first portion passing inside or on the periphery of the inlet opening.

According to the configuration of the above (1), when the WG flow passage bypasses the scroll flow passage, the exhaust gas easily flows in the WG flow passage due to the positional relationship between the WG outlet opening and the inlet opening of the connection flow passage. The flow rate of the exhaust gas flowing to the scroll flow path is suppressed, and the loss of thermal energy from the exhaust gas can be reduced in the turbine housing. In this configuration, only the positional relationship between the WG outlet opening and the inlet opening of the connection flow channel is limited, and no special configuration is provided in the path from the connection flow channel through the scroll flow channel to the diffuser flow channel. Therefore, it is possible to suppress a decrease in turbine performance during operation with the WG valve closed.

(2) In some embodiments, in the configuration of (1) above,
The connection flow passage is configured such that the flow passage area decreases from the inlet opening toward the scroll flow passage.

According to the configuration of (2), when the WG flow passage bypasses the scroll flow passage by the exhaust gas being less likely to flow through the connection flow passage from the inlet opening toward the scroll flow passage, the exhaust gas flows through the WG flow passage The flow rate of the exhaust gas flowing to the scroll flow path is suppressed, and the loss of thermal energy from the exhaust gas can be reduced in the turbine housing.

(3) In some embodiments, in the configuration of (2) above,
The area of the inlet opening is S1, and the channel area of the connection channel at the position closest to the scroll channel on the part where the WG inlet opening is formed is S, and the connection at the portion connected to the scroll channel Assuming that the flow passage area of the flow passage is A, S / S1 ≦ 1/2 and A <S.

According to the configuration of the above (3), the exhaust gas does not reliably flow in the connection flow channel from the inlet opening toward the scroll flow channel, so that the effects and advantages obtained by the configuration of the above (2) can be reliably obtained. .

(4) In some embodiments, in any of the configurations of (1) to (3) above,
The WG outlet opening is a second portion on the interior or periphery of the WG outlet opening, extending a second straight line from the second portion perpendicular to the WG outlet opening toward the outlet opening The second straight line has a second portion passing inside or on the periphery of the outlet opening.

According to the configuration of the above (4), the exhaust gas bypassing the scroll passage through the WG passage is likely to flow out of the diffuser passage, thereby further reducing the loss of heat energy from the exhaust gas in the turbine housing be able to.

(5) In some embodiments, in any of the configurations of (1) to (4) above,
A pipe formed of a sheet metal is connected to the turbine housing at least one of the inlet opening and the outlet opening.

In the configurations of (1) to (4) above, the layout when providing the turbine housing to the exhaust pipe may be limited. On the other hand, according to the configuration of the above (5), exhausting is achieved by connecting a thin walled plate made of sheet metal, ie, a pipe having a small heat capacity, to at least one of the inlet opening of the connecting channel and the outlet opening of the diffuser channel. The potential of the turbine housing layout can be extended while reducing the loss of thermal energy from the gas.

(6) A turbocharger according to at least one embodiment of the present invention,
The turbine housing according to any one of the above (1) to (5) is provided.

According to the configuration of the above (6), it is possible to reduce the loss of thermal energy from the exhaust gas while suppressing the deterioration of the turbine performance.

According to at least one embodiment of the present disclosure, the positional relationship between the WG outlet opening and the inlet opening of the connecting channel makes it easier for the exhaust gas to flow through the WG channel when the WG channel bypasses the scroll channel. Therefore, the flow rate of the exhaust gas flowing to the scroll passage is suppressed, and the loss of heat energy from the exhaust gas can be reduced in the turbine housing. In this configuration, only the positional relationship between the WG outlet opening and the inlet opening of the connection flow channel is limited, and no special configuration is provided in the path from the connection flow channel through the scroll flow channel to the diffuser flow channel. Therefore, it is possible to suppress a decrease in turbine performance during operation with the WG valve closed.

1 is a perspective view of a turbine housing according to Embodiment 1 of the present disclosure. It is a schematic diagram which shows the positional relationship of WG exit opening and the entrance opening of a connection flow path in the turbine housing which concerns on Embodiment 1 of this indication. FIG. 5 is a partial cross-sectional view of a turbine housing according to Embodiment 2 of the present disclosure. FIG. 7 is a schematic view showing a positional relationship between a WG outlet opening and an inlet opening of a connection channel and an outlet opening of a diffuser channel in a turbine housing according to a third embodiment of the present disclosure. FIG. 7 is a side view of a turbine housing according to Embodiment 4 of the present disclosure. 7 is a graph schematically showing the operation and effect of the turbine housing according to the first to fourth embodiments of the present disclosure.

Hereinafter, some embodiments of the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the following embodiments. The dimensions, materials, shapes, relative arrangements, and the like of components described in the following embodiments are not intended to limit the scope of the present invention, but merely illustrative examples.

(Embodiment 1)
As shown in FIG. 1, the turbine housing 1 of the turbocharger includes a connecting flow passage 2 including a connection flow passage 12, a scroll flow passage 3 including a scroll flow passage 13, and a diffuser flow including a diffuser flow passage 15. A waste gate passage (WG passage) 6 including a waste gate passage (WG passage) 16 for bypassing the scroll passage 13 and connecting the connection passage 12 and the diffuser passage 15 by bypassing the scroll passage 13 And have. That is, the turbocharger provided with the turbine housing 1 is a single scroll turbo.

One end of the connection channel 12 has an inlet opening 12 a, and the other end of the connection channel 12 is connected to the scroll channel 13. One end of the diffuser flow path 15 is connected to the scroll flow path 13 via the turbine flow path 4a, and the other end of the diffuser flow path 15 has an outlet opening 15a. The WG channel 16 includes a waste gate inlet opening (WG inlet opening) 16 a opening to the connection channel 12 and a waste gate outlet opening (WG outlet opening) 16 b opening to the diffuser channel 15.

The turbine housing 1 is provided with a turbine wheel 4 rotatable by the exhaust gas flowing through the scroll passage 13 and a waste gate valve (WG valve) 7 capable of opening and closing the outlet opening 16 b of the WG passage 16. .

As shown in FIG. 2, assume a first straight line 21 extending from the first portion 10, which is a portion on or inside the WG outlet opening 16b, perpendicular to the WG outlet opening 16b toward the inlet opening 12a. . The positional relationship between the WG outlet opening 16b and the inlet opening 12a is such that the first straight line 21 passes through a point A on the inside or the periphery of the inlet opening 12a. Preferably, the center C of the WG outlet opening 16b is circular, and the center C of the WG outlet opening 16b extends from the center of gravity of the shape to the inlet opening 12a perpendicular to the WG outlet opening 16b. Assuming a straight line 21 ', the first straight line 21' passes through a point A 'on the inside or the periphery of the inlet opening 12a.

Next, an operation of exhaust gas flowing in the turbine housing 1 according to the first embodiment will be described.
As shown in FIG. 1, when the WG valve 7 closes the WG outlet opening 16 b of the WG passage 16, the exhaust gas flowing into the connection passage 12 through the inlet opening 12 a is the WG passage 16. The whole quantity flows into the scroll flow path 13 without flowing through and flows through the scroll flow path 13. The exhaust gas flowing through the scroll passage 13 loses energy by working on the turbine wheel 4 and flows into the diffuser passage 15. The turbine wheel 4 is rotated by work by the exhaust gas. The exhaust gas flowing into the diffuser passage 15 flows out of the turbine housing 1 through the outlet opening 15a.

On the other hand, when the WG valve 7 opens the WG outlet opening 16b of the WG flow passage 16, a part of the exhaust gas flowing into the connection flow passage 12 flows through the WG flow passage 16 through the inlet opening 12a. As a result, the scroll flow passage 13 is bypassed to flow into the diffuser flow passage 15 and flow out of the turbine housing 1 through the outlet opening 15a. The remaining exhaust gas flows sequentially through the scroll flow passage 13 and the diffuser flow passage 15, and flows out of the turbine housing 1 through the outlet opening 15a.

In the first embodiment, when the WG passage 16 bypasses the scroll passage 13 due to the positional relationship between the WG outlet opening 16 b and the inlet opening 12 a as shown in FIG. It will be easier. As a result, the flow rate of the exhaust gas flowing to the scroll passage 13 is suppressed, so that the loss of thermal energy from the exhaust gas can be reduced in the turbine housing 1. In this configuration, only the positional relationship between the WG outlet opening 16 b and the inlet opening 12 a of the connection flow channel 12 is limited, and a special route is provided from the connection flow channel 12 through the scroll flow channel 13 to the diffuser flow channel 15. Since the above configuration is not provided, it is possible to suppress a decrease in turbine performance at the time of operation with the WG valve 7 closed. Also, by reducing the loss of thermal energy from the exhaust gas, the response of the turbocharger can also be improved.

Further, due to the positional relationship between the WG outlet opening 16b and the inlet opening 12a as shown in FIG. 2, the connecting flow passage portion 2 can be shaped so as not to have the curved pipe portion as much as possible, and as a result, the connecting flow The length of the passage 12 can be as short as possible. In this way, the residence time of the exhaust gas in the turbine housing 1 can be shortened, and the heat capacity of the turbine housing 1 can be reduced. Therefore, in the turbine housing 1, the loss of thermal energy from the exhaust gas is reduced. can do. Furthermore, when the length of the connection flow path 12 is made as short as possible, the obstruction of the flow of exhaust gas to the scroll flow path 13 is reduced, so turbine performance when the WG flow path 16 does not bypass the scroll flow path 13 It is possible to suppress the decrease.

Second Embodiment
Next, a turbine housing according to a second embodiment will be described. The turbine housing according to the second embodiment is different from the first embodiment in the shape of the connection flow passage 12. In the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description thereof is omitted.

As shown in FIG. 3, the connection flow passage 12 is configured such that the flow passage area decreases from the inlet opening 12 a toward the scroll flow passage 13. In this configuration, the area of the inlet opening is S1, the channel area of the connection channel 12 at the position 31 closest to the scroll channel 13 of the portion 30 where the WG inlet opening 16a is formed is S, and Assuming that the flow passage area of the connection flow passage 12 in the portion 32 connected to the scroll flow passage 13 is A, it is preferable that S / S1 ≦ 1/2 and A <S. The other configuration is the same as that of the first embodiment.

As in the first embodiment, when the WG flow passage 16 bypasses the scroll flow passage 13, a part of the exhaust gas flowing into the connection flow passage 12 through the inlet opening 12a passes through the WG flow passage 16 while the rest Exhaust gas flows into the scroll passage 13. In the second embodiment, the connection flow passage 12 is configured such that the flow passage area decreases from the inlet opening 12 a toward the scroll flow passage 13, so exhaust gas is connected from the inlet opening 12 a toward the scroll flow passage 13. Since it becomes difficult to flow through the flow passage 12, that is, the exhaust gas becomes easy to flow through the WG flow passage 16, the flow rate of the exhaust gas flowing into the scroll flow passage 13 is suppressed, and the turbine housing 1 loses heat energy from the exhaust gas Can be reduced.

The configuration of the connection flow channel 12 in which the flow channel area decreases from the inlet opening 12a toward the scroll flow channel 13 is S / S1 ≦ 1/2 and A <S as described above, the inlet opening 12a. Since it becomes difficult for exhaust gas to certainly flow through the connection channel 12 toward the scroll channel 13, the above-mentioned effect can be obtained reliably.

(Embodiment 3)
Next, a turbine housing according to the third embodiment will be described. The turbine housing according to the third embodiment further specifies the positional relationship between the WG outlet opening 16 b and the outlet opening 15 a of the diffuser channel 15 with respect to each of the first and second embodiments. The third embodiment will be described below in a form in which the positional relationship is further specified in the configuration of the first embodiment, but the positional relationship may be specified in the configuration of the second embodiment to be the third embodiment. In the third embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description thereof is omitted.

As shown in FIG. 4, assume a second straight line 22 extending from the second portion 11, which is a portion on the inside or the periphery of the WG outlet opening 16b, perpendicular to the WG outlet opening 16b toward the outlet opening 15a. . The positional relationship between the WG outlet opening 16b and the outlet opening 15a is such that the second straight line 22 passes through a point B on the inside or the periphery of the outlet opening 15a. Preferably, the center C of the WG outlet opening 16b is circular, and the center C of the WG outlet opening 16b extends from the center of gravity of the shape to the outlet opening 15a perpendicularly to the WG outlet opening 16b. Assuming a two straight line 22 ', the second straight line 22' passes through a point B 'on the inside or the periphery of the outlet opening 15a. The other configuration is the same as that of the first embodiment.

In the third embodiment, since the positional relationship between the WG outlet opening 16b and the inlet opening 12a is the same as that of the first embodiment, the WG channel 16 (see FIG. 1) bypasses the scroll channel 13 (see FIG. 1). In this case, the exhaust gas flowing into the connection flow passage 12 (see FIG. 1) through the inlet opening 12 a can easily flow in the WG flow passage 16. The exhaust gas flowing through the WG passage 16 and flowing into the diffuser passage 15 through the WG outlet opening 16b has a positional relationship between the WG outlet opening 16b and the outlet opening 15a as shown in FIG. , And easily flow out of the diffuser passage 15 through the outlet opening 15a. As a result, the residence time of the exhaust gas flowing through the WG passage 16 in the turbine housing 1 (see FIG. 1) is shortened, so that the loss of thermal energy from the exhaust gas can be further reduced in the turbine housing 1 .

Furthermore, in the third embodiment, preferably, the rotation axis L of the turbine wheel 4 passes through a point D on the inside or the periphery of the outlet opening 15a. With this configuration, the exhaust gas flowing in the scroll flow passage 13 without flowing in the WG flow passage 16 easily flows out of the diffuser flow passage 15 through the outlet opening 15 a. As a result, since the residence time of the exhaust gas flowing through the scroll flow passage 13 in the turbine housing 1 is shortened, the loss of thermal energy from the exhaust gas can be further reduced in the turbine housing 1.

(Embodiment 4)
Next, a turbine housing according to a fourth embodiment will be described. The turbine housing according to the fourth embodiment is such that each of the first to third embodiments has a pipe formed of a sheet metal. Although the fourth embodiment will be described below in the form in which the above-described piping is added to the configuration of the first embodiment, the above-described piping can be added to any of the configurations of the second and third embodiments to make the fourth embodiment. In the fourth embodiment, the same components as those of the first embodiment are designated by the same reference numerals, and the detailed description thereof is omitted.

As shown in FIG. 5,

pipes

41 and 42 formed of sheet metal are connected to the turbine housing 1 at each of the inlet opening 12 a and the outlet opening 15 a. The other configuration is the same as that of the first embodiment.

In the first to third embodiments, the positional relationship between the WG outlet opening 16b and the inlet opening 12a is limited, and in the third embodiment, the positional relationship between the WG outlet opening 16b and the outlet opening 15a is also limited. The layout when providing the turbine housing 1 to an exhaust pipe (not shown) may be limited. On the other hand, in the fourth embodiment, the

pipes

41 and 42 with thin wall thickness made of sheet metal, that is, small heat capacity, are connected to the turbine housing 1 at each of the inlet opening 12a and the outlet opening 15a. The possibility of the layout of the turbine housing 1 can be expanded while reducing the loss of energy.

In the fourth embodiment, the

pipes

41 and 42 are connected to each of the inlet opening 12a and the outlet opening 15a, but the

pipe

41 or 42 may be connected to any one of the inlet opening 12a and the outlet opening 15a.

In the fourth embodiment, a curved pipe may be provided depending on the layout when the turbine housing 1 is provided in the exhaust pipe (not shown) instead of the

straight pipes

41 and 42 as shown in FIG. 5. Further, by providing the heat insulating material so as to cover the outer peripheral surfaces of the

pipes

41 and 42, it is possible to further reduce the loss of thermal energy from the exhaust gas.

A turbocharger having a turbine housing 1 (of the present disclosure) according to Embodiments 1 to 4 is provided in an engine, and transition of the temperature (outlet temperature) of exhaust gas flowing out of the turbine housing 1 after engine startup is schematically shown in FIG. Show. FIG. 6 shows the transition of the temperature (outlet temperature) of the exhaust gas flowing out of the turbine housing as a comparative example different from the configuration of the first to fourth embodiments and the temperature (inlet temperature) of the exhaust gas flowing into each turbine housing ) Is also shown. The required value corresponds to the temperature required to activate the catalyst provided in the exhaust pipe.

In both the turbine housing 1 of the present disclosure and the turbine housing of the comparative example, the outlet temperature is lower than the inlet temperature because of the loss of thermal energy from the exhaust gas at them. However, in the turbine housing 1 of the present disclosure, the outlet temperature can reach the required value earlier than in the turbine housing of the comparative example, and therefore, catalyst activation can be performed early after engine startup.

DESCRIPTION OF SYMBOLS 1 turbine housing 2 connection flow path portion 3 scroll flow path portion 4 turbine wheel 4 a turbine flow path 5 diffuser flow path portion 6 waste gate flow path portion 7 waste gate valve 10 first portion 11 second portion 12 connection flow path 12 a inlet opening 13 scroll channel 15 diffuser channel 15a outlet opening 16 waste gate channel 16a waste gate inlet opening 16b waste gate outlet opening 21 first straight line 22 second straight line 30 WG inlet opening formed part 31 (of part 30) most Position 32 on the scroll flow channel side Part 41 where the connection flow channel and the scroll flow channel are connected Piping 42 Piping L Rotational axis

Claims

A connecting channel having an inlet opening at one end,
A scroll channel connected to the other end of the connection channel;
A diffuser channel having one end connected to the scroll channel and an outlet opening at the other end;
A turbine housing in which a waste gate flow path (WG flow path) is formed, which bypasses the scroll flow path and communicates the connection flow path with the diffuser flow path.
The WG channel is
Waste gate inlet opening (WG inlet opening) opened to the connection flow path;
Including a wastegate outlet opening (WG outlet opening) opening into the diffuser flow path,
The WG outlet opening is a first portion on the interior or periphery of the WG outlet opening, extending a first straight line from the first portion to the inlet opening perpendicularly to the WG outlet opening The turbine housing according to claim 1, wherein the first straight line passes through the inside or the periphery of the inlet opening.
The turbine housing according to claim 1, wherein the connection flow passage is configured to decrease a flow passage area from the inlet opening toward the scroll flow passage.
The area of the inlet opening is S1, and the channel area of the connection channel at the position closest to the scroll channel on the part where the WG inlet opening is formed is S, and the connection at the portion connected to the scroll channel The turbine housing according to claim 2, wherein S / S 1 ≦ 1/2 and A <S, where A is a flow passage area of the flow passage.
The WG outlet opening is a second portion on the interior or periphery of the WG outlet opening, extending a second straight line from the second portion perpendicular to the WG outlet opening toward the outlet opening The turbine housing according to any one of the preceding claims, wherein the second straight line has a second portion passing inside or on the peripheral edge of the outlet opening.
The turbine housing according to any one of claims 1 to 4, wherein a pipe formed of a sheet metal is connected to the turbine housing at least one of the inlet opening and the outlet opening.
A turbocharger comprising the turbine housing according to any one of claims 1 to 5.