Internal combustion engine for a motor vehicle, method for operating such an internal combustion engine, and motor vehicle

Abstract

The invention relates to an internal combustion engine (10), comprising: an intake tract (18), through which air can flow and by means of which the air can be introduced into at least one combustion chamber (16); a compressor (24) for compressing the air; and a diverter device (42), which has a diverter line (44) by means of which at least some of the air flowing through the intake tract (18) can be branched off from the intake tract (18) at a branching point (A2) arranged downstream of the compressor (24) and can be introduced into the intake tract (18) at an introduction point (E2) arranged upstream of the compressor (24). A diverter valve (48) which is arranged in the diverter line (44) is provided, by means of which diverter valve an amount of the air flowing through the diverter line (44) can be set. A throttle valve (46) which is arranged in the intake tract (18) upstream of the at least one combustion chamber (16) and downstream of the branching point (A2) is provided, by means of which throttle valve an amount of the air to be introduced into the at least one combustion chamber (16) can be set.

Description

[0001] Internal combustion engine for a motor vehicle, method for operating such an engine

[0002] Internal combustion engine and motor vehicle

[0003] The invention relates to an internal combustion engine for a motor vehicle according to the preamble of claim 1. Furthermore, the invention relates to a method for operating such an internal combustion engine according to the preamble of claim 2. The invention also relates to a motor vehicle with such an internal combustion engine.

[0004] DE 102022 001 621 A1 discloses an internal combustion engine for a motor vehicle as known, with an intake tract through which combustion air can flow, by means of which the combustion air can be introduced into combustion chambers of the internal combustion engine.

[0005] DE 10 2017200 800 A1 discloses an internal combustion engine for a motor vehicle with an intake manifold through which air can be introduced into at least one combustion chamber of the internal combustion engine. A compressor is arranged in the intake manifold for compressing the air flowing through it, the compressor being part of an exhaust gas turbocharger. A bypass air system includes a bypass air duct by means of which at least a portion of the air flowing through the intake manifold can be diverted from the intake manifold at a branch point located downstream of the compressor and introduced into the intake manifold at an inlet point located upstream of the compressor. A bypass air valve is arranged in the bypass air duct by means of which the amount of air flowing through the bypass air duct can be adjusted.In the intake manifold, a throttle valve is arranged upstream of the at least one combustion chamber and downstream of the branch point, by means of which the quantity of air to be introduced into the at least one combustion chamber can be adjusted. An electric motor is associated with the compressor, by means of which the compressor can be driven. The internal combustion engine can be operated in a heating mode in which firing is suspended, the throttle valve is closed, the bypass valve is fully open, and the electric motor drives the compressor, whereby the compressor delivers air that can be heated by the heating mode and circulates in a closed loop. The loop comprises a section of the intake manifold extending from the inlet to the branch point, within which the compressor is arranged, and the bypass duct extending from the branch point to the inlet.The inlet point is located downstream of an air filter situated in the intake tract.

[0006] The object of the present invention is to provide an internal combustion engine for a motor vehicle, a method for operating such an internal combustion engine, and a motor vehicle with such an internal combustion engine, in such a way as to avoid excessive condensation.

[0007] This problem is solved by an internal combustion engine with the features of claim 1, by a method with the features of claim 2, and by a motor vehicle with the features of claim 5. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0008] A first aspect of the invention relates to an internal combustion engine, also referred to as an internal combustion engine or combustion power unit, for a motor vehicle, also referred to simply as a vehicle. This means that the motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, in its fully manufactured state, has the internal combustion engine and can be driven by means of the internal combustion engine. Preferably, the internal combustion engine is designed as a reciprocating piston engine, that is, as a reciprocating piston machine.

[0009] The internal combustion engine has an intake manifold, also known as the intake tract, through which air, also called combustion air, flows. The air flowing through the intake manifold can be introduced into at least one combustion chamber of the internal combustion engine. This means that the internal combustion engine has at least one combustion chamber in which combustion processes take place during operation. In each combustion process, a fuel-air mixture, also simply called a mixture, is burned, thereby driving, for example, a piston of the internal combustion engine that partially defines the combustion chamber.The piston is, for example, connected via a connecting rod to an output shaft of the internal combustion engine, which may be a crankshaft. This output shaft can provide drive torque to propel the vehicle. Driving the piston drives the output shaft, which in turn drives the vehicle.

[0010] The internal combustion engine also has a compressor located in the intake manifold, by means of which the air flowing through the intake manifold can be compressed. In particular, the compressor has a compressor wheel located in the intake manifold, by means of which the air flowing through the intake manifold can be compressed by driving the compressor wheel.

[0011] The internal combustion engine also features a recirculating air system, also known as a blow-off valve system. This system includes a blow-off air duct through which at least a portion of the air flowing through the intake manifold can be diverted at a branch point. The air diverted from the intake manifold and introduced into the blow-off air duct can flow through the duct and be guided to an inlet point where it can be introduced back into the intake manifold. In the direction of airflow through the intake manifold, the branch point is located downstream of the compressor, i.e., downstream of the compressor wheel. In the direction of airflow through the intake manifold, the inlet point is located upstream of the compressor, i.e., upstream of the compressor wheel.In particular, it is intended that the recirculating air line is fluidically connected to the intake tract at the branch point and at the inlet point.

[0012] The bypass air system also includes a bypass air valve located in the bypass air duct, by means of which the amount of air flowing through the bypass air duct can be adjusted. For example, the bypass air valve can be adjusted between a closed position and at least one open position. In the closed position, the bypass air valve, for example, fluidically blocks the bypass air duct, in particular completely, so that no air can flow through the bypass air duct. In the open position, the bypass air valve releases the bypass air duct, which is thereby allowed to be filled with air. The open position of the bypass air valve is also referred to as the first open position, and the closed position of the bypass air valve is also referred to as the first closed position.

[0013] For example, the diverter valve is an electrically operated valve, and therefore an electric valve. This means, for instance, that the diverter valve can be switched electrically, that is, by supplying the diverter valve with electrical energy, between the closed and open positions. In particular, the diverter valve can be adjusted between the closed and open positions by actuating it, especially electrically.

[0014] The internal combustion engine also has a throttle valve, which is arranged upstream of the at least one combustion chamber, in particular upstream of all combustion chambers of the internal combustion engine, and downstream of the branch point, in the direction of airflow through the intake manifold. The throttle valve allows the amount of air introduced into the at least one combustion chamber to be adjusted. For example, the throttle valve can be adjusted between a first position and a second position. In the second position, for example, the throttle valve opens the intake manifold more freely than in the first position, so that, conversely, the throttle valve in the first position restricts the intake manifold more fluidly than in the second position. For example, the first position is a second open position of the throttle valve, which, for example, in its second open position restricts the intake manifold, in particular completely, fluidly.Furthermore, it is conceivable that the first position of the throttle valve is a second open position, which in its second open position allows air to flow through the intake manifold, but less strongly than in the second position. The second position of the throttle valve could, for example, be a third open position, which in its third open position allows air to flow through the intake manifold more strongly than in the first position.In other words, for example, in the first position, the throttle valve limits a first flow cross-section, larger than zero and through which air can flow, at least partially and / or directly, and for example, in the second position, the throttle valve limits a second flow cross-section, larger than zero and through which air can flow, particularly directly and / or at least partially, wherein the second flow cross-section is larger than the first flow cross-section. To avoid undesirable, excessive condensation in the intake tract, the invention provides that an electric machine is associated with the compressor, in particular the compressor wheel, by means of which the compressor, in particular the compressor wheel, can be driven.For this purpose, the electric machine can be operated in motor mode, thus functioning as an electric motor, which drives the compressor, and therefore the compressor wheel. To operate the electric machine in motor mode, it must be supplied with electrical energy.

[0015] Furthermore, according to the invention, the internal combustion engine can be operated in a controlled heating mode. This means that the heating mode of the internal combustion engine is not a random, i.e., not a randomly occurring event, but rather the heating mode can be deliberately induced by operating the internal combustion engine. In the heating mode, the internal combustion engine is not fired. This means that no combustion processes take place in the at least one combustion chamber, and in particular in the internal combustion engine as a whole, during the heating mode. In other words, it is preferably provided that no combustion processes take place in any of the combustion chambers of the internal combustion engine.During the heating operation, the throttle valve is closed, preferably completely, so that it is in the aforementioned first position. During the heating operation, the bypass valve is open, so that it is in the first open position. During the heating operation, the electric motor drives the compressor, i.e., the compressor wheel, causing the compressor to deliver air that can be heated in a controlled manner during the heating operation. This air circulates in a closed loop, which includes a continuous, and therefore uninterrupted, section of the intake tract extending from the inlet to the branch point, within which the compressor is located, and the bypass air duct extending from the branch point to the inlet.Thus, the air supplied by the compressor during heating operation flows in a closed loop, from the inlet point, through the compressor, to the branch point, and from the branch point through the recirculating air duct before returning to the inlet point. This air circulation heats the air in a controlled manner, allowing at least a portion of the intake tract, encompassing the entire loop, to be heated. This prevents the formation of excessive condensate in this section of the intake tract, thereby also avoiding undesirable effects that could otherwise result from condensation.In particular, the heating operation makes it possible to heat the air conveyed by the compressor to at least 160 degrees Celsius within a few seconds, thereby heating at least the aforementioned section of the intake tract to at least 160 degrees Celsius. This prevents excessive condensation in that section of the intake tract.

[0016] In other words, according to the invention, the internal combustion engine is designed to operate in heating mode. For this purpose, the internal combustion engine has, for example, an electronic computing device, also referred to as engine control unit or control unit, by means of which, for example, software, also referred to as engine software, can be executed or is executed, wherein the heating mode is implemented in the engine software, so that by executing the engine software, the internal combustion engine can be operated or is operated in heating mode. For example, the engine software is stored in a data storage device of the control unit, which is, in particular, electrical or electronic.

[0017] The air compressed by the compressor is also referred to as charge air. Therefore, the air that can be diverted from the intake manifold at the branch point via the bypass line and reintroduced into the intake manifold at the inlet point is at least part of the charge air. Furthermore, at least a section of the intake manifold extending from the compressor to the branch point, as well as the bypass line (if applicable), belongs to a so-called charge air system of the internal combustion engine, meaning that the aforementioned section of the intake manifold and the bypass line constitute at least part of the charge air system. Thus, the system encompasses at least this part of the charge air system.Since the circulation of the air conveyed by the compressor during heating operation heats the air conveyed by the compressor during heating operation, and thus the circuit and at least part of the intake tract, at least the aforementioned part of the charge air path can be heated, so that excessive condensation can be avoided, at least in that part of the charge air path. The invention is based in particular on the understanding that excessive condensation, i.e., an excessive amount of condensate forming in the intake tract and thereby in the charge air path, can lead to undesirable effects. For example, the condensate can freeze and thus form frozen particles, especially ice particles, which can damage the compressor, especially the compressor wheel.The invention thus makes it possible to avoid excessive formation of frozen particles that could damage the compressor, so that the compressor can be particularly well protected.

[0018] In order to heat at least a specific section of the intake tract particularly effectively and thus prevent excessive condensation, the invention provides that the bypass valve is fully open, i.e., as far as possible, during the heating process. This means that, preferably, the bypass valve opens the bypass air duct to its maximum extent during the heating process.

[0019] The invention is further characterized in that the inlet point is arranged downstream of an air filter located in the intake tract, which allows the air and consequently at least the part of the intake tract to be heated particularly efficiently and effectively.

[0020] Finally, according to the invention, the compressor is a component of an exhaust gas turbocharger, which has a turbine arranged in an exhaust tract of the internal combustion engine and driven by the exhaust gas flowing through the exhaust tract of the internal combustion engine, by means of which the compressor can be driven. This allows the heating operation to be implemented in a particularly simple, effective and efficient manner.

[0021] A second aspect of the invention relates to a method for operating an internal combustion engine of a motor vehicle, in particular an internal combustion engine according to the first aspect of the invention. In this method, the internal combustion engine has an intake manifold through which air can flow, and through which the air can be introduced into at least one combustion chamber of the internal combustion engine. In this method, the internal combustion engine has a compressor arranged in the intake manifold for compressing the air flowing through the intake manifold. In this method, the internal combustion engine also has a recirculating air device, which has a recirculating air duct by means of which at least a portion of the air flowing through the intake manifold can be diverted from the intake manifold at a branch point arranged downstream of the compressor and introduced into the intake manifold at an inlet point arranged upstream of the compressor.The recirculating air system also includes a recirculating air valve arranged in the recirculating air duct, by means of which the quantity of air flowing through the recirculating air duct can be adjusted. In this method, the internal combustion engine has a throttle valve arranged in the intake manifold upstream of the at least one combustion chamber and downstream of the branch point, by means of which the quantity of air introduced into the at least one combustion chamber can be adjusted.

[0022] In order to advantageously avoid excessive condensation in the intake tract, the second aspect of the invention provides that an electric machine is associated with the compressor, by means of which the compressor can be driven.Furthermore, according to the invention, the internal combustion engine is specifically operated in a heating mode in which the combustion engine is not fired, i.e., in particular in all combustion chambers of the internal combustion engine, the throttle valve is completely closed, the bypass valve is open, and the electric motor drives the compressor, whereby the compressor delivers air which is specifically heated by means of the heating mode and circulates in a cycle in the heating mode, which comprises a length section of the intake tract extending from the inlet point to the branch point, in particular continuously and thus without interruption, in which the compressor is arranged, and the bypass air duct extending from the branch point to the inlet point, in particular without interruption.Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention and vice versa.

[0023] The feature that the throttle valve is completely closed during heating operation means that the throttle valve is in its maximum closed position, i.e., that the throttle valve completely blocks the intake tract fluidically or sets the smallest possible flow cross-section through which air can flow, optionally larger than zero, by means of the throttle valve. To particularly advantageously avoid excessive condensation in the intake tract, one embodiment of the second aspect of the invention provides that the vehicle is not driven by the internal combustion engine during the process.

[0024] Finally, it has proven particularly advantageous if the motor vehicle remains stationary during the process, thereby avoiding excessive condensation.

[0025] A third aspect of the invention relates to a motor vehicle, also referred to simply as a vehicle, and preferably designed as a motor car, in particular as a passenger car, which has at least one internal combustion engine according to the first aspect of the invention and can be driven by means of the internal combustion engine. Advantages and advantageous embodiments of the first and second aspects of the invention are to be regarded as advantages and advantageous embodiments of the third aspect of the invention, and vice versa.

[0026] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the single figure alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0027] The drawing shows in the single figure a schematic representation of an internal combustion engine of a motor vehicle, wherein the internal combustion engine can be operated in a targeted heating mode, by means of which air and thus at least a part of an intake tract of the internal combustion engine can be heated in a targeted manner.

[0028] The single figure shows a schematic representation of an internal combustion engine 10 of a motor vehicle, also simply referred to as a vehicle, which can be driven by the internal combustion engine 10. The internal combustion engine 10 has an engine block 12, which is designed as a cylinder block. The engine block 12 forms several cylinders 14 of the internal combustion engine 10. Each cylinder 14 defines a combustion chamber 16 of the internal combustion engine 10, in whose combustion chambers 16 the combustion processes take place during firing operation of the internal combustion engine. The respective combustion chamber 16 is partially defined by the respective cylinder 14 and by a respective piston arranged translationally within the respective cylinder 14. During the respective combustion process, a fuel-air mixture is burned, thereby driving the respective piston.The internal combustion engine 10 has an intake manifold 18 through which air flows, in which an air filter 20, shown schematically in the figure, is arranged. The air flowing through the intake manifold 18 can be filtered by means of the air filter 20. The air flowing through the intake manifold 18 can then be directed to and into the combustion chambers 16 of the internal combustion engine 10.

[0029] The internal combustion engine 10 has an exhaust gas turbocharger 22, which includes a compressor 24 arranged in the intake tract 18, with a compressor wheel 26 also arranged in the intake tract 18. By means of the compressor 24, i.e., by means of the compressor wheel 26, the air flowing through the intake tract 18 can be compressed by driving the compressor 24, i.e., by driving the compressor wheel 26. The air compressed by the compressor 24 is also referred to as charge air. The internal combustion engine 10 has an exhaust tract 28, through which exhaust gas from the internal combustion engine 10 can flow. The exhaust gas originates from the combustion chambers 16 and results from the combustion processes. The exhaust gas turbocharger 22 has a turbine 30 arranged in the exhaust tract 28, with a turbine wheel 32 also arranged in the exhaust tract 28. The turbine wheel 32 and thus the turbine 30 can be driven by the exhaust gas flowing through the exhaust tract 28.In particular, the compressor wheel 26 and thus the compressor 24 can be driven by the turbine wheel 32, i.e. by the turbine 30, via a shaft 35 of the exhaust gas turbocharger 22.

[0030] Turbine 30 is associated with a bypass device 34, which includes a bypass line 36. The bypass line 36 is also referred to as a wastegate line. The bypass device 34 has a bypass valve 38 located in the bypass line 36. By means of the bypass line 36, at least a portion of the exhaust gas flowing through the exhaust tract 28 can be diverted from the exhaust tract 28 at a first branch point A1 and introduced into the bypass line 36. The exhaust gas diverted from the exhaust tract 28 and introduced into the bypass line 36 can be guided by means of the bypass line 36 to a first inlet point E1 and reintroduced into the exhaust tract 28 at the first inlet point E1. The amount of exhaust gas flowing through the bypass line 36 can be adjusted by means of the bypass valve 38, which is also referred to as waste gate or waste gate valve.It can be seen that, in the direction of flow of the exhaust gas flowing through the exhaust tract 28, the branch point A1 is arranged downstream of, in particular all, combustion chambers 16 of the internal combustion engine 10 and upstream of the turbine wheel 32, that is, upstream of the turbine 30. In the direction of flow of the exhaust gas flowing through the exhaust tract 28, the first inlet point E1 is arranged downstream of the turbine wheel 32, that is, downstream of the turbine 30.

[0031] The turbine wheel 32, the compressor wheel 26, and the shaft 35 are, for example, components of a rotating assembly of the exhaust gas turbocharger 22, whose rotating assembly is also referred to as the rotor. The rotating assembly is rotatably mounted on a bearing housing 40 of the exhaust gas turbocharger 22, which is shown particularly schematically in the figure. For example, the compressor 24 has a compressor housing in which the compressor wheel 26 is rotatably arranged. Thus, the compressor housing is open to air flowing through the intake tract 18.

[0032] The internal combustion engine 10 also has a recirculating air system 42, which includes a recirculating air line 44. By means of the recirculating air line 44, at least a portion of the air flowing through the intake tract 18, and in particular the air compressed by the compressor wheel 26, can be diverted from the intake tract 18 at a second branch point A2 and reintroduced into the intake tract 18 at a second inlet point E2. For this purpose, the recirculating air line 44 is fluidically connected to the intake tract 18 at branch point A2 and inlet point E2. Similarly, the bypass line 36 is fluidically connected to the exhaust tract 28 at branch point A1 and inlet point E1.

[0033] In the direction of airflow through the intake tract 18, the inlet point E2 is located upstream of the compressor 24, i.e., upstream of the compressor wheel 26, and downstream of the air filter 20. In the direction of airflow through the intake tract 18, the branch point A2 is located downstream of the compressor 24, i.e., downstream of the compressor wheel 26, and upstream of a throttle valve 46 of the internal combustion engine 10 located in the intake tract 18. The bypass air system 42 also includes a bypass air valve 48, which is located in the bypass air duct 44. The amount of air flowing through the bypass air duct 44 can be adjusted by means of the bypass air valve 48. The internal combustion engine 10 comprises the throttle valve 46, which is arranged downstream of the branch point A2 and upstream of, in particular all, combustion chambers 16 in the direction of flow of the air flowing through the intake tract 18.The throttle valve 46 allows the amount of air to be introduced into the combustion chambers 16, in particular all of them, to be adjusted. In the figure, a section TB of the intake tract 18 is illustrated by a dashed line, and this section TB will be discussed in more detail below.

[0034] To effectively and efficiently prevent undesirable, excessive condensation, at least in the sub-area TB, an electric machine 50 is assigned to the compressor 24, i.e., the compressor wheel 26, so that the internal combustion engine 10 incorporates the electric machine 50. The compressor wheel 26, i.e., the compressor 24, can be driven by the electric machine 50, in particular via the shaft 35. Furthermore, the internal combustion engine 10 can be operated in a controlled heating mode. A method for operating the internal combustion engine 10 is described below, in which the internal combustion engine 10 is operated in a controlled heating mode. In this heating mode, the internal combustion engine 10 is not fired, so that no combustion processes take place in any of the combustion chambers 16, and in particular, in any combustion chamber of the internal combustion engine 10.In the heating mode, the throttle valve 46 is closed, in particular completely. In the heating mode, the bypass valve 48 is open, in particular completely and thus maximally. Furthermore, in the combustion mode, the electric motor 50 drives the compressor wheel 26 and thus the compressor 24, in particular via the shaft 35, whereby the compressor wheel 26, and thus the compressor 24, delivers air, in particular such that the compressor 24 delivers air, in particular from the area surrounding the vehicle, into the intake manifold 18. The air delivered by the compressor 24, that is, by the compressor wheel 26, in the heating mode is also referred to as heating air.In heating mode, the electric machine 50 drives the compressor 24, causing the compressor 24 to pump the heated air, which is specifically heated by the heating process and circulates in a circuit K. This circuit comprises a continuous length L of the intake tract 18, extending from the inlet point E2 to the branch point A2, within which the compressor 24 is located, and the recirculating air line 44, which also extends continuously from the branch point A2 to the inlet point E2. The circulation of the air in or through the circuit K is illustrated in the figure by arrows 52.During the circulation of the heated air, the heated air flows from the inlet point E2 to the branch point A2, passing through the compressor housing, and the circulating heated air flows from the branch point A2 to the inlet point E2, passing through the recirculating air line 44. In this heating operation, the heated air can be heated particularly quickly, and in particular within a few seconds, to a suitably high temperature of, for example, at least substantially 160 degrees. It is evident that the subsection TB of the intake tract 18 comprises at least the circuit K, and thus at least the circuit K can be heated particularly quickly, and in this case within a few seconds, to a suitably high temperature of, for example, at least substantially 160 degrees Celsius by means of the heated air.This prevents excessive condensation, at least in sub-area TB, thereby avoiding any effects that might result from such condensation. This particularly protects compressor 24.

[0035] Preferably, during the heating operation, the bypass valve 48 is fully open, i.e., maximally open. Furthermore, it is preferably provided that during the heating operation, the motor vehicle is not driven by the internal combustion engine 10, and preferably remains stationary during the heating operation, in particular throughout the entire heating operation, and especially continuously and without interruption.

[0036] Reference symbol list

[0037] 10 Internal combustion engine

[0038] 12 Engine block

[0039] 14 cylinders

[0040] 16 Combustion chamber

[0041] 18 Intake tract

[0042] 20 air filters

[0043] 22 exhaust gas turbochargers

[0044] 24 compressors

[0045] 26 compressor wheel

[0046] 28 Exhaust system

[0047] 30 Turbine

[0048] 32 Turbine wheel

[0049] 34 Bypass facility

[0050] 35 wave

[0051] 36 Bypass line

[0052] 38 Bypass valve

[0053] 40 bearing housings

[0054] 42 Recirculating air device

[0055] 44 Recirculating air duct

[0056] 46 Throttle valve

[0057] 48 Recirculating air valve

[0058] 50 electric machine

[0059] 52 Arrow

[0060] A1 first junction

[0061] A2 second junction

[0062] E1 first insertion point

[0063] E2 second insertion point

[0064] K circulatory system

[0065] L Length range

[0066] TB sub-area

Claims

Patent claims 1. Internal combustion engine (10) for a motor vehicle, comprising: - an intake tract (18) through which air can flow, by means of which the air can be introduced into at least one combustion chamber (16) of the internal combustion engine (10); - a compressor (24) arranged in the intake tract (18) for compressing the air flowing through the intake tract (18); - the compressor (24) is part of an exhaust gas turbocharger (22), which has a turbine (30) arranged in an exhaust gas tract (28) of the internal combustion engine (10) and driven by the exhaust gas flowing through the exhaust gas tract (28) of the internal combustion engine (10), by means of which the compressor (24) can be driven; - a recirculating air device (42) comprising: o a recirculating air duct (44) by means of which at least a portion of the air flowing through the intake tract (18) can be diverted from the intake tract (18) at a branch point (A2) arranged downstream of the compressor (24) and introduced into the intake tract (18) at an inlet point (E2) arranged upstream of the compressor (24); and o a recirculating air valve (48) arranged in the recirculating air duct (44) by means of which the quantity of air flowing through the recirculating air duct (44) can be adjusted; and - a throttle valve (46) arranged in the intake tract (18) upstream of the at least one combustion chamber (16) and downstream of the branch point (A2), by means of which a quantity of air to be introduced into the at least one combustion chamber (16) can be adjusted; characterized in that: - an electric machine (50) is associated with the compressor (24), by means of which the compressor (24) can be driven; and - the internal combustion engine (10) can be operated in a controlled heating mode in which the combustion engine (10) is not fired, the throttle valve (46) is closed, the bypass valve (48) is fully open, and the electric motor (50) drives the compressor (24), whereby the compressor (24) supplies air which can be heated to a temperature of at least substantially 160 degrees by means of the heating mode and circulates in a circuit (K) which comprises a length section (L) of the intake tract (18) extending from the inlet (E2) to the branch (A2), in the length section (L) of which the compressor (24) is arranged, and the bypass duct (44) extending from the branch (A2) to the inlet (E2), and the inlet (E2) downstream of an air filter arranged in the intake tract (18). (20) is ordered.

2. Method for operating an internal combustion engine (10) of a motor vehicle, wherein the internal combustion engine (10) has: - an intake tract (18) through which air can flow, by means of which the air can be introduced into at least one combustion chamber (16) of the internal combustion engine (10); - a compressor (24) arranged in the intake tract (18) for compressing the air flowing through the intake tract (18); - the compressor (24) is part of an exhaust gas turbocharger (22), which has a turbine (30) arranged in an exhaust gas tract (28) of the internal combustion engine (10) and driven by the exhaust gas flowing through the exhaust gas tract (28) of the internal combustion engine (10), by means of which the compressor (24) can be driven; - a recirculating air device (42) comprising: o a recirculating air line (44) by means of which at least a portion of the air flowing through the intake tract (18) can be diverted from the intake tract (18) at a branch point (A2) arranged downstream of the compressor (24) and introduced into the intake tract (18) at an inlet point (E2) arranged upstream of the compressor (24); and a recirculating air valve (48) arranged in the recirculating air duct (44), by means of which the quantity of air flowing through the (44) recirculating air duct can be adjusted; and - a throttle valve (46) arranged in the intake tract (18) upstream of the at least one combustion chamber (16) and downstream of the branch point (A2), by means of which a quantity of air to be introduced into the at least one combustion chamber (16) can be adjusted; characterized in that: - an electric machine (50) is associated with the compressor (24), by means of which the compressor (24) can be driven; and - the internal combustion engine (10) is operated in a controlled heating mode in which the combustion engine (10) is not fired, the throttle valve (46) is closed, the bypass valve (48) is fully open, and the electric motor (50) drives the compressor (24), whereby the compressor (24) delivers air which is heated to a temperature of at least substantially 160 degrees by means of the heating mode and circulates in a circuit (K) in the heating mode, which comprises a length section (L) of the intake tract (18) extending from the inlet point (E2) to the branch point (A2), in whose length section (L) the compressor (24) is arranged, and the bypass valve (44) extending from the branch point (A2) to the inlet point (E2), and the inlet point (E2) being located downstream of a valve arranged in the intake tract (18). air filter (20) is arranged.

3. Method according to claim 2, characterized in that during the heating operation, the motor vehicle is not driven by the internal combustion engine (10).

4. Method according to claim 2 or 3, characterized in that the motor vehicle is stationary during the heating operation.

5. Motor vehicle, with an internal combustion engine (10) according to claim 1, wherein the motor vehicle can be driven by means of the internal combustion engine (10).

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