JP6493333B2 - Supercharging system for internal combustion engines - Google Patents

Description

  The present invention relates to a supercharging system for an internal combustion engine having a high-pressure compressor disposed in an intake passage and a low-pressure compressor disposed upstream of the high-pressure compressor in the intake passage.

2. Description of the Related Art Conventionally, a supercharging system for an internal combustion engine having a high-pressure compressor disposed in an intake passage and a low-pressure compressor disposed upstream of the high-pressure compressor in the intake passage is known. An example of this type of internal combustion engine supercharging system is disclosed in Patent Document 1, for example.
In the supercharging system for an internal combustion engine described in Patent Document 1, a high-pressure compressor is provided in a high-pressure turbocharger having a high-pressure turbine, and a low-pressure compressor is provided in a low-pressure turbocharger having a low-pressure turbine. The high-pressure turbocharger is provided with a high-pressure compressor housing that houses a high-pressure compressor impeller (high-pressure compressor wheel) and a high-pressure turbine housing that houses a high-pressure turbine impeller (high-pressure turbine wheel). The low pressure turbocharger is provided with a low pressure compressor housing that houses a low pressure compressor impeller (low pressure compressor wheel) and a low pressure turbine housing that houses a low pressure turbine impeller (low pressure turbine wheel).
In the supercharging system for an internal combustion engine described in Patent Document 1, a high pressure compressor impeller and a high pressure turbine impeller are connected via a high pressure shaft, and a high pressure bearing that supports the high pressure shaft is accommodated in a high pressure bearing housing. ing. The low-pressure compressor impeller and the low-pressure turbine impeller are connected via a low-pressure shaft, and a low-pressure bearing that supports the low-pressure shaft is accommodated in the low-pressure bearing housing.

JP 2010-255534 A

  By the way, in the supercharging system for an internal combustion engine described in Patent Document 1, although a cooling water passage for cooling the high pressure bearing and the low pressure bearing is provided, heat for cooling or heating the high pressure compressor and the low pressure compressor is provided. There is no exchange medium passage. Therefore, in the supercharging system for an internal combustion engine described in Patent Document 1, the intake air supercharged by the high pressure compressor and the intake air supercharged by the low pressure compressor cannot be efficiently cooled or heated.

  In view of the above problems, an object of the present invention is to provide a supercharging system for an internal combustion engine that can efficiently cool or heat intake air that is supercharged by a high-pressure compressor and intake air that is supercharged by a low-pressure compressor. And

According to the present invention, an internal combustion engine body;
An intake passage connected to the internal combustion engine body;
A high-pressure compressor disposed in the intake passage;
A low-pressure compressor disposed upstream of the high-pressure compressor in the intake passage;
And the intake pressure compressor for heat exchange medium passage formed in the high-pressure compressor housing a part of which is formed of a passage therein, for the low-pressure compressor in which a part of the intake passage formed therein to the low pressure compressor housing formed A heat exchange medium passage having a heat exchange medium passage and a heat exchange medium temperature adjusting device for adjusting the temperature of the heat exchange medium;
The internal combustion engine, wherein the heat exchange medium circulates in the heat exchange medium circulation path in the order of the heat exchange medium temperature adjusting device, the low pressure compressor heat exchange medium path, and the high pressure compressor heat exchange medium path. A supercharging system is provided.

In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium may be a cooling medium.
In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium temperature adjusting device can also reduce the temperature of the cooling medium.

In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium may be a heating medium.
In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium temperature adjusting device can also increase the temperature of the heating medium.

In other words, in the supercharging system for an internal combustion engine of the present invention, the supercharging is performed by the intake air supercharged by the high pressure compressor disposed in the intake passage and the low pressure compressor disposed upstream of the high pressure compressor in the intake passage. In order to cool or heat the intake air, a high pressure compressor heat exchange medium passage formed in a high pressure compressor housing in which a part of the intake passage is formed, and a low pressure in which a part of the intake passage is formed A heat exchange medium circuit having a heat exchange medium passage for a low-pressure compressor formed in the compressor housing and a heat exchange medium temperature adjusting device for adjusting the temperature of the heat exchange medium is provided.
Further, in the earnest study of the present inventors, when the heat exchange medium circulates in the heat exchange medium circulation path in the order of the heat exchange medium temperature adjusting device, the heat exchange medium passage for the low pressure compressor, and the heat exchange medium passage for the high pressure compressor. The heat exchange medium is supercharged by the high pressure compressor rather than circulating through the heat exchange medium circulation path in the order of the heat exchange medium temperature adjusting device, the high pressure compressor heat exchange medium path, and the low pressure compressor heat exchange medium path. It has also been found that the intake air supercharged by the low-pressure compressor can be efficiently cooled or heated.
In view of this point, in the supercharging system for an internal combustion engine according to the present invention, the heat exchange medium is a heat exchange medium temperature adjusting device, a heat exchange medium passage for a low-pressure compressor, and a heat exchange medium passage for a high-pressure compressor in this order. Circulate.
Therefore, the supercharging system for an internal combustion engine of the present invention is more efficient than the supercharging system for an internal combustion engine described in Patent Document 1 in which a heat exchange medium passage for cooling or heating the high pressure compressor and the low pressure compressor is not provided. In particular, the intake air supercharged by the high pressure compressor and the intake air supercharged by the low pressure compressor can be cooled or heated.
Further, in the supercharging system for an internal combustion engine of the present invention, the heat exchange medium circulates in the heat exchange medium circulation path in the order of the heat exchange medium temperature adjusting device, the high pressure compressor heat exchange medium path, and the low pressure compressor heat exchange medium path. More efficiently, the intake air supercharged by the high pressure compressor and the intake air supercharged by the low pressure compressor can be cooled or heated.

In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium passage for the high-pressure compressor is located at a first position facing the high-pressure compressor impeller in the high-pressure compressor housing, or a position upstream of the first position. Are located in
The low-pressure compressor heat exchange medium passage may be arranged at a second position facing the low-pressure compressor impeller in the low-pressure compressor housing, or at a position upstream of the second position.

That is, in this supercharging system for an internal combustion engine, the heat exchange medium passage for the high-pressure compressor is disposed at the first position facing the high-pressure compressor impeller in the high-pressure compressor housing, or upstream from the first position. When the temperature of the heat exchange medium in the high-pressure compressor heat exchange medium passage is lower than the temperature of the intake air in the high-pressure compressor, the first position or the upstream side of the first position. In this position, the intake air in the high pressure compressor is cooled by the heat exchange medium in the heat exchange medium passage for the high pressure compressor. As a result, it is possible to suppress the possibility of deposits being deposited at the first position where deposits are likely to be deposited.
In other words, in this supercharging system for an internal combustion engine, the first heat exchange medium passage for the high-pressure compressor is disposed in the first position of the high-pressure compressor housing and the position upstream of the first position. The possibility of deposits depositing at one position can be suppressed.
Further, in this supercharging system for an internal combustion engine, the heat exchange medium passage for the low-pressure compressor is disposed at the second position facing the low-pressure compressor impeller in the low-pressure compressor housing, or upstream from the second position. When the temperature of the heat exchange medium in the heat exchange medium passage for the low-pressure compressor is lower than the temperature of the intake air in the low-pressure compressor, the second position or the upstream side of the second position. In this position, the intake air in the low-pressure compressor is cooled by the heat exchange medium in the heat exchange medium passage for the low-pressure compressor. As a result, it is possible to suppress the possibility of deposits being deposited at the second position where deposits are likely to be deposited.
In other words, in the supercharging system for an internal combustion engine, the first heat exchange medium passage for the low-pressure compressor is more than the case where the low-pressure compressor housing is not arranged at either the second position or the position upstream of the second position. The possibility that deposits are deposited at the two positions can be suppressed.

In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium circulation path may include another heat exchange medium temperature adjusting device that adjusts the temperature of the heat exchange medium.
Furthermore, in the supercharging system for an internal combustion engine of the present invention, the heat exchange medium is the heat exchange medium temperature adjustment device, the low pressure compressor heat exchange medium passage, the other heat exchange medium temperature adjustment device, or the high pressure compressor. The heat exchange medium circulation path may be circulated in the order of the heat exchange medium path.

That is, in this supercharging system for an internal combustion engine, the heat exchange medium is a heat exchange medium temperature adjustment device, a heat exchange medium passage for a low pressure compressor, another heat exchange medium temperature adjustment device for adjusting the temperature of the heat exchange medium, and a high pressure compressor. When the temperature of the heat exchange medium in the heat exchange medium circulation path is lower than the temperature of the intake air in the low-pressure compressor and the temperature of the intake air in the high-pressure compressor. The heat exchange medium that has been heated when it flows through the heat exchange medium passage for the low-pressure compressor is cooled when it flows through another heat exchange medium temperature adjusting device, and flows through the heat exchange medium passage for the high-pressure compressor.
In this supercharging system for an internal combustion engine, when the temperature of the heat exchange medium in the heat exchange medium circuit is higher than the temperature of the intake air in the low pressure compressor and the temperature of the intake air in the high pressure compressor, the heat for the low pressure compressor The heat exchange medium cooled when flowing through the exchange medium passage is heated when flowing through another heat exchange medium temperature adjusting device, and flows through the high-pressure compressor heat exchange medium passage.
Therefore, in the supercharging system for an internal combustion engine, the heat exchange medium that has flowed through the heat exchange medium passage for the low pressure compressor flows through the heat exchange medium passage for the high pressure compressor without flowing through the other heat exchange medium temperature control device. The intake air in the high-pressure compressor may not be sufficiently cooled when the intake air in the high-pressure compressor needs to be cooled, and the intake air in the high-pressure compressor cannot be sufficiently heated when the intake air in the high-pressure compressor needs to be heated The fear can be suppressed.
In the supercharging system for an internal combustion engine of the present invention, the heat exchange medium passage for the high-pressure compressor may be formed along a shroud surface that is a surface of a shroud portion facing the high-pressure compressor impeller in the high-pressure compressor housing. Good.
The heat exchange medium passage for the low-pressure compressor may be formed along a shroud surface that is a surface of a shroud portion facing the low-pressure compressor impeller in the low-pressure compressor housing.

  According to the present invention, the intake air supercharged by the high-pressure compressor and the intake air supercharged by the low-pressure compressor can be efficiently cooled or heated.

It is the figure which showed roughly the principal part of an example to which the supercharging system for internal combustion engines of 1st Embodiment was applied. FIG. 2 is a schematic enlarged cross-sectional view of a high-pressure compressor 4a of the high-pressure turbocharger 4 shown in FIG. FIG. 2 is a schematic enlarged cross-sectional view of a low-pressure compressor 5a of the low-pressure turbocharger 5 shown in FIG. It is a schematic block diagram of the other principal part of an example to which the supercharging system for internal combustion engines of 1st Embodiment was applied. It is a schematic block diagram of the other principal part of an example to which the supercharging system for internal combustion engines of 2nd Embodiment was applied. It is a schematic block diagram of the other principal part of an example to which the supercharging system for internal combustion engines of 3rd Embodiment was applied. The heat exchange medium in the heat exchange medium circuit 10 when the heat exchange medium is cooled by the heat exchange medium temperature adjusting device 10a in the example shown in FIG. 6 to which the supercharging system for an internal combustion engine of the third embodiment is applied. 4 and when the heat exchange medium is cooled by the heat exchange medium temperature adjusting device 10a in the example shown in FIG. 4 to which the internal combustion engine supercharging system of the first embodiment is applied. It is the figure which showed the temperature transition of the inside heat exchange medium. It is a schematic block diagram of the other principal part of an example to which the supercharging system for internal combustion engines of 4th Embodiment was applied.

Hereinafter, a first embodiment of a supercharging system for an internal combustion engine of the present invention will be described. FIG. 1 is a diagram schematically showing a main part of an example to which the supercharging system for an internal combustion engine of the first embodiment is applied. FIG. 2 is a schematic enlarged cross-sectional view of the high-pressure compressor 4a of the high-pressure turbocharger 4 shown in FIG. FIG. 3 is a schematic enlarged cross-sectional view of the low-pressure compressor 5a of the low-pressure turbocharger 5 shown in FIG. FIG. 4 is a schematic block diagram of another main part of an example to which the supercharging system for an internal combustion engine of the first embodiment is applied.
In the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, an intake passage 2 (see FIGS. 1, 2 and 3) and an exhaust passage 3 (see FIG. 1). Are connected to the internal combustion engine body 1 (see FIG. 1). A high-pressure compressor 4a (see FIGS. 1 and 2) that is a compressor of the high-pressure turbocharger 4 (see FIGS. 1 and 2) is disposed in the intake passage 2. A high-pressure compressor heat exchange medium passage 4a1f (see FIGS. 2 and 4) is formed in a high-pressure compressor housing 4a1 (see FIGS. 2 and 4) that is a housing of the high-pressure compressor 4a.
The high-pressure compressor housing 4a1 houses a high-pressure compressor impeller 4a2 (see FIGS. 1 and 2). The high-pressure compressor impeller 4a2 is connected to a high-pressure turbine impeller 4c2 (see FIG. 1) of the high-pressure turbine 4c (see FIG. 1) through a shaft 4b (see FIGS. 1 and 2). The shaft 4b is supported by a bearing (not shown) so as to be rotatable around a central axis 4b1 (see FIG. 2). The high-pressure compressor housing 4a1 is provided with an inlet passage 4a1a (see FIG. 2) extending in the direction of the central axis 4b1 of the shaft 4b and a scroll passage 4a1b (see FIG. 2) extending in the circumferential direction of the shaft 4b. ing. The inlet passage 4a1a is connected to a portion of the intake passage 2 upstream of the high-pressure compressor 4a. The scroll passage 4a1b is connected to a portion of the intake passage 2 on the downstream side of the high-pressure compressor 4a.
In the example shown in FIG. 2 to which the supercharging system for an internal combustion engine of the first embodiment is applied, the shroud surface 4a1d, which is the surface of the shroud portion 4a1c, is raised from the inlet passage 4a1a toward the central axis 4b1. It faces the high-pressure compressor impeller 4a2. A diffuser portion 4a1e is provided between the high-pressure compressor impeller 4a2 and the scroll passage 4a1b. The kinetic energy of the intake air sent out by the high-pressure compressor impeller 4a2 is converted into pressure by the diffuser portion 4a1e, whereby the intake air is compressed and the intake air temperature rises.

  In the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, the intake air before the temperature rises due to compression by the high-pressure compressor 4a (see FIGS. 1 and 2) is taken as the intake air. Cooling by the heat exchange medium in the heat exchange medium passage 4a1f (see FIGS. 2 and 4) for the high-pressure compressor at a lower temperature, or by the heat exchange medium in the heat exchange medium passage 4a1f for the high-pressure compressor having a temperature higher than that of the intake air A position where the heat exchange medium passage 4a1f for the high-pressure compressor faces the high-pressure compressor impeller 4a2 (see FIGS. 1 and 2) in the high-pressure compressor housing 4a1 (see FIGS. 2 and 4) so that it can be heated ( (Corresponding to “first position” of claim 4).

In the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, the high-pressure compressor 4a (see FIGS. 1 and 2) in the intake passage 2 (see FIGS. 1, 2, and 3). A low-pressure compressor 5a (see FIGS. 1 and 3), which is a compressor of the low-pressure turbocharger 5 (see FIGS. 1 and 3), is disposed upstream of the upstream side (see FIG. 2). A low-pressure compressor heat exchange medium passage 5a1f (see FIGS. 3 and 4) is formed in a low-pressure compressor housing 5a1 (see FIGS. 3 and 4) that is a housing of the low-pressure compressor 5a.
The low-pressure compressor housing 5a1 houses a low-pressure compressor impeller 5a2 (see FIGS. 1 and 3). The low-pressure compressor impeller 5a2 is connected to the low-pressure turbine impeller 5c2 (see FIG. 1) of the low-pressure turbine 5c (see FIG. 1) through a shaft 5b (see FIGS. 1 and 3). The shaft 5b is supported by a bearing (not shown) so as to be rotatable around a central axis 5b1 (see FIG. 3). The low-pressure compressor housing 5a1 is provided with an inlet passage 5a1a (see FIG. 3) extending in the direction of the central axis 5b1 of the shaft 5b and a scroll passage 5a1b (see FIG. 3) extending in the circumferential direction of the shaft 5b. ing. The inlet passage 5a1a is connected to a portion of the intake passage 2 upstream of the low-pressure compressor 5a. The scroll passage 5a1b is connected to a portion of the intake passage 2 on the downstream side of the low-pressure compressor 5a.
In the example shown in FIG. 3 to which the supercharging system for an internal combustion engine of the first embodiment is applied, the shroud surface 5a1d, which is the surface of the shroud portion 5a1c, is raised from the inlet passage 5a1a toward the central axis 5b1. It faces the low-pressure compressor impeller 5a2. A diffuser portion 5a1e is provided between the low-pressure compressor impeller 5a2 and the scroll passage 5a1b. The kinetic energy of the intake air sent out by the low-pressure compressor impeller 5a2 is converted into pressure by the diffuser portion 5a1e, whereby the intake air is compressed and the temperature of the intake air rises. Blow-by gas containing oil or the like is introduced from the internal combustion engine body 1 (see FIG. 1) into a portion of the intake passage 2 upstream of the low-pressure compressor 5a through a blow-by gas passage (not shown).

  In the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, the intake air before the temperature rises by being compressed by the low-pressure compressor 5a (see FIGS. 1 and 3) is taken as the intake air. Cooling by the heat exchange medium in the heat exchange medium passage 5a1f (see FIGS. 3 and 4) for the low-pressure compressor at a lower temperature, or by the heat exchange medium in the heat exchange medium passage 5a1f for the low-pressure compressor having a temperature higher than that of the intake air A position where the heat exchange medium passage 5a1f for the low-pressure compressor faces the low-pressure compressor impeller 5a2 (see FIGS. 1 and 3) in the low-pressure compressor housing 5a1 (see FIGS. 3 and 4) so that it can be heated ( (Corresponding to “second position” of claim 5).

  In the example shown in FIG. 1 to which the internal combustion engine supercharging system of the first embodiment is applied, an intake bypass passage 6a that bypasses the high-pressure compressor 4a of the high-pressure turbocharger 4, and an intake bypass disposed in the intake bypass passage 6a. A valve 6b is provided. An exhaust bypass passage 7a that bypasses the high-pressure turbine 4c of the high-pressure turbocharger 4 and an exhaust bypass valve 7b disposed in the exhaust bypass passage 7a are provided. Furthermore, a waste gate passage 8a that bypasses the low pressure turbine 5c of the low pressure turbocharger 5 and a waste gate valve 8b disposed in the waste gate passage 8a are provided. A signal for controlling the intake bypass valve 6b, a signal for controlling the exhaust bypass valve 7b, and a signal for controlling the waste gate valve 8b are output from an ECU (electronic control unit) 50.

In the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, the high pressure compressor heat exchange medium passage 4a1f formed in the high pressure compressor housing 4a1 (see FIGS. 2 and 4). (See FIGS. 2 and 4), the low-pressure compressor heat exchange medium passage 5a1f (see FIGS. 3 and 4) formed in the low-pressure compressor housing 5a1 (see FIGS. 3 and 4), and the temperature of the heat exchange medium. A heat exchange medium circulation path 10 (see FIG. 4) having a heat exchange medium temperature adjusting device 10a (see FIG. 4) to be adjusted and a pump 10b (see FIG. 4) is provided.
In detail, in the example shown in FIG. 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, the heat exchange medium temperature adjusting device 10a and the pump 10b are connected via the heat exchange medium passage 10c1, The pump 10b and the low-pressure compressor heat exchange medium passage 5a1f of the low-pressure compressor housing 5a1 are connected via the heat exchange medium passage 10c2, and the low-pressure compressor heat exchange medium passage 5a1f and the high-pressure compressor heat exchange medium passage of the high-pressure compressor housing 4a1. 4a1f is connected via a heat exchange medium passage 10c3, and the high pressure compressor heat exchange medium passage 4a1f and the heat exchange medium temperature adjusting device 10a are connected via a heat exchange medium passage 10c4.
In the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, for example, because the outside air temperature is higher than a preset threshold, the high pressure compressor 4a (FIGS. 1 and 2), when the intake air supercharged by the low pressure compressor 5a (see FIGS. 1 and 3) needs to be cooled, the heat exchange medium temperature adjusting device 10a causes the temperature of the heat exchange medium to be cooled. Can be lowered. That is, the heat exchange medium in the high-pressure compressor heat exchange medium passage 4a1f and the heat exchange medium in the low-pressure compressor heat exchange medium passage 5a1f function as a cooling medium.
Furthermore, in the example shown in FIGS. 1 to 4 to which the supercharging system for the internal combustion engine of the first embodiment is applied, for example, since the outside air temperature is lower than a preset threshold value, supercharging is performed by the high pressure compressor 4a. When it is necessary to heat the intake air and the intake air supercharged by the low-pressure compressor 5a, the temperature of the heat exchange medium is raised by the heat exchange medium temperature adjusting device 10a. That is, the heat exchange medium in the high-pressure compressor heat exchange medium passage 4a1f and the heat exchange medium in the low-pressure compressor heat exchange medium passage 5a1f function as the heating medium.
Therefore, in the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, a heat exchange medium passage for cooling or heating the high pressure compressor 4a and the low pressure compressor 5a is provided. The intake air supercharged by the high-pressure compressor 4a and the intake air supercharged by the low-pressure compressor 5a can be cooled or heated more efficiently than the supercharging system for an internal combustion engine described in Japanese Patent Application Laid-Open No. 2003-260260.

  Furthermore, in earnest research of the inventor, as shown by a solid arrow “first embodiment” in FIG. 4, the heat exchange medium is a heat exchange medium temperature adjustment device 10 a, a heat exchange medium passage 5 a 1 f for a low pressure compressor, a high pressure When the heat exchange medium circulation path 10 is circulated in the order of the heat exchange medium passage 4a1f for the compressor, the heat exchange medium is converted into the heat exchange medium temperature adjusting device 10a, The intake air supercharged by the high pressure compressor 4a (see FIGS. 1 and 2) and the heat exchange medium passage 10a in order of the heat exchange medium passage 4a1f for the high pressure compressor and the heat exchange medium passage 5a1f for the low pressure compressor in this order. It has been found that the intake air supercharged by the low-pressure compressor 5a (see FIGS. 1 and 3) can be efficiently cooled or heated.

  Specifically, in the earnest study of the present inventor, heat exchange medium in the high-pressure compressor housing 4a1 (see FIGS. 2 and 4) and the low-pressure compressor housing 5a1 (see FIGS. 3 and 4) is a first precondition. Is set to 10 [%], the intake air temperature Tgin [° C.] entering each of the high pressure compressor housing 4a1 and the low pressure compressor housing 5a1, and the high pressure compressor housing 4a1 and the low pressure compressor housing 5a1 respectively. Based on the temperature Twin [° C.] of the heat exchange medium and the following Equation 1, the temperature Tgout [° C.] of the intake air that exits from each of the high-pressure compressor housing 4a1 and the low-pressure compressor housing 5a1 was calculated. In the earnest study of the present inventors, water was used as a heat exchange medium.

Further, in the earnest study of the present inventor, the second precondition is that the intake air temperature decreases in the high pressure compressor housing 4a1 (see FIGS. 2 and 4) and the low pressure compressor housing 5a1 (see FIGS. 3 and 4). It was assumed that all the heat was taken away by the heat exchange medium. Further, as a third precondition, the temperature of the heat exchange medium after being lowered by the heat exchange medium temperature adjusting device 10a (see FIG. 4) is set to 50 [° C.], and the high pressure compressor housing 4a1 and the low pressure compressor housing The flow rate of the heat exchange medium entering each of 5a1 was set to 2 [L / min]. Further, as a fourth precondition, the compressor efficiency ηcomp in each of the high-pressure compressor 4a (see FIGS. 1 and 2) and the low-pressure compressor 5a (see FIGS. 1 and 3) is set to 70 [%]. As a precondition, it was assumed that the intake air was air.
Specifically, the intake air temperature Tgin [° C.] entering each of the high-pressure compressor housing 4a1 and the low-pressure compressor housing 5a1, the intake air temperature Tgout [° C.] exiting from each of the high-pressure compressor housing 4a1 and the low-pressure compressor housing 5a1, and the high pressure The high-pressure compressor housing 4a1 and the low-pressure compressor are based on the absolute pressure Pin [kPa] of the intake air entering each of the compressor housing 4a1 and the low-pressure compressor housing 5a1, the compressor efficiency ηcomp, the specific heat ratio κ of the intake air, and the following equation 2. The absolute pressure Pout [kPa] of the intake air discharged from each of the housings 5a1 was calculated.

In addition, in the earnest study of the present inventor, the sixth precondition is that the flow rate of intake air entering each of the high-pressure compressor housing 4a1 (see FIGS. 2 and 4) and the low-pressure compressor housing 5a1 (see FIGS. 3 and 4) is It was set to 70 [g / s].
Furthermore, in the diligent research of the present inventor, as a seventh precondition, the intake air supercharged by the high pressure compressor 4a (see FIGS. 1 and 2) and the supercharged by the low pressure compressor 5a (see FIGS. 1 and 3) are used. When the intake air is not cooled by the heat exchange medium, the absolute pressure of the intake air at the position P1a (see FIG. 1) upstream of the low-pressure compressor 5a in the intake passage 2 (see FIG. 1) is set to 100 [kPa]. The temperature of the intake air at the position P1a is set to 25 [° C.]. Further, based on the above formula 2 or the like, the absolute value 150 kPa of the intake air pressure at the position P1b (see FIG. 1) between the low pressure compressor 5a and the high pressure compressor 4a in the intake passage 2 is calculated. A value 80 [° C.] of the temperature of the intake air at the position P1b was calculated. Further, based on the above formula 2 and the like, the absolute pressure value 270 [kPa] of the intake air at the position P1c (see FIG. 1) downstream of the high-pressure compressor 4a in the intake passage 2 is calculated, and the intake air at the position P1c is calculated. A temperature value of 170 [° C.] was calculated.
Further, in the diligent research of the present inventors, as an eighth precondition, it is assumed that the pressure ratio of the high-pressure compressor 4a is always constant, and the pressure ratio of the low-pressure compressor 5a is always constant.

In earnest research of the inventor, as shown by a solid line arrow “first embodiment” in FIG. 4, the heat exchange medium is a heat exchange medium temperature adjusting device 10 a, a heat exchange medium passage 5 a 1 f for a low pressure compressor, a high pressure compressor. When the heat exchange medium circulation path 10 is circulated in the order of the heat exchange medium passages 4a1f, the heat exchange at the position P2a (see FIG. 4) on the upstream side of the heat exchange medium passages 5a1f for the low-pressure compressor according to the third precondition. The temperature of the medium becomes 50 [° C.], and the temperature of the intake air at the position P1a (see FIG. 1) becomes 25 [° C.] according to the seventh precondition, and the first to eighth preconditions and the above The temperature of the intake air at the position P1b (see FIG. 1) is 77 [° C.] by the calculation of the expressions 1 and 2.
That is, in the earnest research of the inventor, the temperature of the intake air at position P1b (77 [° C.]) in the example shown by the solid arrow “first embodiment” in FIG. 4 is not cooled by the heat exchange medium. Compared to the temperature of the intake air at position P1b (80 [° C.]), the temperature decreased by 3 [° C.]. According to the above first to eighth preconditions, a decrease of 3 [° C.] in the intake air temperature corresponds to an increase in [° C.] of 1.5 in the temperature of the heat exchange medium. As a result, the temperature of the heat exchange medium at the position P2b (see FIG. 4) between the heat exchange medium passage 5a1f for the low pressure compressor and the heat exchange medium passage 4a1f for the high pressure compressor was 51.5 [° C.].
Furthermore, in earnest research by the present inventor, the position P1c (FIG. 1) is obtained by calculating the intake air temperature (77 [° C.]) at the position P1b, the first to eighth preconditions, and the calculations of the expressions 1 and 2. The temperature of the intake air in the reference) became 156.8 [° C.]. Further, the temperature of the heat exchange medium at the position P2c (see FIG. 4) on the downstream side of the high-pressure compressor heat exchange medium passage 4a1f was 58.2 [° C.].

In addition, in earnest research by the present inventor, as shown by a one-dot chain line arrow “Comparative Example” in FIG. 4, the heat exchange medium is a heat exchange medium temperature adjusting device 10 a, a heat exchange medium passage 4 a 1 f for high pressure compressor, a low pressure compressor. When the heat exchange medium circulation path 10 is circulated in the order of the heat exchange medium passages 5a1f, the heat exchange at the position P2c (see FIG. 4) on the upstream side of the high pressure compressor heat exchange medium path 4a1f is performed according to the third precondition. The temperature of the medium becomes 50 [° C.], and the temperature of the intake air at the position P1a (see FIG. 1) becomes 25 [° C.] according to the seventh precondition, and the first to eighth preconditions and the above The temperature of the intake air at the position P1b (see FIG. 1) became 78 [° C.] by the calculations of the expressions 1 and 2.
Further, in earnest research by the present inventor, the position P1c (FIG. 1) is obtained by calculating the intake air temperature (78 [° C.]) at the position P1b, the first to eighth preconditions, and the calculations of the above formulas 1 and 2. The temperature of the intake air in the reference) became 157.8 [° C.].
That is, in earnest research of the inventor, the temperature of the intake air (157.8 [° C.]) at the position P1c in the example indicated by the one-dot chain line arrow “Comparative Example” in FIG. 4 is not cooled by the heat exchange medium. Compared with the temperature of the intake air at position P1c (170 [° C.]) at about 12 [° C.]. According to the above first to eighth preconditions, a decrease of about 12 [° C.] in the intake air temperature corresponds to an increase in [° C.] of 10.1 in the temperature of the heat exchange medium. As a result, the temperature of the heat exchange medium at the position P2b (see FIG. 4) between the heat exchange medium passage 5a1f for the low pressure compressor and the heat exchange medium passage 4a1f for the high pressure compressor was 60.1 [° C.]. Further, the temperature of the heat exchange medium at the position P2a (see FIG. 4) on the downstream side of the heat exchange medium passage 5a1f for the low-pressure compressor was 61.1 [° C.].

As described above, in earnest research of the present inventors, as shown by the solid line arrow “first embodiment” in FIG. 4, the heat exchange medium is the heat exchange medium temperature adjusting device 10 a, the heat exchange medium passage for the low-pressure compressor. When the heat exchange medium circulation path 10 is circulated in the order of 5a1f and the high-pressure compressor heat exchange medium path 4a1f, the heat exchange medium is adjusted as shown in FIG. It is supercharged by the high-pressure compressor 4a (see FIGS. 1 and 2) rather than circulating through the heat exchange medium circulation path 10 in the order of the apparatus 10a, the high-pressure compressor heat exchange medium path 4a1f, and the low-pressure compressor heat exchange medium path 5a1f. It has been found that the intake air supercharged by the intake air and the low pressure compressor 5a (see FIGS. 1 and 3) can be efficiently cooled.
Similarly, in the earnest study of the inventor, as shown by a solid arrow “first embodiment” in FIG. 4, the heat exchange medium is a heat exchange medium temperature adjusting device 10 a, a heat exchange medium passage 5 a 1 f for a low-pressure compressor, When the heat exchange medium circulation path 10 is circulated in the order of the heat exchange medium passages 4a1f for the high-pressure compressor, the heat exchange medium is converted into the heat exchange medium temperature adjusting device 10a as shown by a one-dot chain arrow “comparative example” in FIG. The high-pressure compressor heat exchange medium passage 4a1f and the low-pressure compressor heat exchange medium passage 5a1f are supercharged by the intake air and the low-pressure compressor 5a that are supercharged by the high-pressure compressor 4a rather than circulating through the heat exchange medium circulation passage 10 in this order. It was found that the intake air can be heated efficiently.
In view of this point, in the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, as shown by a solid arrow “first embodiment” in FIG. The medium circulates through the heat exchange medium circulation path 10 in the order of the heat exchange medium temperature adjusting device 10a, the low pressure compressor heat exchange medium passage 5a1f, and the high pressure compressor heat exchange medium passage 4a1f.
Therefore, in the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, the heat exchange medium is a heat exchanger as shown by a one-dot chain line arrow “Comparative Example” in FIG. Intake air that is supercharged by the high-pressure compressor 4a more efficiently than the case where the medium temperature adjusting device 10a, the heat exchange medium passage 4a1f for the high-pressure compressor, and the heat exchange medium passage 5a1f for the low-pressure compressor are circulated in this order. And the intake air supercharged by the low-pressure compressor 5a can be cooled or heated.
Specifically, in the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, intake air supercharged by the high pressure compressor 4a and intake air supercharged by the low pressure compressor 5a are used. By efficiently cooling, the volumetric efficiency can be improved, and thereby the torque can be improved.

Further, as described above, in the example shown in FIG. 2 to which the internal combustion engine supercharging system of the first embodiment is applied, the high-pressure compressor heat exchange medium passage 4a1f is a high-pressure compressor impeller in the high-pressure compressor housing 4a1. In another example in which the supercharging system for an internal combustion engine according to the first embodiment is applied, the high-pressure compressor heat exchange medium passage 4a1f is disposed in a position opposite to 4a2, and the high-pressure compressor impeller in the high-pressure compressor housing 4a1 is used. It is arrange | positioned in the position of the upstream (left side of FIG. 2) rather than the position which opposes 4a2.
Therefore, in the supercharging system for an internal combustion engine of the first embodiment, when the temperature of the heat exchange medium in the high-pressure compressor heat exchange medium passage 4a1f is lower than the temperature of the intake air in the high-pressure compressor 4a, the high-pressure compressor impeller 4a2 The intake air in the high-pressure compressor 4a is cooled by the heat exchange medium in the heat exchange medium passage 4a1f for the high-pressure compressor at a position opposite to the position or a position upstream of the position (left side in FIG. 2). As a result, it is possible to suppress the possibility of deposits being deposited at positions facing the high-pressure compressor impeller 4a2 where deposits are easily deposited.
That is, in the supercharging system for an internal combustion engine of the first embodiment, any of the position where the heat exchange medium passage 4a1f for the high-pressure compressor faces the high-pressure compressor impeller 4a2 and the position on the upstream side (the left side in FIG. 2) from that position. The possibility of deposits depositing at a position facing the high-pressure compressor impeller 4a2 can be suppressed as compared with the case where the deposit is not arranged.

Furthermore, as described above, in the example shown in FIG. 3 to which the supercharging system for the internal combustion engine of the first embodiment is applied, the low-pressure compressor heat exchange medium passage 5a1f is a low-pressure compressor impeller in the low-pressure compressor housing 5a1. In another example in which the supercharging system for an internal combustion engine of the first embodiment is applied to a position opposed to 5a2, the low-pressure compressor heat exchange medium passage 5a1f is a low-pressure compressor impeller in the low-pressure compressor housing 5a1. It is arrange | positioned in the position of the upstream (left side of FIG. 3) rather than the position which opposes 5a2.
Therefore, in the supercharging system for an internal combustion engine of the first embodiment, when the temperature of the heat exchange medium in the heat exchange medium passage 5a1f for the low pressure compressor is lower than the temperature of the intake air in the low pressure compressor 5a, the low pressure compressor impeller 5a2 The intake air in the low-pressure compressor 5a is cooled by the heat exchange medium in the heat exchange medium passage 5a1f for the low-pressure compressor at a position opposite to the position or a position upstream of the position (left side in FIG. 3). As a result, it is possible to suppress the possibility of deposits being deposited at positions facing the low-pressure compressor impeller 5a2 where deposits are easily deposited.
That is, in the supercharging system for the internal combustion engine of the first embodiment, any of the position where the heat exchange medium passage 5a1f for the low pressure compressor faces the low pressure compressor impeller 5a2 and the position upstream (left side in FIG. 3) from that position. The possibility of deposits depositing at a position facing the low-pressure compressor impeller 5a2 can be suppressed as compared with the case where the deposit is not arranged.

In the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, the heat exchange medium circulation path 10 (see FIG. 4) cools the internal combustion engine body 1 (see FIG. 1). It is provided separately from an engine coolant circulation path (not shown).
Specifically, in the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system according to the first embodiment is applied, the engine cooling water radiator (see FIG. 4) is used as the heat exchange medium temperature adjusting device 10a (see FIG. 4). (Not shown) is used, for example, a radiator provided separately from the engine coolant radiator is used. The radiator used as the heat exchange medium temperature adjusting device 10a is configured in the same manner as a known engine coolant radiator, for example.
That is, in the example shown in FIGS. 1 to 4 to which the internal combustion engine supercharging system of the first embodiment is applied, the heat exchange medium temperature adjusting device 10a that functions in the same manner as a known engine coolant radiator performs heat generation. The temperature of the heat exchange medium circulating in the exchange medium circuit 10 is lowered.
Furthermore, in the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, in order to increase the temperature of the heat exchange medium circulating in the heat exchange medium circulation path 10, for example, A heater (not shown) configured in the same manner as a known electric heater is provided in the heat exchange medium temperature adjusting device 10a.
In another example to which the supercharging system for an internal combustion engine of the first embodiment is applied, the heat of the exhaust gas of the internal combustion engine described in, for example, Japanese Patent No. 5772652 is recovered and used instead of the heater. Any known device such as an exhaust heat recovery device is provided in the heat exchange medium temperature adjusting device 10a, and the device can raise the temperature of the heat exchange medium circulating in the heat exchange medium circulation path 10. it can.
As described above, in the example shown in FIGS. 1 to 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, the heat exchange medium temperature adjusting device 10a is heated to circulate through the heat exchange medium circulation path 10. Although it has a function of lowering the temperature of the exchange medium and a function of raising the temperature of the heat exchange medium circulating in the heat exchange medium circuit 10, the supercharging system for an internal combustion engine of the first embodiment is applied. In another example, the heat exchange medium temperature adjusting device 10a may have only a function of reducing the temperature of the heat exchange medium circulating in the heat exchange medium circulation path 10.
Alternatively, in still another example to which the internal combustion engine supercharging system according to the first embodiment is applied, the heat exchange medium temperature adjustment device 10 a increases the temperature of the heat exchange medium circulating in the heat exchange medium circulation path 10. It can also have only functions.

In the example shown in FIGS. 1 to 4 to which the supercharging system for the internal combustion engine of the first embodiment is applied, the high pressure compressor 4a and the low pressure compressor 5a are arranged in series in the intake passage 2 as shown in FIG. 4, as indicated by a solid arrow “first embodiment”, the heat exchange medium is in the order of the heat exchange medium temperature adjusting device 10a, the low pressure compressor heat exchange medium passage 5a1f, and the high pressure compressor heat exchange medium passage 4a1f. In another example to which the supercharging system for the internal combustion engine of the first embodiment is applied, the heat exchange medium circulation path 10 is circulated instead of the low-pressure compressor 5a in the intake passage 2 to the upstream side. One or more other compressors (not shown) can be added and arranged.
In another example to which the supercharging system for an internal combustion engine according to the first embodiment is applied, the heat exchange medium is a heat exchange medium temperature adjusting device 10a, the heat exchange medium passage for one or more other compressors described above ( The low-pressure compressor heat exchange medium passage 5a1f and the high-pressure compressor heat exchange medium passage 4a1f are circulated through the heat exchange medium circulation path 10 in this order.

  In the example shown in FIGS. 1 to 4, the supercharging system for the internal combustion engine of the first embodiment is compared with the supercharging system for the internal combustion engine having the high pressure compressor 4 a of the high pressure turbocharger 4 and the low pressure compressor 5 a of the low pressure turbocharger 5. However, in another example, a high pressure compressor (not shown) of a high pressure electric supercharger (not shown) and a low pressure compressor (not shown) of a low pressure electric supercharger (not shown) are used. The internal combustion engine supercharging system according to the first embodiment can be applied to the internal combustion engine supercharging system. In still another example, the high pressure compressor (not shown) of the high pressure electric supercharger (not shown) is used. And the supercharging system for the internal combustion engine of the first embodiment can be applied to the supercharging system for the internal combustion engine having the low pressure compressor 5a of the low pressure turbocharger 5. In another example, the first embodiment is applied to a supercharging system for an internal combustion engine having a high-pressure compressor 4a of a high-pressure turbocharger 4 and a low-pressure compressor (not shown) of a low-pressure electric supercharger (not shown). A supercharging system for an internal combustion engine can also be applied.

In another example to which the internal combustion engine supercharging system according to the first embodiment is applied, the heat exchange medium passage 4a1f for the high-pressure compressor is located more than the position facing the high-pressure compressor impeller 4a2 in the high-pressure compressor housing 4a1. The heat exchange medium in the heat exchange medium passage 4a1f for the high-pressure compressor whose temperature is lower than that of the intake air is also compressed by the high-pressure compressor 4a and disposed at the upstream position (left side in FIG. 2). Or heated by the heat exchange medium in the heat exchange medium passage 4a1f for the high-pressure compressor having a temperature higher than that of the intake air.
Alternatively, in still another example to which the internal combustion engine supercharging system according to the first embodiment is applied, the high-pressure compressor heat exchange medium passage 4a1f is instead provided at a position other than the above-described position in the high-pressure compressor housing 4a1. It can also be arranged.

In another example to which the supercharging system for an internal combustion engine of the first embodiment is applied, the heat exchange medium passage 5a1f for the low-pressure compressor is located more than the position facing the low-pressure compressor impeller 5a2 in the low-pressure compressor housing 5a1. The heat exchange medium in the heat exchange medium passage 5a1f for the low-pressure compressor whose temperature is lower than that of the intake air before it is compressed by the low-pressure compressor 5a and disposed at the upstream position (left side in FIG. 3). It is possible to cool by the above, or to heat by the heat exchange medium in the heat exchange medium passage 5a1f for the low-pressure compressor having a temperature higher than that of the intake air.
Alternatively, in still another example to which the supercharging system for an internal combustion engine of the first embodiment is applied, instead of the low-pressure compressor heat exchange medium passage 5a1f at a position other than the above-described position in the low-pressure compressor housing 5a1. It can also be arranged.

In another example to which the internal combustion engine supercharging system of the first embodiment is applied, an intake bypass passage 6a, an intake bypass valve 6b, an exhaust bypass passage 7a, an exhaust bypass valve 7b, a waste gate passage 8a, and a waste gate are used. The valve 8b can be omitted.
Alternatively, in another example to which the internal combustion engine supercharging system of the first embodiment is applied, the exhaust bypass passage 7a, the exhaust bypass valve 7b, the waste gate passage 8a, and the waste gate valve 8b can be omitted.
Alternatively, in another example to which the internal combustion engine supercharging system of the first embodiment is applied, the intake bypass passage 6a, the intake bypass valve 6b, the waste gate passage 8a, and the waste gate valve 8b can be omitted.
Alternatively, in another example to which the internal combustion engine supercharging system of the first embodiment is applied, the intake bypass passage 6a, the intake bypass valve 6b, the exhaust bypass passage 7a, and the exhaust bypass valve 7b can be omitted.
Alternatively, in another example to which the supercharging system for an internal combustion engine of the first embodiment is applied, an intake bypass passage 6a, an intake bypass valve 6b, an exhaust bypass passage 7a, an exhaust bypass valve 7b, a waste gate passage 8a, and a waste gate A variable nozzle mechanism (not shown) disposed in the exhaust gas inlet portion of the high-pressure turbine 4 c in order to adjust the flow rate of the exhaust gas supplied to the high-pressure turbine 4 c of the high-pressure turbocharger 4 while omitting the valve 8 b. Can also be provided.
Alternatively, in another example to which the supercharging system for an internal combustion engine of the first embodiment is applied, an intake bypass passage 6a, an intake bypass valve 6b, an exhaust bypass passage 7a, an exhaust bypass valve 7b, a waste gate passage 8a, and a waste gate A variable nozzle mechanism (not shown) disposed in the exhaust gas inlet portion of the low-pressure turbine 5 c in order to adjust the flow rate of the exhaust gas supplied to the low-pressure turbine 5 c of the low-pressure turbocharger 5 while omitting the valve 8 b. Can also be provided.

Hereinafter, a second embodiment of the supercharging system for an internal combustion engine of the present invention will be described.
The main part of an example to which the supercharging system for an internal combustion engine of the second embodiment is applied is an example of an example to which the supercharging system for the internal combustion engine of the first embodiment shown in FIG. It is configured in the same way as the main part. Therefore, according to the supercharging system for an internal combustion engine of the second embodiment, the same effects as those of the supercharging system for the internal combustion engine of the first embodiment described above can be obtained except for the points described below.

FIG. 5 is a schematic block diagram of another main part of an example to which the internal combustion engine supercharging system of the second embodiment is applied.
In the example shown in FIG. 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, a heat exchange medium passage 4a1f formed in the high pressure compressor housing 4a1 in the heat exchange medium circulation path 10 and a low pressure A low-pressure compressor heat exchange medium passage 5a1f formed in the compressor housing 5a1, a heat exchange medium temperature adjusting device 10a for adjusting the temperature of the heat exchange medium, and a pump 10b are provided. In the example shown in FIG. 5 to which the internal combustion engine supercharging system is applied, the heat exchange medium circulation path 10 is formed in the high pressure compressor heat exchange medium passage 4a1f formed in the high pressure compressor housing 4a1 and the low pressure compressor housing 5a1. Heat exchange medium passage 5a1f for low pressure compressor and heat exchange medium temperature for adjusting the temperature of the heat exchange medium And adjusting device 10a, a pump 10b, and the internal combustion engine body 1 and the cooling water passage 1a formed in (FIG. 1 and see FIG. 5) is provided, as a heat exchange medium, the engine cooling water is used.
That is, in the example shown in FIG. 4 to which the supercharging system for the internal combustion engine of the first embodiment is applied, the engine coolant circulation for the heat exchange medium circulation path 10 to cool the internal combustion engine body 1 (see FIG. 1). In the example shown in FIG. 5 to which the internal combustion engine supercharging system according to the second embodiment is applied, instead of the passage (not shown), instead of the heat exchange medium circulation passage 10, The part constitutes the engine coolant circulation path.
That is, in the example shown in FIG. 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, as the heat exchange medium temperature adjusting device 10a, for example, separately from an engine coolant radiator (not shown). Although the provided radiator is used, in the example shown in FIG. 5 to which the internal combustion engine supercharging system of the second embodiment is applied, an engine cooling water radiator is used instead as the heat exchange medium temperature adjusting device 10a. Used.
Specifically, in the example shown in FIG. 5 to which the internal combustion engine supercharging system of the second embodiment is applied, the heat exchange medium temperature adjustment device 10a and the pump 10b are connected via the heat exchange medium passage 10c1, The pump 10b and the low-pressure compressor heat exchange medium passage 5a1f of the low-pressure compressor housing 5a1 are connected via the heat exchange medium passage 10c2, and the low-pressure compressor heat exchange medium passage 5a1f and the high-pressure compressor heat exchange medium passage of the high-pressure compressor housing 4a1. 4a1f is connected via the heat exchange medium passage 10c3, the high pressure compressor heat exchange medium passage 4a1f and the heat exchange medium temperature adjusting device 10a are connected via the heat exchange medium passage 10c4, and the heat exchange medium passage 10c2 and the internal combustion The cooling water passage 1a of the engine body 1 is connected via a heat exchange medium passage 10c5. It is connected via a cooling water passage 1a and the heat exchange medium passage 10c4 exchange heat medium passage 10C6.

In the example shown in FIG. 5 to which the internal combustion engine supercharging system of the second embodiment is applied, for example, since the outside air temperature is higher than a preset threshold, the high pressure compressor 4a (see FIG. 1 and FIG. 2) When the intake air supplied and the intake air supercharged by the low-pressure compressor 5a (see FIGS. 1 and 3) need to be cooled, and the internal combustion engine body 1 (see FIGS. 1 and 5) needs to be cooled, The engine cooling water radiator functioning as the heat exchange medium temperature adjusting device 10a reduces the temperature of the engine cooling water functioning as the heat exchange medium. That is, the heat exchange medium (engine cooling water) in the high-pressure compressor heat exchange medium passage 4a1f and the heat exchange medium (engine cooling water) in the low-pressure compressor heat exchange medium passage 5a1f function as the cooling medium.
Furthermore, in the example shown in FIG. 5 to which the internal combustion engine supercharging system according to the second embodiment is applied, for example, since the outside air temperature is lower than a preset threshold, the intake air and the low pressure that are supercharged by the high pressure compressor 4a When it is necessary to heat the intake air supercharged by the compressor 5a, the temperature of the heat exchange medium (engine cooling water) is raised by the heat exchange medium temperature adjusting device 10a, and the internal combustion engine main body 1 heats the internal combustion engine. In the cooling water passage 1a of the engine body 1, the temperature of the heat exchange medium (engine cooling water) is raised. That is, the heat exchange medium (engine cooling water) in the high-pressure compressor heat exchange medium passage 4a1f and the heat exchange medium (engine cooling water) in the low-pressure compressor heat exchange medium passage 5a1f function as heating media.
In the example shown in FIG. 5 to which the internal combustion engine supercharging system of the second embodiment is applied, heat exchange is performed in the same manner as the example shown in FIG. 4 to which the internal combustion engine supercharging system of the first embodiment is applied. In order to increase the temperature of the heat exchange medium (engine cooling water) circulating through the medium circulation path 10, for example, a heater (not shown) configured in the same manner as a known electric heater adjusts the temperature of the heat exchange medium. In another example to which the supercharging system for an internal combustion engine according to the second embodiment is applied, a heater for raising the temperature of the heat exchange medium (engine cooling water) is provided instead. It can be omitted. In another example to which the internal combustion engine supercharging system of the second embodiment is applied, the temperature of the heat exchange medium (engine cooling water) is not raised by the heat of the heater, but by the heat of the internal combustion engine body 1. The temperature of the heat exchange medium (engine cooling water) is raised, and the intake air supercharged by the high-pressure compressor 4a and the intake air supercharged by the low-pressure compressor 5a are heated.

Hereinafter, a third embodiment of the supercharging system for an internal combustion engine of the present invention will be described.
The main part of an example to which the supercharging system for an internal combustion engine of the third embodiment is applied is an example of an example to which the supercharging system for the internal combustion engine of the first embodiment shown in FIG. It is configured in the same way as the main part. Therefore, according to the supercharging system for the internal combustion engine of the third embodiment, the same effects as those of the supercharging system for the internal combustion engine of the first embodiment described above can be obtained except for the points described below.

FIG. 6 is a schematic block diagram of another main part of an example to which the supercharging system for an internal combustion engine of the third embodiment is applied.
In the example shown in FIG. 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, a heat exchange medium passage 4a1f formed in the high pressure compressor housing 4a1 in the heat exchange medium circulation path 10 and a low pressure A low-pressure compressor heat exchange medium passage 5a1f formed in the compressor housing 5a1, a heat exchange medium temperature adjustment device 10a for adjusting the temperature of the heat exchange medium, and a pump 10b are provided. In the example shown in FIG. 6 to which the internal combustion engine supercharging system is applied, the heat exchange medium circulation path 10 is formed in the high pressure compressor heat exchange medium passage 4a1f formed in the high pressure compressor housing 4a1 and the low pressure compressor housing 5a1. Heat exchange medium passage 5a1f for low pressure compressor and heat exchange medium temperature for adjusting the temperature of the heat exchange medium An adjustment device 10a, a pump 10b, and another heat exchange medium temperature adjustment device 10a ′ for adjusting the temperature of the heat exchange medium are provided, and the other heat exchange medium temperature adjustment device 10a ′ is provided in the high-pressure compressor housing 4a1. The high-pressure compressor heat exchange medium passage 4a1f and the low-pressure compressor heat exchange medium passage 5a1f of the low-pressure compressor housing 5a1 are disposed. The other heat exchange medium temperature adjustment device 10a ′ can be configured in the same manner as the heat exchange medium temperature adjustment device 10a, for example.
Specifically, in the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, the heat exchange medium temperature adjusting device 10a and the pump 10b are connected via the heat exchange medium passage 10c1, The pump 10b and the low-pressure compressor heat exchange medium passage 5a1f of the low-pressure compressor housing 5a1 are connected via the heat exchange medium passage 10c2, and the low-pressure compressor heat exchange medium passage 5a1f and the other heat exchange medium temperature adjusting device 10a ′ are connected. The heat exchange medium passage 10c3 is connected, the other heat exchange medium temperature adjusting device 10a 'and the high pressure compressor heat exchange medium passage 4a1f of the high pressure compressor housing 4a1 are connected via the heat exchange medium passage 10c3', and the high pressure The heat exchange medium passage 4a1f for the compressor and the heat exchange medium temperature adjusting device 10a pass through the heat exchange medium passage 10c4. It is connected to.

In the example shown in FIG. 6 to which the supercharging system for an internal combustion engine of the third embodiment is applied, for example, since the outside air temperature is higher than a preset threshold value, the high pressure compressor 4a (see FIGS. 1 and 2) When it is necessary to cool the supplied intake air and the intake air supercharged by the low-pressure compressor 5a (see FIGS. 1 and 3), the heat exchange medium temperature adjusting device 10a and the other heat exchange medium temperature adjusting device 10a ′ The temperature of the heat exchange medium is lowered, and the heat exchange medium in the high pressure compressor heat exchange medium passage 4a1f and the heat exchange medium in the low pressure compressor heat exchange medium passage 5a1f function as a cooling medium.
Furthermore, in the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, for example, the outside air temperature is lower than a preset threshold value, so that the intake air and the low pressure that are supercharged by the high pressure compressor 4a When it is necessary to heat the intake air supercharged by the compressor 5a, the temperature of the heat exchange medium is raised by the heat exchange medium temperature adjusting device 10a and the other heat exchange medium temperature adjusting device 10a ', and the heat for the high pressure compressor The heat exchange medium in the exchange medium passage 4a1f and the heat exchange medium in the heat exchange medium passage 5a1f for the low-pressure compressor function as a heating medium.
In the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, the heat exchange medium is the heat exchange medium temperature adjusting device 10a, the low-pressure compressor heat exchange medium passage 5a1f, as shown by arrows. The other heat exchange medium temperature adjusting device 10a ′ and the heat exchange medium passage 4a1f for the high-pressure compressor are circulated through the heat exchange medium circulation path 10 in this order.

FIG. 7 shows the inside of the heat exchange medium circulation path 10 when the heat exchange medium is cooled by the heat exchange medium temperature adjusting device 10a in the example shown in FIG. 6 to which the supercharging system for an internal combustion engine of the third embodiment is applied. Temperature change of heat exchange medium and heat exchange medium when heat exchange medium is cooled by heat exchange medium temperature adjustment device 10a in the example shown in FIG. 4 to which the internal combustion engine supercharging system of the first embodiment is applied It is the figure which showed the temperature transition of the heat exchange medium in the circulation path. Specifically, in FIG. 7, the solid line indicates the temperature of the heat exchange medium in the heat exchange medium circuit 10 in the example illustrated in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, The broken line shows the temperature of the heat exchange medium in the heat exchange medium circulation path 10 in the example shown in FIG. 4 to which the internal combustion engine supercharging system of the first embodiment is applied.
In the example shown in FIG. 4 to which the supercharging system for an internal combustion engine of the first embodiment is applied, as shown by a broken line “first embodiment” in FIG. 7, the heat exchange medium is a heat exchange medium temperature adjustment device 10a. (Refer to FIG. 4 and FIG. 7) The temperature of the heat exchange medium decreases from the value Tw3 to the value Tw1 at the position of the heat exchange medium temperature adjusting device 10a. Next, at the positions of the heat exchange medium passage 10c1 (see FIGS. 4 and 7), the pump 10b (see FIGS. 4 and 7), and the heat exchange medium passage 10c2 (see FIGS. 4 and 7), the temperature of the heat exchange medium is The value Tw1 is maintained. Next, at the position of the heat exchange medium passage 5a1f (see FIGS. 4 and 7) for the low-pressure compressor, the temperature of the heat exchange medium rises from the value Tw1 to the value Tw2. Next, at the position of the heat exchange medium passage 10c3 (see FIGS. 4 and 7), the temperature of the heat exchange medium is maintained at the value Tw2. Next, at the position of the heat exchange medium passage 4a1f (see FIGS. 4 and 7) for the high-pressure compressor, the temperature of the heat exchange medium rises from the value Tw2 to the value Tw3. Next, the temperature of the heat exchange medium is maintained at the value Tw3 at the position of the heat exchange medium passage 10c4 (see FIGS. 4 and 7).
That is, in the example shown in FIGS. 4 and 7 to which the internal combustion engine supercharging system of the first embodiment is applied, the intake air and the high pressure compressor 4a (see FIGS. 1 and 3) in the low pressure compressor 5a (see FIGS. 1 and 3). When it is necessary to cool the intake air in FIG. 2, the temperature of the heat exchange medium has a value at the position of the heat exchange medium passage 4a1f for the high-pressure compressor, as shown by a broken line “first embodiment” in FIG. As a result, the intake air in the high-pressure compressor 4a may not be sufficiently cooled.

On the other hand, in the example shown in FIG. 6 to which the supercharging system for an internal combustion engine of the third embodiment is applied, as shown by a solid line “third embodiment” in FIG. Cooled by the device 10a (see FIG. 6 and FIG. 7), the temperature of the heat exchange medium decreases from the value Tw2 to the value Tw1 at the position of the heat exchange medium temperature adjusting device 10a. Next, at the positions of the heat exchange medium passage 10c1 (see FIGS. 6 and 7), the pump 10b (see FIGS. 6 and 7), and the heat exchange medium passage 10c2 (see FIGS. 6 and 7), the temperature of the heat exchange medium is The value Tw1 is maintained. Next, at the position of the heat exchange medium passage 5a1f (see FIGS. 6 and 7) for the low-pressure compressor, the temperature of the heat exchange medium rises from the value Tw1 to the value Tw2. Next, at the position of the heat exchange medium passage 10c3 (see FIGS. 6 and 7), the temperature of the heat exchange medium is maintained at the value Tw2. Then, the heat exchange medium is cooled by another heat exchange medium temperature adjustment device 10a ′ (see FIGS. 6 and 7), and the temperature of the heat exchange medium is the value Tw2 at the position of the other heat exchange medium temperature adjustment device 10a ′. To the value Tw1. Next, at the position of the heat exchange medium passage 10c3 ′ (see FIGS. 6 and 7), the temperature of the heat exchange medium is maintained at the value Tw1. Next, at the position of the heat exchange medium passage 4a1f (see FIGS. 6 and 7) for the high-pressure compressor, the temperature of the heat exchange medium rises from the value Tw1 to the value Tw2. Next, at the position of the heat exchange medium passage 10c4 (see FIGS. 6 and 7), the temperature of the heat exchange medium is maintained at the value Tw2.
That is, in the example shown in FIGS. 6 and 7 to which the internal combustion engine supercharging system of the third embodiment is applied, the intake air and the high pressure compressor 4a (see FIGS. 1 and 3) in the low pressure compressor 5a (see FIGS. 1 and 3). When it is necessary to cool the intake air in FIG. 2, the temperature of the heat exchange medium is measured at the position of the heat exchange medium passage 4a1f for the high-pressure compressor, as shown by the solid line “third embodiment” in FIG. Tw2 can be suppressed, and as a result, the intake air in the high-pressure compressor 4a can be sufficiently cooled.

That is, in the example shown in FIGS. 6 and 7 to which the internal combustion engine supercharging system of the third embodiment is applied, the heat exchange medium is the heat exchange medium temperature adjusting device 10a, the low pressure compressor heat exchange medium passage 5a1f, Since the heat exchange medium circulation path 10 is circulated in the order of the other heat exchange medium temperature adjusting device 10a ′ and the high pressure compressor heat exchange medium path 4a1f, the temperature of the heat exchange medium in the heat exchange medium circulation path 10 is reduced to the low pressure compressor 5a ( When the temperature of the intake air in the high pressure compressor 4a (see FIGS. 1 and 2) is lower than that of the intake air in the high pressure compressor 4a (see FIGS. 1 and 2), the temperature rises when flowing through the heat exchange medium passage 5a1f for the low pressure compressor. The heat exchange medium is cooled when it flows through the other heat exchange medium temperature adjusting device 10a ′, and flows through the high-pressure compressor heat exchange medium passage 4a1f.
Therefore, in the example shown in FIG. 6 and FIG. 7 to which the supercharging system for an internal combustion engine of the third embodiment is applied, the heat exchange medium flowing through the heat exchange medium passage 5a1f for the low-pressure compressor is another heat exchange medium temperature adjustment. The possibility that the intake air in the high-pressure compressor 4a cannot be sufficiently cooled when the intake air in the high-pressure compressor 4a needs to be cooled is suppressed as compared with the case where the intake air in the high-pressure compressor 4a needs to be cooled, rather than the case where the intake air in the high-pressure compressor 4a flows. be able to.
Furthermore, in the example shown in FIG. 6 to which the supercharging system for an internal combustion engine of the third embodiment is applied, as described above, the heat exchange medium is the heat exchange medium temperature adjusting device 10a, the heat exchange medium passage for the low-pressure compressor. 5a1f, the other heat exchange medium temperature adjusting device 10a ′, and the heat exchange medium passage 4a1f for the high pressure compressor are circulated through the heat exchange medium circulation path 10 in this order, so that the temperature of the heat exchange medium in the heat exchange medium circulation path 10 is low-pressure compressor. When the temperature of the intake air in 5a and the temperature of the intake air in the high-pressure compressor 4a are higher, the heat exchange medium that has cooled down when flowing through the heat exchange medium passage 5a1f for the low-pressure compressor is another heat exchange medium temperature adjusting device 10a ′. And flows through the heat exchange medium passage 4a1f for the high-pressure compressor.
Therefore, in the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, the heat exchange medium flowing through the low-pressure compressor heat exchange medium passage 5a1f is another heat exchange medium temperature adjustment device 10a ′. The possibility that the intake air in the high-pressure compressor 4a cannot be sufficiently heated when it is necessary to heat the intake air in the high-pressure compressor 4a can be suppressed as compared with the case where the intake air in the high-pressure compressor 4a needs to be heated. .

Hereinafter, a fourth embodiment of the supercharging system for an internal combustion engine of the present invention will be described.
The main part of an example to which the supercharging system for an internal combustion engine of the fourth embodiment is applied is an example of an example to which the supercharging system for the internal combustion engine of the first embodiment shown in FIG. The other main part of an example to which the supercharging system for internal combustion engines of 4th Embodiment was applied is the same as that of the main part, except for the point mentioned later, of 3rd Embodiment shown in FIG. It is comprised similarly to the other main part of an example to which the supercharging system for internal combustion engines was applied. Therefore, according to the supercharging system for the internal combustion engine of the fourth embodiment, the same effects as those of the supercharging system for the internal combustion engine of the first and third embodiments described above can be obtained except for the points described below. .

FIG. 8 is a schematic block diagram of another main part of an example to which the supercharging system for an internal combustion engine of the fourth embodiment is applied.
In the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, the heat exchange medium circulation path 10 has a high pressure compressor heat exchange medium passage 4a1f formed in the high pressure compressor housing 4a1, and a low pressure. Low-pressure compressor heat exchange medium passage 5a1f formed in compressor housing 5a1, heat exchange medium temperature adjusting device 10a for adjusting the temperature of the heat exchange medium, pump 10b, and other heat exchange for adjusting the temperature of the heat exchange medium In the example shown in FIG. 8 to which the supercharging system for an internal combustion engine of the fourth embodiment is applied, the medium temperature adjusting device 10a ′ is provided in the high-pressure compressor housing 4a1 in the heat exchange medium circulation path 10. Heat for low pressure compressor formed in heat exchange medium passage 4a1f for high pressure compressor and low pressure compressor housing 5a1 formed Exchange medium passage 5a1f, heat exchange medium temperature adjustment device 10a for adjusting the temperature of the heat exchange medium, pump 10b, another heat exchange medium temperature adjustment device 10a ′ for adjusting the temperature of the heat exchange medium, and the internal combustion engine body 1 (see FIG. 1 and FIG. 8), and a cooling water passage 1a is provided, and engine cooling water is used as a heat exchange medium.
That is, in the example shown in FIG. 6 to which the supercharging system for an internal combustion engine of the third embodiment is applied, the engine coolant circulation for the heat exchange medium circulation path 10 to cool the internal combustion engine body 1 (see FIG. 1). In the example shown in FIG. 8 to which the supercharging system for the internal combustion engine of the fourth embodiment is applied, instead of the passage (not shown), instead of the heat exchange medium circulation passage 10, The part constitutes the engine coolant circulation path.
That is, in the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied, as the heat exchange medium temperature adjusting device 10a, for example, separately from an engine coolant radiator (not shown). Although the provided radiator is used, in the example shown in FIG. 8 to which the internal combustion engine supercharging system of the fourth embodiment is applied, an engine cooling water radiator is used instead as the heat exchange medium temperature adjusting device 10a. Used.
Specifically, in the example shown in FIG. 8 to which the internal combustion engine supercharging system of the fourth embodiment is applied, the heat exchange medium temperature adjusting device 10a and the pump 10b are connected via the heat exchange medium passage 10c1, The pump 10b and the low-pressure compressor heat exchange medium passage 5a1f of the low-pressure compressor housing 5a1 are connected via the heat exchange medium passage 10c2, and the low-pressure compressor heat exchange medium passage 5a1f and the other heat exchange medium temperature adjusting device 10a ′ are connected. The heat exchange medium passage 10c3 is connected, the other heat exchange medium temperature adjusting device 10a 'and the high pressure compressor heat exchange medium passage 4a1f of the high pressure compressor housing 4a1 are connected via the heat exchange medium passage 10c3', and the high pressure The heat exchange medium passage 4a1f for the compressor and the heat exchange medium temperature adjusting device 10a pass through the heat exchange medium passage 10c4. The heat exchange medium passage 10c2 and the cooling water passage 1a of the internal combustion engine body 1 are connected via the heat exchange medium passage 10c5, and the cooling water passage 1a and the heat exchange medium passage 10c4 are connected to the heat exchange medium passage 10c6. Connected through.

In the example shown in FIG. 8 to which the internal combustion engine supercharging system of the fourth embodiment is applied, for example, since the outside air temperature is higher than a preset threshold, the high pressure compressor 4a (see FIGS. 1 and 2) When it is necessary to cool the intake air supplied and the intake air supercharged by the low-pressure compressor 5a (see FIGS. 1 and 3) and the internal combustion engine body 1 (see FIGS. 1 and 8) needs to be cooled, The engine cooling water radiator that functions as the heat exchange medium temperature adjustment device 10a and the other heat exchange medium temperature adjustment device 10a ′ lower the temperature of the engine cooling water that functions as the heat exchange medium. That is, the heat exchange medium (engine cooling water) in the high-pressure compressor heat exchange medium passage 4a1f and the heat exchange medium (engine cooling water) in the low-pressure compressor heat exchange medium passage 5a1f function as the cooling medium.
Further, in the example shown in FIG. 8 to which the internal combustion engine supercharging system of the fourth embodiment is applied, for example, the outside air temperature is lower than a preset threshold value, so that the intake air and the low pressure that are supercharged by the high pressure compressor 4a When it is necessary to heat the intake air supercharged by the compressor 5a, the temperature of the heat exchange medium (engine coolant) is raised by the heat exchange medium temperature adjustment device 10a and the other heat exchange medium temperature adjustment device 10a ′. At the same time, the heat of the internal combustion engine body 1 raises the temperature of the heat exchange medium (engine cooling water) in the cooling water passage 1a of the internal combustion engine body 1. That is, the heat exchange medium (engine cooling water) in the high-pressure compressor heat exchange medium passage 4a1f and the heat exchange medium (engine cooling water) in the low-pressure compressor heat exchange medium passage 5a1f function as heating media.
In the example shown in FIG. 8 to which the internal combustion engine supercharging system of the fourth embodiment is applied, heat exchange is performed in the same manner as the example shown in FIG. 6 to which the internal combustion engine supercharging system of the third embodiment is applied. In order to increase the temperature of the heat exchange medium (engine cooling water) circulating through the medium circulation path 10, for example, a heater (not shown) configured in the same manner as a known electric heater adjusts the temperature of the heat exchange medium. Although it is provided in the apparatus 10a and the other heat exchange medium temperature adjustment apparatus 10a ', in another example to which the supercharging system for the internal combustion engine of the fourth embodiment is applied, instead of the heat exchange medium (engine cooling The heater for raising the temperature of water) can be omitted. In another example to which the internal combustion engine supercharging system of the fourth embodiment is applied, the temperature of the heat exchange medium (engine cooling water) is not raised by the heat of the heater, but by the heat of the internal combustion engine body 1. The temperature of the heat exchange medium (engine cooling water) is raised, and the intake air supercharged by the high-pressure compressor 4a and the intake air supercharged by the low-pressure compressor 5a are heated.

  In the fifth embodiment, the above-described first to fourth embodiments and their respective examples can be appropriately combined.

DESCRIPTION OF SYMBOLS 1 Internal combustion engine main body 1a Cooling water passage 2 Intake passage 3 Exhaust passage 4 High pressure turbocharger 4a High pressure compressor 4a1 High pressure compressor housing 4a1a Inlet passage 4a1b Scroll passage 4a1c Shroud portion 4a1d Shroud surface 4a1e Diffuser portion 4a1f High pressure compressor heat exchange medium passage 4a2 High pressure Compressor impeller 4b Shaft 4b1 Center axis 4c High pressure turbine 4c2 High pressure turbine impeller 5 Low pressure turbocharger 5a Low pressure compressor 5a1 Low pressure compressor housing 5a1a Inlet passage 5a1b Scroll passage 5a1c Shroud portion 5a1d Shroud surface 5a1e Diffuser portion 5a1f Heat exchange passage for low pressure compressor 5 Compressor impeller 5b Shaft 5b1 Center axis 5c Low pressure turbine 5c2 Low pressure turbine impeller 6a Intake bypass passage 6b Intake bypass valve 7a Exhaust bypass passage 7b Exhaust bypass valve 8a Waste gate passage 8b Waste gate valve 10 Heat exchange medium circulation passage 10a, 10a 'Heat exchange medium temperature adjusting device 10b Pump 10c1, 10c2, 10c3, 10c3 ′, 10c4 Heat exchange medium passage 10c5, 10c6 Heat exchange medium passage 50 ECU

Claims (7)

An internal combustion engine body;
An intake passage connected to the internal combustion engine body;
A high-pressure compressor disposed in the intake passage;
A low-pressure compressor disposed upstream of the high-pressure compressor in the intake passage;
A high-pressure compressor heat exchange medium passage formed in a high-pressure compressor housing in which a part of the intake passage is formed, and a low-pressure compressor formed in a low-pressure compressor housing in which a portion of the intake passage is formed. A heat exchange medium passage having a heat exchange medium passage and a heat exchange medium temperature adjusting device for adjusting the temperature of the heat exchange medium;
The heat exchange medium circulates through the heat exchange medium circulation path in the order of the heat exchange medium temperature adjusting device, the low pressure compressor heat exchange medium path, and the high pressure compressor heat exchange medium path ,
The heat exchange medium circuit has another heat exchange medium temperature adjustment device for adjusting the temperature of the heat exchange medium,
The heat exchange medium passes through the heat exchange medium circulation path in the order of the heat exchange medium temperature adjustment device, the heat exchange medium passage for the low pressure compressor, the other heat exchange medium temperature adjustment device, and the heat exchange medium passage for the high pressure compressor. circulation to supercharging system for an internal combustion engine according to claim Rukoto. The heat exchange medium is a cooling medium;
The supercharging system for an internal combustion engine according to claim 1, wherein the heat exchange medium temperature adjusting device reduces the temperature of the cooling medium. The heat exchange medium is a heating medium;
The supercharging system for an internal combustion engine according to claim 1, wherein the heat exchange medium temperature adjusting device increases the temperature of the heating medium.   The heat exchange medium passage for the high-pressure compressor is disposed at a first position facing the high-pressure compressor impeller in the high-pressure compressor housing, or at a position upstream of the first position. Item 2. The supercharging system for an internal combustion engine according to Item 1.   The heat exchange medium passage for the low-pressure compressor is arranged at a second position facing the low-pressure compressor impeller in the low-pressure compressor housing, or at a position upstream of the second position. Item 2. The supercharging system for an internal combustion engine according to Item 1.   2. The internal combustion engine according to claim 1, wherein the heat exchange medium passage for the high-pressure compressor is formed along a shroud surface that is a surface of a shroud portion facing the high-pressure compressor impeller in the high-pressure compressor housing. Supercharging system for engines.   2. The internal combustion engine according to claim 1, wherein the heat exchange medium passage for the low-pressure compressor is formed along a shroud surface that is a surface of a shroud portion facing the low-pressure compressor impeller in the low-pressure compressor housing. Supercharging system for engines.

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