Internal combustion engine

Abstract

The invention relates to an internal combustion engine, preferably a dual-fuel internal combustion engine. The internal combustion engine comprises a charge-air compressor (22), a combustion chamber (50), and a gas fuel supply device (10) for supplying a gaseous fuel, preferably a hydrogen fuel. The gas fuel supply device (10) opens into a charge-air supply connection between the charge-air compressor (22) and the combustion chamber (50). The invention furthermore relates to a vehicle, in particular a watercraft, or a static application having at least one internal combustion engine.

Description

[0001] internal combustion engine

[0002] Description

[0003] The invention relates to an internal combustion engine, preferably a dual-fuel internal combustion engine, and a vehicle, in particular a watercraft, or a stationary application with at least one internal combustion engine.

[0004] Diesel engines are widely used in shipping due to their operational reliability and the high energy content of diesel fuel.

[0005] To achieve CCh reductions, new technologies are also required in shipping, but these are difficult to introduce in the conservative environment.

[0006] Therefore, "alternative propulsion" systems on ships are currently only known in a few isolated cases. Especially when the required travel time is several hours with a corresponding range, there is still no economically viable alternative to the diesel engine. While the use of diesel-like "green fuels" is technically very easy to manage, the fuels are not yet available at competitive prices and in sufficient quantities.

[0007] Electric propulsion systems are unlikely to replace fossil fuels in shipping. The energy required is usually too high and the energy storage densities too low.

[0008] Purely hydrogen-based solutions, such as fuel cells or combustion engines, are considered disruptive in the traditional shipping sector due to a lack of long-term experience. The lack of hydrogen infrastructure also creates high risks for the operation of pure hydrogen propulsion systems on ships. A further problem is the greater space and weight required for tank systems for hydrogen as an energy carrier compared to the widely used diesel fuel. As a result, only smaller quantities of hydrogen can be bunkered on board. This inevitably limits the operating time. This could have fatal consequences in the event of unplanned changes in the mission profile (e.g., extreme weather conditions, route changes, emergency operations such as firefighting or rescue), leading to the consumption of fuel and thus the failure of all propulsion systems.

[0009] Dual-fuel internal combustion engines are known as an "intermediate solution," in which part of the liquid fuel, usually diesel, is replaced by a gaseous fuel such as hydrogen. In addition, such dual-fuel internal combustion engines can be operated exclusively with the liquid fuel. Dual-fuel internal combustion engines therefore offer the possibility of dimensioning large, expensive, and heavy hydrogen tanks to the size required in "normal" conditions. Fuel reserves can be stored in the usual amount in the form of diesel. In the event of faults or when the hydrogen is depleted, full drive power remains available in pure and familiar (and therefore proven) diesel operation.

[0010] Known dual-fuel internal combustion engines are usually based on normal internal combustion engines designed to operate only on liquid fuel, in particular diesel engines, whereby major modifications are necessary to enable operation in dual-fuel mode.

[0011] In addition, dual-fuel combustion engines are continually being developed further in order to achieve the highest possible substitution rate and thus the greatest possible reduction in liquid fuel consumption.

[0012] Accordingly, it is an object of the invention to provide such a solution that at least partially avoids the disadvantages of previous solutions. In particular, it is an object of the invention to provide an improved internal combustion engine, preferably a dual-fuel internal combustion engine, that achieves the highest possible substitution rate and / or that can be manufactured with the least possible modifications to a known internal combustion engine, e.g., a diesel engine.

[0013] The problem is solved by the features of the independent claims. Advantageous further developments are specified in the dependent claims and the description.

[0014] According to a first general aspect of the invention, an internal combustion engine, preferably a dual-fuel internal combustion engine (e.g., a marine dual-fuel engine), is provided. The internal combustion engine comprises a charge air compressor and a combustion chamber.

[0015] The internal combustion engine further comprises a gaseous fuel supply device for supplying a gaseous fuel, preferably a hydrogen fuel.

[0016] The gaseous fuel supply system leads into a (fluidic) charge air supply connection between the charge air compressor and the combustion chamber. If the internal combustion engine is a dual-fuel internal combustion engine, it can be conveniently operated with a liquid fuel, in particular diesel fuel (as in conventional internal combustion engines) or with a mixture of the liquid fuel and the gaseous fuel. During the mixture, part of the normally required liquid fuel is substituted with the gaseous fuel.

[0017] The present disclosure thus provides an internal combustion engine, in particular a dual-fuel internal combustion engine, that achieves the most uniform distribution possible of the gaseous fuel, e.g., hydrogen, across all cylinders of the internal combustion engine. This distribution, which is as uniform as possible, advantageously leads to the highest possible substitution rates.

[0018] Thorough mixing of the gaseous fuel with the charge air is essential to achieve a uniform distribution of hydrogen among all cylinders of the internal combustion engine. This uniform distribution is required to avoid rich mixtures, i.e., an excessively high proportion of gaseous fuel, or lean mixtures, i.e., an insufficient proportion of gaseous fuel, in individual cylinders. Cylinders with a rich mixture are more susceptible to knocking combustion (autoignition), which would require a reduction in the amount of gaseous fuel replacing a quantity of liquid fuel, e.g., diesel. Therefore, uniform mixing is a key aspect to achieve the highest possible substitution rates.

[0019] Furthermore, a technology is provided with which a known internal combustion engine designed solely for operation with a liquid fuel can be converted into an internal combustion engine, in particular a dual-fuel internal combustion engine, with few modifications, i.e., with only minor interventions in the proven drive train. According to the present disclosure, this merely requires the integration of the gaseous fuel supply device. No further modifications to the internal combustion engine, e.g., to the injection system and / or the valves, are necessary.

[0020] According to one embodiment, the internal combustion engine can further comprise a charge air cooler. The gaseous fuel supply device can open into a connecting section of the charge air supply connection between the charge air compressor and the charge air cooler. The charge air compressor and the charge air cooler are expediently fluidly connected by means of the connecting section to supply charge air from the charge air compressor to the charge air cooler. This arrangement advantageously utilizes the turbulent flow in the charge air cooler to achieve the most homogeneous mixing possible of the charge air and the gaseous fuel, without the need for further technical measures or additional components that could lead to a loss of charge air pressure.

[0021] Furthermore, the introduction, particularly injection, of the gaseous fuel into an intake tract upstream of the intercooler leads to improved cooling due to the gaseous fuel acting as a heat conductor, which allows the mixture temperature to be further reduced. Since a low temperature is a key factor in preventing the gaseous fuel from self-ignition with knocking combustion, the cooling rate is another key aspect that can help achieve the highest possible substitution rates.

[0022] It is also possible for the gaseous fuel supply device to open into a (further) connecting section of the charge air supply connection between the charge air cooler and the combustion chamber. The charge air cooler and the combustion chamber are expediently fluidly connected by means of the (further) connecting section for supplying charge air from the charge air cooler to the combustion chamber. The (further) connecting section can be designed as an intake manifold of the internal combustion engine and / or as a section of the intake manifold. The internal combustion engine can comprise the intake manifold.

[0023] In the context of the invention, the charge air supply connection can preferably extend between the charge air compressor and the combustion chamber, in particular between the charge air compressor and the intercooler and / or between the intercooler and the combustion chamber. Alternatively or additionally, in the context of the invention, the charge air supply connection can comprise, for example, a connecting section between the charge air compressor and the intercooler and / or a (further) connecting section between the intercooler and the combustion chamber, in particular, for example, an intake manifold.

[0024] Furthermore, it is also conceivable that the gaseous fuel supply device opens into a component that is arranged in the charge air supply connection between the charge air compressor and the combustion chamber, e.g., into the charge air cooler.

[0025] According to one embodiment, the gaseous fuel supply device can comprise a gas inlet device. The gas inlet device can fluidically connect the gaseous fuel supply device and the charge air supply connection. The gaseous fuel supply device can open into the fluidic connection via the gas inlet device.

[0026] The charge air supply connection can be formed by one or more (charge air) ducts, e.g., charge air pipes, and / or can have one or more (charge air) ducts, e.g., charge air pipes. The charge air supply connection can have several (charge air) ducts, e.g., two, running essentially parallel to one another.

[0027] According to a further embodiment, the gas introduction device can be designed for a substantially uniformly distributed gas introduction, preferably gas injection, into the charge air supply connection. The uniformly distributed gas introduction into the charge air has the advantage of achieving particularly good mixing of the gaseous fuel with the charge air.

[0028] According to one embodiment, the gas introduction device can have at least one charge air passage, which is arranged in the charge air supply connection and / or which forms a section of the charge air supply connection. A cross-section of the at least one charge air passage can correspond to a cross-section of the charge air supply connection. The cross-section of the at least one charge air passage can be substantially circular. The gas introduction device can also be referred to as an injection ring.

[0029] The gas introduction device can be designed as an injection ring (and / or injection ring and / or “injection ring”) and / or have an annular space in order to distribute the gaseous fuel, preferably in the direction of at least one charge air passage.

[0030] According to one embodiment, a plurality of preferably radial gas passages, e.g., bores, can be arranged in a circumferential surface of the at least one charge air passage, preferably evenly distributed in the circumferential direction of the at least one charge air passage. Thus, the gaseous fuel can be supplied in a finely evenly distributed manner to the charge air, which flows through the charge air supply connection and thus also through the at least one charge air passage to the intercooler. The arrangement of the gas passages can advantageously lead to a uniformly distributed gas introduction into the charge air. According to one embodiment, each of the gas passages can each have a gas nozzle, preferably a mixing nozzle. Thus, the gaseous fuel can be supplied to the charge air not only in a uniformly distributed manner, but also, if desired, in a finely distributed manner.

[0031] According to one embodiment, the gas introduction device can have a gas inlet. The gas inlet can be arranged substantially parallel to the at least one charge air passage. The gas introduction device can be fastened, in particular screwed and / or flanged, in the region of the gas inlet to a connection via which the gaseous fuel can be supplied to the gas inlet.

[0032] According to one embodiment, the gas introduction device can have a plurality of charge air passages, preferably arranged in parallel. The gas inlet can be arranged substantially centrally above the plurality of charge air passages. An interior space and / or the annular space of the gas introduction device can be designed to distribute the gaseous fuel admitted via a gas inlet between the plurality of charge air passages. The interior space and / or the annular space can split towards the plurality of charge air passages and preferably each form a gas guide to one of the charge air passages. As a result, the gaseous fuel can advantageously be distributed evenly between the plurality of charge air passages and thus a substantially equal amount of gaseous fuel can be introduced into each of the plurality of charge air passages.

[0033] According to one embodiment, the gaseous fuel supply device may comprise a gaseous fuel metering device for controllably metering the gaseous fuel.

[0034] The gaseous fuel metering device and the gas introduction device, in particular the gas inlet of the gas introduction device, can expediently be fluidically connected to one another. The gaseous fuel metering device and the gas introduction device can be fluidically connected via a connection formed in particular by one or more channels, e.g., pipes. The connection can be double-walled.

[0035] The gaseous fuel metering device can be fluidly connected to a source of the gaseous fuel, preferably a gaseous fuel tank, e.g., via a gas supply connection. The gas supply connection can be formed by one or more channels, e.g., pipes. The gaseous fuel metering device can have a sealed and / or double-walled wall construction. The wall construction can form a cover or housing. The gaseous fuel can be introduced into the gaseous fuel metering device at a gas pressure of less than 10 bar, e.g., 7 bar.

[0036] A double-walled gas supply connection may be provided to supply the gaseous fuel to the gaseous fuel metering device. The gaseous fuel may be introduced into the gaseous fuel metering device via the double-walled gas supply connection, preferably from the gaseous fuel tank. The double-walled connection and the double-walled gas supply connection may be arranged coaxially with each other.

[0037] The double-walled design has the advantage that if an inner wall leaks through which the gaseous fuel escapes, the gaseous fuel can be collected by an outer wall and safely discharged to the outside, e.g. overboard.

[0038] According to one embodiment, intermediate spaces, each formed by an inner wall and an outer wall surrounding the inner wall of the double-walled connection, the double-walled wall construction, and / or the double-walled gas supply connection, can be fluidly connected to one another for discharging the gaseous fuel in the event of a leak. The intermediate spaces can each be designed as an annular volume.

[0039] In other words, the double-walled connection can have a first intermediate space formed by an inner wall and an outer wall surrounding the inner wall, the double-walled wall construction can have a second intermediate space formed by an inner wall and an outer wall surrounding the inner wall, and / or the double-walled gas supply connection can have a third intermediate space formed by an inner wall and an outer wall surrounding the inner wall. The first intermediate space, the second intermediate space, and / or the third intermediate space can be fluidically connected such that the gaseous fuel can be discharged in the event of a leak (in an inner wall).

[0040] Thus, in the event of a leak in one of the inner walls, the gaseous fuel can be advantageously discharged (or vented) to the outside, e.g., overboard, via the gaps. In particular, this protection can be ensured in the event of a leak in the entire gaseous fuel supply system or along the entire gaseous fuel supply line within the gaseous fuel supply system.

[0041] According to one embodiment, the double-walled connection, the double-walled wall construction, and / or the double-walled gas supply connection can have a sensor system for detecting a leak. The sensor system can be arranged in at least one of the intermediate spaces.

[0042] The sensor system can preferably be arranged at an end region of the double-walled gas supply connection facing away from the double-walled wall construction. The sensor system can be connected for signaling purposes to a control device of the internal combustion engine, wherein the control device can be configured to shut off the supply of gaseous fuel to the internal combustion engine in the event of a leak and simultaneously switch to (mono-fuel) operation with the liquid fuel, so that the internal combustion engine remains operable without interruption. Thus, a leak can be advantageously detected by means of the sensor system, for example, when the gaseous fuel flows around it, thus ensuring the safety of the internal combustion engine.

[0043] According to one embodiment, the gaseous fuel metering device can comprise at least one controllable valve, preferably at least one metering valve, for controllably metering the gaseous fuel. The gaseous fuel metering device can comprise a plurality of controllable valves arranged side by side.

[0044] The at least one controllable valve can be controlled, in particular opened and closed, by the control device of the internal combustion engine. The control device can be configured to cause the at least one controllable valve to allow a predetermined amount of gaseous fuel (from a distributor volume) to pass through it for an operating point of the internal combustion engine. The predetermined amount can be stored (e.g., in a memory of the control device) and / or be calculable by the control device.

[0045] According to one embodiment, the gaseous fuel metering device can comprise a distributor volume and a collection volume. The at least one controllable valve can be designed for the controllable metering of the gaseous fuel from the distributor volume into the collection volume. The collection volume can comprise one, preferably single, chamber and / or be designed to combine the gaseous fuel after the controllable metering by the at least one controllable valve. The gaseous fuel metering device can be designed such that the gaseous fuel can pass from the distributor volume into the collection volume exclusively via the at least one controllable valve. In other words, the distributor volume and the collection volume can be fluidly connected to one another, preferably exclusively, via the at least one controllable valve. The distributor volume can be referred to as a rail.

[0046] According to one embodiment, the gaseous fuel supply device can be designed to be fixed to the internal combustion engine, attached to a main component of the internal combustion engine, preferably in a supporting manner, and / or be an integral part of the internal combustion engine. Thus, advantageously, no additional supporting structure is required for the gaseous fuel supply device.

[0047] The internal combustion engine may further comprise at least one cylinder having at least one intake port with an intake valve and / or at least one exhaust port with an exhaust valve for fluidic connection to the combustion chamber of the internal combustion engine, and / or a turbine. The at least one intake port with the intake valve and / or the at least one exhaust port with the exhaust valve may be formed in a cylinder head of the at least one cylinder.

[0048] The internal combustion engine may further comprise an exhaust aftertreatment system. The exhaust aftertreatment system may include a particulate filter and / or an SCR catalyst (e.g., for compliance with the EU Stage V emissions standard).

[0049] The internal combustion engine may comprise an intake tract having the charge air compressor, the charge air cooler, the intake manifold and the at least one intake port with the intake valve (connected in series).

[0050] The internal combustion engine may further comprise an exhaust tract having the at least one exhaust port with the exhaust valve, the turbine and preferably the exhaust gas aftertreatment system (connected in series).

[0051] The charge air cooler can be fluidly connected to the intake manifold, the at least one intake port with the intake valve, and the combustion chamber by means of the charge air supply connection, preferably for supplying a mixture of charge air guided in the charge air supply connection and the gaseous fuel supplied by the gaseous fuel supply device. Alternatively, the fluidic connection of the charge air cooler to the intake manifold, the at least one intake port with the intake valve, and the combustion chamber can be formed at least in sections by the charge air supply connection. The charge air supply connection can expediently be part of the intake tract.

[0052] The at least one exhaust channel with the exhaust valve can be fluidically connected to the turbine and preferably to the exhaust gas aftertreatment system, in particular for discharging an exhaust gas from the combustion chamber and for driving the turbine by the exhaust gas.

[0053] The turbine and the charge air compressor can form a turbocharger.

[0054] The internal combustion engine may have multiple charge air compressors (and thus turbochargers) and multiple charge air coolers. The multiple charge air compressors are expediently arranged upstream of the gas introduction device. In other words, preferably no charge air compressors are arranged between the gas introduction device and the intake manifold.

[0055] The internal combustion engine may further comprise a liquid fuel metering device, in particular a (common rail) injection system. A liquid fuel, in particular diesel, may be introduced into a combustion chamber via controllable injectors of the injection system. The injectors may be controllable, in particular openable and closable, by means of the control device of the internal combustion engine. The control device may be designed to cause the injectors to introduce a quantity of liquid fuel predetermined for an operating point of the internal combustion engine into the combustion chamber. Furthermore, a metering start time (i.e., an injection time) and / or a metering pressure of the liquid fuel (i.e., a rail pressure) may be adjustable and / or controllable.The predetermined metered quantity of liquid fuel can depend on the predetermined metered quantity of gaseous fuel that is passed through the at least one controllable valve of the gaseous fuel metering device (and vice versa). Thus, a precisely metered, reduced metered quantity of, for example, diesel fuel can enter the combustion chamber and ignite a cylinder charge, wherein the metered quantity, the metering start time, and / or the metering pressure can be advantageously adapted and optimized for combustion.

[0056] The internal combustion engine can be operated with a liquid fuel, preferably a diesel fuel, and / or the gaseous fuel, preferably a hydrogen fuel.

[0057] The internal combustion engine may be a dual-fuel internal combustion engine which is operable, preferably selectively, in a mono-fuel mode with a liquid fuel, preferably a diesel fuel, or in a dual-fuel mode with the liquid fuel and the gaseous fuel, preferably a hydrogen fuel.

[0058] The internal combustion engine may include the control device. Alternatively, the control device may be part of a vehicle or stationary application (i.e., the vehicle or stationary application may include the control device).

[0059] The control device may comprise a liquid fuel control unit for regulating and / or controlling a dosage of the liquid fuel in mono-fuel mode and / or dual-fuel mode, and a gaseous fuel control unit for regulating and / or controlling a dosage of the gaseous fuel in dual-fuel mode.

[0060] The gaseous fuel control unit may further be configured to regulate and / or control a metering of the gaseous fuel in a mode in which the internal combustion engine is operated solely with the gaseous fuel (and not with the liquid fuel).

[0061] The liquid fuel control unit can be designed to repeatedly check whether at least one switching condition for switching between the mono-fuel mode and the dual-fuel mode is met, and preferably to initiate the switching when the at least one switching condition is met.

[0062] The at least one switching condition for switching from the mono-fuel mode to the dual-fuel mode can include exceeding and / or falling below the threshold value of at least one predetermined threshold value of at least one physical variable of the dual-fuel internal combustion engine, preferably a pressure and / or a temperature, faultless operation of the liquid fuel control unit and / or faultless operation of the gaseous fuel control unit.

[0063] A switchover from mono-fuel mode to dual-fuel mode can be initiated by the following sequence if at least one switchover condition is met: a) Sending of an enable message by the liquid fuel control unit to the gaseous fuel control unit that switching to dual-fuel mode is permitted, b) Sending of a request message, preferably in response to the enable message, by the gaseous fuel control unit to the liquid fuel control unit to request a switchover from mono-fuel mode to dual-fuel mode, and c) Sending of a feedback message, preferably in response to the request message, by the liquid fuel control unit to the gaseous fuel control unit that a switchover from mono-fuel mode to dual-fuel mode is initiated.

[0064] The liquid fuel control unit can be designed to perform a check of a data content of the request message by means of a checksum check for integrity and by means of a rolling counter for timeliness, and to send the feedback message if the check is successful.

[0065] The gas fuel control unit can be designed to check at least one gas fuel-specific switching condition and / or a content of the release message and to send the request message if the at least one gas fuel-specific switching condition is met and / or the content of the release message meets at least one predetermined criterion.

[0066] The liquid fuel control unit and / or the gas fuel control unit can be designed to initiate a switchover from the dual-fuel mode to the mono-fuel mode if and / or as soon as at least one of the following switchover conditions exists: a faulty and / or interrupted communication connection between the liquid fuel control unit and the gas fuel control unit, faulty operation of the liquid fuel control unit, faulty operation of the gas fuel control unit, a limit value violation of at least one predetermined limit value of at least one physical variable of the dual-fuel internal combustion engine, preferably a pressure and / or a temperature, e.g.a boost pressure of a charge air below a predetermined limit boost pressure and / or a pressure in a gaseous fuel metering device outside a predetermined pressure range, an insufficient amount of gaseous fuel in a gaseous fuel tank, a leak through which the gaseous fuel escapes, and / or a faulty sensor for detecting a leak through which the gaseous fuel escapes.

[0067] The switchover from dual-fuel mode to mono-fuel mode can be initiated by a) a withdrawal of at least one of the release message, the request message and / or the feedback message, preferably directly and / or without a further message, b) a sequence identical to the sequence for switching from mono-fuel mode to dual-fuel mode, and / or c) a withdrawal of the release message, the request message and the feedback message in a sequence different from the sequence for switching from mono-fuel mode to dual-fuel mode.

[0068] A speed and / or torque of the internal combustion engine can be regulated and / or controlled by the liquid fuel control unit in mono-fuel mode and dual-fuel mode. The liquid fuel control unit can be configured to determine a target torque for operating the internal combustion engine in mono-fuel mode and dual-fuel mode for a predetermined target speed and / or a predetermined pedal value.

[0069] The liquid fuel control unit can be connected by signaling to the liquid fuel metering device of the internal combustion engine, preferably a common rail injection system, for metering the liquid fuel.

[0070] The gas fuel control unit can be connected to the gas fuel metering device of the internal combustion engine for metering the gaseous fuel.

[0071] The liquid fuel control unit can be designed to regulate and / or control at least one parameter of the liquid fuel metering device, preferably wherein the at least one parameter comprises at least a metering start time, a metering duration, a metering pressure, a metering number and / or a metered quantity of the liquid fuel to be metered.

[0072] The gaseous fuel control unit can be designed to regulate and / or control at least one parameter of the gaseous fuel metering device, preferably wherein the at least one parameter comprises at least a metering start time, a metering duration, a metering pressure, a metering number and / or a metered quantity of the gaseous fuel to be metered.

[0073] The at least one parameter of the liquid fuel metering device can be determined, regulated and / or controlled by the liquid fuel control unit as a function of at least one stored characteristic map dependent on an operating point of the internal combustion engine and preferably an actual rotational speed, an actual torque and / or an actual metered quantity.

[0074] The at least one stored characteristic map can comprise at least one characteristic map for the mono-fuel mode and at least one characteristic map for the dual-fuel mode.

[0075] When switching between mono-fuel mode and dual-fuel mode, switching can occur between the at least one characteristic map for mono-fuel mode and the at least one characteristic map for dual-fuel mode for determining the at least one parameter. The at least one parameter can be switched successively, preferably along a transition curve.

[0076] The liquid fuel control unit can be designed to regulate and / or control the at least one parameter of the liquid fuel metering device in order to increase or limit heat emission of the metered, gaseous fuel during combustion of the metered, liquid fuel and the metered, gaseous fuel to achieve a predetermined target speed and / or a target torque in dual-fuel mode, so that a smaller amount of nitrogen oxide is produced during combustion than in mono-fuel mode and / or knocking combustion is avoided.

[0077] The gaseous fuel control unit can be configured to regulate and / or control the at least one parameter of the gaseous fuel metering device in dual-fuel mode as a function of an operating point of the internal combustion engine. Preferably, the gaseous fuel control unit can also be configured to receive a message containing the operating point from the liquid fuel control unit.

[0078] The control device can also be designed to detect a leak through which the gaseous fuel escapes.

[0079] The control device can be signal-connected to the sensor system for detecting the leak. Preferably, a leak can be detected if a detected leakage gas mass flow is above a threshold. The threshold can be, for example, between 40 g / min and 60 g / min, in particular 48 g / min.

[0080] Alternatively or additionally, a leak can be detected if the pressure in a gaseous fuel metering device is below a predetermined pressure threshold. Leak detection can be performed for the internal combustion engine both during operation and when the internal combustion engine is shut down.

[0081] It is also conceivable that the internal combustion engine could be used not only as a prime mover, but also for a motor-generator arrangement (“marine genset”) to provide a combination of a drive, in particular a dual-fuel drive, and an electric drive.

[0082] According to a further general aspect of the invention, a vehicle, in particular a watercraft, or a stationary application with at least one internal combustion engine as disclosed herein is provided.

[0083] The previously described embodiments, variants, and features of the invention can be combined with one another as desired. Further details and advantages of the invention are described below with reference to the accompanying drawings. They show:

[0084] Figure 1 is a schematic view of a section of an internal combustion engine according to an embodiment of the present disclosure; and

[0085] Figure 2 is a schematic view of a gas introduction device for an internal combustion engine according to an embodiment of the present disclosure.

[0086] Figure 1 schematically shows a section of an internal combustion engine, preferably a dual-fuel internal combustion engine. The internal combustion engine comprises a charge air compressor 22, a combustion chamber 50, and a gaseous fuel supply device 10 for supplying a gaseous fuel, preferably a hydrogen fuel.

[0087] Furthermore, the internal combustion engine may have the usual structure of an internal combustion engine, e.g., an intake tract 20 having the charge air compressor 22, a charge air cooler 26, and an intake manifold 28 connected in series. The charge air compressor 22 may be part of a turbocharger, with a turbine 42 of the turbocharger being arranged in an exhaust tract 40 of the internal combustion engine.

[0088] The gaseous fuel supply device 10 opens into a charge air supply connection between the charge air compressor 22 and the combustion chamber 50. For this purpose, the gaseous fuel supply device 10 can, in particular, comprise a gas inlet device 18, via which the gaseous fuel supply device 10 opens into the charge air supply connection. The gaseous fuel supply device 10 can preferably open into a connecting section 24 of the charge air supply connection between the charge air compressor 22 and the charge air cooler 26.

[0089] Furthermore, it is also possible for the gaseous fuel supply device 10 to open into a charge air supply section of the charge air supply connection between the charge air cooler 26 and the combustion chamber 50, e.g., into the intake manifold 28.

[0090] A quantity of gaseous fuel, e.g., a hydrogen stream, can thus be introduced into the charge air supply connection by means of the gaseous fuel supply device 10, where the gaseous fuel is mixed with the charge air. This mixture of charge air and the gaseous fuel, e.g., a charge air-hydrogen mixture, can then flow into the charge air cooler 26, the intake manifold 28, and finally into at least one intake port with an intake valve 32 in at least one cylinder 30. After a combustion process, an exhaust gas generated thereby can flow out of the at least one cylinder 30 through at least one exhaust port with an exhaust valve 34 and drive the turbine 42 of the turbocharger 40, which in turn can drive the charge air compressor 22 of the turbocharger to maintain a boost pressure of the charge air.

[0091] The gaseous fuel supply device 10 may comprise a gaseous fuel metering device 14 for controllably metering the gaseous fuel. The gaseous fuel metering device 14 may comprise at least one controllable valve 14-2, preferably at least one metering valve, for controllably metering the gaseous fuel.

[0092] The gaseous fuel metering device 14 can comprise a distribution volume 14-1 and a collection volume 14-3. The distribution volume 14-1 and the collection volume 14-3 can be fluidically connected exclusively via the at least one controllable valve 14-2. Accordingly, the at least one controllable valve 14-2 can be configured for the controllable metering of the gaseous fuel from the distribution volume 14-1 into the collection volume 14-3.

[0093] If the gaseous fuel supply device 10 comprises the gas inlet device 18 and the gaseous fuel metering device 14, the gas inlet device 18 and the gaseous fuel metering device 14 are expediently fluidically connected, in particular via a double-walled connection 16. Furthermore, the gaseous fuel metering device 14 can have a double-walled wall construction. Furthermore, a double-walled gas supply connection 12 can be provided to supply the gaseous fuel to the gaseous fuel metering device 14.

[0094] Intermediate spaces, each formed by an inner wall and an outer wall surrounding the inner wall of the double-walled connection 16, the double-walled wall structure of the gaseous fuel metering device 14, and / or the double-walled gas supply connection 12, can be fluidically connected to one another to discharge the gaseous fuel in the event of a leak. To detect a leak, the double-walled connection 16, the double-walled wall structure of the gaseous fuel metering device 14, and / or the double-walled gas supply connection 12 can further comprise a sensor system 60. The sensor system 60 can preferably be arranged at an end region of the double-walled gas supply connection 12 facing away from the double-walled wall structure.

[0095] Figure 2 shows the gas introduction device 18 according to an embodiment, wherein the gas introduction device 18 can be designed in particular for substantially uniformly distributed gas introduction, preferably gas injection, into the charge air supply connection, in particular the connecting section 24.

[0096] The gas introduction device 18 can have a gas inlet 18-1, which can in particular be arranged substantially parallel to the at least one charge air passage 18-4.

[0097] The gas introduction device 18 may have at least one charge air passage 18-4 which is arranged in the charge air supply connection and / or which forms a section of the charge air supply connection.

[0098] The gas introduction device 18 can be designed as an injection ring (and / or injection ring and / or “injection ring”) and / or have an interior space and / or annular space 18-2 in order to distribute the gaseous fuel, preferably in the direction of the at least one charge air passage 18-4.

[0099] The gas introduction device 18 can also have a plurality of charge air passages 18-4, preferably arranged in parallel, e.g., two charge air passages 18-4. The interior and / or annular space 18-2 of the gas introduction device 18 can be configured to distribute the gaseous fuel admitted via the gas inlet 18-1 among the plurality of charge air passages 18-4.

[0100] A plurality of gas passages 18-3 can be arranged in a circumferential surface of the at least one charge air passage 18-4, preferably evenly distributed in the circumferential direction of the at least one charge air passage 18-4. Furthermore, each of the gas passages 18-3 can have a gas nozzle.

[0101] The invention is not limited to the preferred embodiments described above. Rather, a multitude of variants and modifications are possible, which also utilize the inventive concept and therefore fall within the scope of protection. In particular, the invention also claims protection for the subject matter and features of the subclaims, independently of the claims referred to. In particular, the individual features of the independent claims are each disclosed independently of one another. In addition, the features of the subclaims are also disclosed independently of all features of the independent claims.

[0102] List of reference symbols

[0103] 10 Gas fuel supply device

[0104] 12 double-walled gas supply connection

[0105] 14 Gas fuel metering device

[0106] 14-1 Distribution volume

[0107] 14-2 controllable valve

[0108] 14-3 Collection volume

[0109] 16 double-walled connection

[0110] 18 Gas introduction device

[0111] 18-1 Gas inlet

[0112] 18-2 Interior, annular space

[0113] 18-3 Gas passages

[0114] 18-4 Charge air passage

[0115] 20 Intake tract

[0116] 22 charge air compressors

[0117] 24 Connecting section of the charge air supply connection

[0118] 26 intercooler

[0119] 28 intake manifold

[0120] 30 cylinders

[0121] 32 intake ports with one intake valve

[0122] 34 exhaust port with one exhaust valve

[0123] 40 Exhaust system

[0124] 42 turbines

[0125] 50 combustion chamber

[0126] 60 sensors to detect a leak

Claims

Patent claims 1. Internal combustion engine, preferably a dual-fuel internal combustion engine, comprising: a charge air compressor (22); a combustion chamber (50); and a gas fuel supply device (10) for supplying a gaseous fuel, preferably a hydrogen fuel, characterized in that the gas fuel supply device (10) opens into a charge air supply connection between the charge air compressor (22) and the combustion chamber (50).

2. Internal combustion engine according to claim 1, wherein the internal combustion engine further comprises an intercooler (26), and a) the gas fuel supply device (10) opens into a connecting section (24) of the charge air supply connection between the charge air compressor (22) and the charge air cooler (26), and / or b) the gas fuel supply device (10) opens into a connecting section of the charge air supply connection between the charge air cooler (26) and the combustion chamber (50), preferably wherein the connecting section is designed as an inlet manifold (28) of the internal combustion engine.

3. Internal combustion engine according to claim 1 or 2, wherein the gas fuel supply device (10) comprises a gas inlet device (18) which fluidically connects the gas fuel supply device (10) and the charge air supply connection.

4. Internal combustion engine according to claim 3, wherein a) the gas introduction device (18) is designed for substantially uniform gas introduction, preferably gas injection, into the charge air supply connection, and / or b) the gas introduction device (18) is designed as an injection ring and / or has an annular space (18-2) to divide the gaseous fuel, preferably in the direction of at least one charge air passage (18-4).

5. Internal combustion engine according to claim 3 or 4, wherein the gas inlet device (18) has at least one charge air passage (18-4) which is arranged in the charge air supply connection and / or which forms a section of the charge air supply connection.

6. Internal combustion engine according to claim 5, wherein several, preferably radial, gas passages (18-3) are arranged in a circumferential surface of the at least one charge air passage (18-4), preferably evenly distributed in the circumferential direction of the at least one charge air passage (18-4).

7. Internal combustion engine according to claim 6, wherein each of the gas passages (18-3) has a gas nozzle, preferably a mixing nozzle.

8. Internal combustion engine according to one of claims 5 to 7, wherein the gas inlet device (18) has several, preferably parallel, charge air passages (18-4), preferably wherein an interior space and / or annular space (18-2) of the gas inlet device (18) is formed to divide the gaseous fuel admitted via a gas inlet (18-1) to the several charge air passages (18-4).

9. Internal combustion engine according to one of the preceding claims, wherein the gas fuel supply device (10) comprises a gas fuel metering device (14) for controllable metering of the gaseous fuel.

10. Internal combustion engine according to claim 9, wherein the gas fuel metering device (14) and the gas inlet device (18) are fluidically connected via a double-walled connection (16), and / or the gas fuel metering device (14) has a double-walled wall construction, and / or a double-walled gas supply connection (12) is provided to supply the gaseous fuel to the gas fuel metering device (14).

11. Internal combustion engine according to claim 10, wherein the spaces formed by an inner wall and an outer wall surrounding the inner wall of the double-walled connection (16), the double-walled wall construction of the gas fuel metering device (14) and / or the double-walled gas supply connection (12) are fluidically connected to each other for the purpose of discharging the gaseous fuel in the event of a leak.

12. Internal combustion engine according to claim 10 or 11, wherein the double-walled connection (16), the double-walled wall construction of the gas fuel metering device (14) and / or the double-walled gas supply connection (12) incorporates a sensor for detecting exhibit a leakage, preferably wherein the sensor is arranged at an end area of ​​the double-walled gas supply connection (12) facing away from the double-walled wall construction.

13. Internal combustion engine according to one of claims 9 to 12, wherein the gas fuel metering device (14) comprises at least one controllable valve (14-2), preferably at least one metering valve, for controllable metering of the gaseous fuel.

14. Internal combustion engine according to claim 13, wherein the gas fuel metering device (14) comprises a distribution volume (14-1) and a collection volume (14-3), and the at least one controllable valve (14-2) is designed for controllable metering of the gaseous fuel from the distribution volume (14-1) into the collection volume (14-3).

15. Internal combustion engine according to one of the preceding claims, wherein the gas fuel supply device (10) is permanently attached to the internal combustion engine, is attached to a main component of the dual-fuel internal combustion engine, preferably in a load-bearing manner, and / or is an integral part of the internal combustion engine.

16. Internal combustion engine according to one of the preceding claims, further comprising: an inlet manifold (28); at least one cylinder having at least one inlet port with an inlet valve (32) and / or at least one outlet port with an outlet valve (34) for fluidic connection with the combustion chamber (50); a turbine (42);and / or an exhaust aftertreatment system, preferably wherein a) the charge air cooler (26) is fluidically connected to the intake manifold (28), the at least one intake port (32) and the combustion chamber (50) by means of the charge air supply connection, preferably for supplying a mixture of charge air guided in the charge air supply connection and the gaseous fuel supplied by the gas fuel supply device (10) into the combustion chamber (50), and / or b) the at least one outlet port (34) is fluidically connected to the turbine (42) and preferably to the exhaust aftertreatment system, in particular for removing exhaust gas from the combustion chamber (50) and for driving the turbine (42) by the exhaust gas, and / or c) the turbine (42) and the charge air compressor (22) form a turbocharger.

17. Internal combustion engine according to one of the preceding claims, wherein a) the internal combustion engine is operable with a liquid fuel, preferably a diesel fuel, and / or the gaseous fuel, and / or b) the internal combustion engine is a dual-fuel internal combustion engine that is operable in a mono-fuel mode with a liquid fuel, preferably a diesel fuel, or in a dual-fuel mode with the liquid fuel and the gaseous fuel.

18. Internal combustion engine according to claim 17, wherein the internal combustion engine further comprises a control device, the control device comprising: a liquid fuel control unit for controlling a metering of the liquid fuel in mono-fuel mode and / or dual-fuel mode, and a gas fuel control unit for controlling a metering of the gaseous fuel in dual-fuel mode, wherein the liquid fuel control unit is configured to repeatedly check whether at least one switching condition for switching between the mono-fuel mode and the dual-fuel mode is met, and preferably to initiate the switching when the at least one switching condition is met.

19. Internal combustion engine according to claim 18, wherein the at least one switching condition for switching from mono-fuel mode to dual-fuel mode comprises exceeding and / or falling below a threshold of at least a predetermined threshold of at least one physical quantity of the dual-fuel internal combustion engine, preferably a pressure and / or a temperature, faultless operation of the liquid fuel control unit and / or faultless operation of the gas fuel control unit.

20. Internal combustion engine according to claim 18 or 19, wherein a switchover from mono-fuel mode to dual-fuel mode can be initiated by the following sequence when at least one switchover condition is met: a) sending a release message from the liquid fuel control unit to the gas fuel control unit, indicating that switching to dual-fuel mode is permitted, b) sending a request message, preferably in response to the release message, from the gas fuel control unit to the liquid fuel control unit to request a switchover from mono-fuel mode to dual-fuel mode, and c) Sending a feedback message, preferably in response to the request message, from the liquid fuel control unit to the gas fuel control unit, indicating that a switch from mono-fuel mode to dual-fuel mode is being initiated. Vehicle, in particular a watercraft, or stationary application with at least one internal combustion engine according to one of the preceding claims.

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