Method for absorbing hydrogen in a crankcase of a hydrogen combustion engine, system for a motor vehicle and motor vehicle

Abstract

The present invention provides a method for absorbing hydrogen (H) in a crankcase (14) of a hydrogen internal combustion engine (10), comprising injecting (S1) hydrogen (H) into a combustion chamber (12) of the hydrogen internal combustion engine (10) by a hydrogen injector (11); wherein a piston (13) of the hydrogen internal combustion engine (10) is configured to compress and expand the hydrogen (H) injected into the combustion chamber (12); injecting (S2) a hydrogen carrier medium (L) into the crankcase (14) through a nozzle (15) for hydrogenating the carrier medium (L) within the crankcase (14) with hydrogen (H) escaping from the combustion chamber (12) past a side wall (13a) of the piston (13) into the crankcase (14); collecting (S3) the hydrogenated carrier medium (21) from the crankcase (14) by a collector (20);Heating (S4) the hydrogenated carrier medium (21) by means of a heating device (30) to dehydrogenate the carrier medium (L, 21) and extract hydrogen (H) from the hydrogenated carrier medium (L, 21); and injecting (S5) the dehydrogenated carrier medium (L, 22) through the nozzle (15) into the crankcase (14) for hydrogenation. The present invention further provides a system (1) for a motor vehicle and a motor vehicle (100) having the system (1) according to the invention.

Description

Technical field

[0001] The present invention relates to a method for absorbing hydrogen in a crankcase of a hydrogen combustion engine, a system for a motor vehicle and a motor vehicle with the system according to the invention. background

[0002] In hydrogen internal combustion engines (ICEs), part of the hydrogen-air mixture passes the piston rings into the crankcase during the compression and expansion strokes. This blow-by gas contains hydrogen (H 2 ) and oxygen (O 2 ). The concentration of hydrogen and oxygen can easily reach a critical value, leading to a sudden exothermic reaction, i.e. an explosion, between hydrogen and oxygen, releasing a lot of energy and potentially damaging the engine.

[0003] Document US 10,309,290 B2 describes a cooling cavity in a piston of an internal combustion engine. Two cooling nozzles are designed to spray cooling oil onto the back of the piston and into the cooling cavity. Disclosure of the invention

[0004] The problem of the present invention is to reduce the hydrogen content in the crankcase to prevent the above-mentioned reaction.

[0005] To this end, the present invention provides a method according to claim 1, a system according to claim 15 and a motor vehicle according to claim 23.

[0006] According to one aspect of the invention, a method for absorbing hydrogen in a crankcase of a hydrogen internal combustion engine is provided.The method comprises injecting, by a hydrogen injector, hydrogen into a combustion chamber of the hydrogen internal combustion engine; wherein a piston of the hydrogen internal combustion engine is configured to compress and expand the hydrogen injected into the combustion chamber; injecting, through a nozzle, a hydrogen carrier medium into the crankcase for hydrogenating the carrier medium within the crankcase with hydrogen escaping from the combustion chamber past a side wall of the piston into the crankcase; collecting, by a collector, the hydrogenated carrier medium from the crankcase; heating, by a heater, the hydrogenated carrier medium for dehydrogenating the carrier medium and extracting hydrogen from the hydrogenated carrier medium; and injecting, through the nozzle, the dehydrogenated carrier medium into the crankcase for hydrogenation.

[0007] According to a further aspect of the invention, a system for a motor vehicle is provided. The system comprises a hydrogen internal combustion engine having a combustion chamber, a hydrogen injector for injecting hydrogen into the combustion chamber, a piston for compressing and expanding the hydrogen injected into the combustion chamber, a crankcase arranged on an underside of the piston opposite the combustion chamber, and a nozzle for injecting a hydrogen carrier medium into the crankcase to hydrogenate the carrier medium within the crankcase with hydrogen escaping from the combustion chamber past the sidewalls of the piston into the crankcase; a collector for collecting the hydrogenated carrier medium from the crankcase;and a heating device connected to the collector and configured to heat the carrier medium to obtain a dehydrated carrier medium, wherein the nozzle is configured to inject the dehydrated carrier medium into the crankcase;

[0008] According to a further aspect of the invention, a motor vehicle is provided which comprises the system for a motor vehicle according to the invention.

[0009] One idea of ​​the present invention is to add a hydrogen carrier medium, in particular a liquid organic hydrogen carrier (LOHC), to the oil. The carrier medium can be added by injection, preferably spraying, through a nozzle into the crankcase. The nozzle can preferably be designed as any suitable form of injector that can inject or spray the carrier medium into the crankcase. The carrier medium then absorbs the hydrogen from the blow-by gas in an exothermic reaction. In the case of LOHC, the product of this hydrogenation reaction is hydrogen-saturated LOHC, i.e., [LOHC+H2].

[0010] LOHCs are organic liquids that can absorb and release hydrogen through chemical reactions. Therefore, LOHCs can be used for the safe storage and transport of hydrogen. The absorption of hydrogen, hydrogenation, is an exothermic reaction, while dehydrogenation requires an energy input and is therefore an endothermic reaction. Typical LOHCs are toluene / methylcyclohexane (C7H8 / C7H14), dibenzyltoluene (C21H20), or benzyltoluene (C14H14). Depending on the liquid, up to 56 kg of hydrogen can be stored in 1m 3 LOHC can be transported.

[0011] The carrier medium is then collected by a collector in or near the crankcase and directed to a heater, where the endothermic dehydrogenation reaction takes place to produce unsaturated LOHC and hydrogen from the saturated LOHC. The unsaturated LOHC can then be reused to absorb additional hydrogen in the crankcase. Thus, the hydrogen stored in the LOHC can be released in this endothermic reaction and returned to the combustion process continuously or at specified intervals. The extracted hydrogen cannot return to the crankcase.

[0012] By performing the described process continuously or at appropriate intervals, the hydrogen concentration in the crankcase can be kept low, e.g., below 4% (vol.), even during engine operation. In the resulting chemical composition in the crankcase, an exothermic reaction (explosion) of hydrogen with oxygen is thus no longer possible.

[0013] It is understood that the term "vehicle" or "vehicle" or a similar term as used herein encompasses motor vehicles in general, such as passenger cars, including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, and the like, as well as hydrogen-burning vehicles. It is further understood that the present invention can also be applied to systems with stationary engines and hydrogen combustion engines.

[0014] Advantageous embodiments and improvements of the present invention are contained in the subordinate claims.

[0015] According to one embodiment of the invention, the hydrogen carrier medium is injected, preferably sprayed, into the crankcase in a mixture with a lubricant. In this way, the carrier medium can be injected together with lubricating oil through the same nozzle. Further considerations regarding the suitability of the carrier medium as a lubricant are not necessary. This embodiment thus represents a simple and cost-effective way to inject the carrier medium into the crankcase.

[0016] According to one embodiment of the invention, the hydrogen carrier medium is designed as a lubricant and is injected into the crankcase without any additional lubricant. In this case, the carrier medium replaces the lubricating oil. This allows only one fluid to be used for dehydration and lubrication, simplifying the system.

[0017] According to one embodiment of the invention, the nozzle is designed as a piston cooling nozzle. The nozzle can also be designed as a piston cooling injector. The injector or nozzle is arranged on an underside of the piston opposite the combustion chamber. Typically, such a piston cooling nozzle or injector blows a lubricant jet toward the underside of the piston in a direction parallel to the piston movement, thereby moving the piston to compress and expand the air-fuel mixture in the combustion chamber. When using the same injector type, no additional injector for the carrier medium is required.

[0018] According to one embodiment of the invention, the hydrogenation of the carrier medium involves the use of a catalyst. The presence of the catalyst significantly facilitates the initiation of the exothermic hydrogenation reaction. This allows the carrier medium to be reused almost indefinitely. Furthermore, the heat generated by the exothermic reaction can assist a vehicle during warm-up.

[0019] The heat can then be dissipated through an engine cooling system or engine cooling circuit, which is regularly present in a motor vehicle.

[0020] According to one embodiment of the invention, the catalyst comprises or consists of at least one of the elements nickel, palladium, or platinum. In this way, a known and efficient reaction can be initiated.

[0021] According to one embodiment of the invention, the catalyst is formed as a coating on a rear or underside of a piston and / or on a cylinder liner of a cylinder of the hydrogen internal combustion engine. The piston is located in the cylinder. A hydrogen internal combustion engine may have a plurality of such cylinders, e.g., 3, 4, 6, 8, etc. The rear or underside of the piston is the side facing the crankcase, i.e., opposite a front or top side of the piston facing the combustion chamber. The underside of the piston and the cylinder liner on the cylinder wall are suitable locations for the catalyst to support the hydrogenation reaction.

[0022] According to one embodiment of the invention, the coating is formed as a foam. This increases the surface area of ​​the coating, allowing more catalytic material to support the hydrogenation reaction. In addition to the foam, other surface structures are conceivable, such as ribs or simply a rough profile with grooves and elevations.

[0023] According to one embodiment of the invention, the collector comprises an oil pan. The oil pan is preferably arranged on an underside of the crankcase opposite the combustion chamber. In this way, a simple collector is provided. A pump is configured to suck the hydrogenated carrier medium from the oil pan to the heating device. Furthermore, the oil pan can also collect dehydrated carrier medium that has been returned to the oil pan from the heating device. In this case, the oil pan contains a mixture of hydrogenated and dehydrated carrier medium. An additional oil pump can be configured to suck or pump hydrogenated carrier medium from the oil pan to the nozzle. This oil pump preferably sucks the carrier medium from a location in the oil pan where predominantly dehydrated carrier medium accumulates.

[0024] According to one embodiment of the invention, the heating device is designed as a heat exchanger. The heating device is thus configured to transfer heat from another heated medium to the carrier medium. The method further comprises supplying an exhaust gas to the heat exchanger to heat the hydrogenated carrier medium. In this way, the heat generated by the combustion engine can be reused to heat the carrier medium for dehydrogenation.

[0025] According to one embodiment of the invention, the exhaust gas is supplied from a turbocharger connected to the hydrogen combustion engine and the heat exchanger. In this way, heat from the hydrogen combustion engine can be supplied to the heat exchanger very efficiently. A three-way catalyst can be connected between the turbocharger and the heat exchanger to purify the exhaust gas.

[0026] According to one embodiment of the invention, the method further comprises cooling the carrier medium with a cooler after dehydration of the carrier medium. In this way, the dehydrated carrier medium can be quickly reused, thereby improving the efficiency of the method.

[0027] According to one embodiment of the invention, the cooler is designed as a heat exchanger and connected to an engine cooling circuit used to cool the hydrogen combustion engine. Therefore, no additional cooling circuit is required to dissipate the heat of the carrier medium from the cooler. This allows the cooler to be well integrated into the architecture of the engine or motor vehicle.

[0028] According to one embodiment of the invention, the method further comprises injecting, through the hydrogen injector, the hydrogen extracted from the carrier medium into the combustion chamber of the hydrogen combustion engine. The injection of the extracted hydrogen may also be a manifold injection. In this way, the extracted hydrogen can be reused for the combustion process in the combustion chamber, resulting in a more efficient hydrogen combustion engine.

[0029] According to one embodiment of the invention, the method further comprises detecting, by a sensor, a hydrogen concentration in the crankcase. The sensor can be any type of sensor, such as an electrochemical gas detector, an infrared point sensor, a photoionization detector, or other common types of gas sensors suitable for this task. According to this embodiment, the method further comprises controlling, by a control device, the amount of carrier medium injected into the crankcase based on the detected concentration of hydrogen in the crankcase and / or based on the detected saturation level of the carrier medium. For this purpose, the control device can directly control the nozzle or a valve designed to regulate the amount of carrier medium to be injected into the crankcase by the nozzle.

[0030] According to one embodiment of the invention, the system further comprises a pump connected to the collector and the heating device. The pump is configured to pump the carrier medium from the collector to the heating device. This simplifies the transport of the carrier medium from the collector to the heating device.

[0031] According to one embodiment of the invention, the system further comprises a cooler connected to the heating device. The cooler is configured to cool the dehydrated carrier medium before the cooled and dehydrated carrier medium is re-injected into the crankcase. As already mentioned, this allows the dehydrated carrier medium to be quickly reused, thereby improving the efficiency of the process.

[0032] According to one embodiment of the invention, the cooler is connected to an engine cooling circuit designed to cool the hydrogen combustion engine. As already mentioned, no additional cooling circuit is required to dissipate the heat of the carrier medium from the cooler. This allows the cooler to be easily integrated into the architecture of the motor vehicle.

[0033] According to one embodiment of the invention, the system further comprises a turbocharger connected to the hydrogen combustion chamber and the heating device, so that the heating device is heated by exhaust gas from the turbocharger. In this way, heat from the hydrogen combustion engine can be supplied to the heat exchanger very efficiently. A three-way catalyst can be connected between the turbocharger and the heat exchanger to purify the exhaust gas. Alternatively, the three-way catalyst can also be connected directly to the engine if no turbocharger is present in the vehicle.

[0034] According to one embodiment of the invention, the system further comprises a sensor arranged and configured to detect a hydrogen concentration in the crankcase. Alternatively or additionally, the sensor may be configured to detect a saturation level of the carrier medium. As already mentioned, the sensor may be any type of sensor suitable for this task. The system further comprises a control device configured to control the amount of carrier medium injected into the crankcase based on the detected hydrogen concentration in the crankcase and / or based on the saturation level of the carrier medium or LOHC in the crankcase. The control device may directly control the nozzle or a regulator or valve configured to regulate the amount of carrier medium to be injected into the crankcase by the nozzle.Alternatively or additionally, the control device may be configured to trigger the dehydration of the carrier medium in response to the measured saturation level of the carrier medium.

[0035] According to one embodiment of the invention, the system further comprises a hydrogen tank connected to the heating device and the hydrogen injector. The tank is designed for the temporary storage of the extracted hydrogen. The tank is thus designed to be suitable for hydrogen storage. In this way, the extracted hydrogen can be stored before being reused in the hydrogen combustion engine. Thus, the dehydrogenation reaction can be carried out efficiently even when the motor vehicle is stationary.

[0036] The above embodiments and further developments can be combined with one another as desired, provided this makes sense. In particular, all features of the method for absorbing hydrogen in a crankcase of a hydrogen combustion engine are transferable to the system for a motor vehicle and / or the motor vehicle, and vice versa. Further possible embodiments, further developments, and refinements of the invention also include combinations of features of the invention that are not explicitly mentioned, which are described above or below with reference to the embodiments. In particular, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the present invention.

[0037] The invention is explained in more detail with reference to embodiments shown in the accompanying drawings. Short description of the drawings

[0038] The accompanying drawings provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the present invention and together with the description serve to explain the principles of the invention. Other embodiments of the present invention and many of the intended advantages of the present invention will be readily appreciated as they become better understood by reference to the following detailed description. The elements in the drawings are not necessarily to scale with respect to one another. Throughout the figures, like reference numerals designate like or functionally similar components unless otherwise noted. In Fig. 1 schematically shows a system for a motor vehicle according to an embodiment of the invention; Fig. 2 schematically shows a flow diagram of a method for absorbing hydrogen in a crankcase of a hydrogen combustion engine according to an embodiment of the invention; Fig. 3 schematically shows a crankcase and a collector of a system according to another embodiment of the invention; Fig. 4a and b schematically show a catalyst coating of a surface of the system according to another embodiment of the invention; Fig. 5 schematically shows a flow diagram of a method for absorbing hydrogen in a crankcase of a hydrogen combustion engine according to another embodiment of the invention; Fig. 6 schematically shows a system for a motor vehicle according to an embodiment of the invention; and Fig. shows schematically a motor vehicle according to an embodiment of the invention.

[0039] Although specific embodiments are shown and described herein, those skilled in the art will recognize that the specific embodiments shown and described may be replaced with a variety of alternative and / or equivalent implementations without departing from the scope of the present invention. In general, this application is intended to cover any adaptations or variations of the specific embodiments described herein. Detailed description of the embodiments

[0040] In Fig. 1 schematically shows a system 1 for a motor vehicle 100 according to an embodiment of the invention.

[0041] The system 1 for a motor vehicle 100 comprises a hydrogen combustion engine 10. In the motor vehicle 100 (in Fig. 1 not shown) can be any type of vehicle, such as passenger cars, including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, and the like, and it includes vehicles that burn hydrogen. In addition to motor vehicles, the system 1 can also be used for larger vehicles such as trucks, buses, etc. However, the system 1 can also be applied to other vehicles and even systems with a hydrogen combustion engine 10, such as a ship, a train, an aircraft, or a power plant.

[0042] The internal combustion engine 10 comprises a combustion chamber 12 and a hydrogen injector 11. In addition to the direct injection of hydrogen, the hydrogen injector 11 can also support a distributor injection, in which hydrogen H is injected together with other components. The hydrogen injector 11 is arranged at an upper part of the hydrogen internal combustion engine 10 and designed to inject hydrogen H into the combustion chamber 12. The hydrogen injector 11 receives hydrogen H as fuel via a connected fuel line from a hydrogen storage device (both in Fig. 1 not shown). In addition to hydrogen, oxygen is also fed into the combustion chamber 10 to drive the hydrogen combustion engine 10.

[0043] The hydrogen combustion engine 10 further includes a piston 13 for compressing and expanding the hydrogen H injected into the combustion chamber 12 and the air or air-fuel mixture together with the remaining exhaust gas. The compression and expansion of the combustion chamber 12 is achieved here by connecting the piston 13 to a piston rod 16, which is connected to a rotatable crankshaft 17.

[0044] The hydrogen combustion engine 10 further includes a crankcase 14 disposed on a bottom side 13c of the piston 13 opposite the combustion chamber 12, and a nozzle 15 for injecting a hydrogen carrier medium L into the crankcase 14 to hydrogenate the carrier medium L within the crankcase 14 with hydrogen escaping from the combustion chamber 12 past the side walls 13a of the piston 13 into the crankcase 14. In some embodiments, the nozzle 15 is configured as an injector that injects or sprays the carrier medium L into the crankcase 14.

[0045] The escape of hydrogen H from the combustion chamber 12 past the piston 13 into the crankcase 14 is in Fig. 1 by the dashed arrows. In addition to hydrogen H, oxygen O also regularly enters or is present in the crankcase 14, which, if the hydrogen concentration is too high, leads to an exothermic reaction, i.e., explosion, of the two chemical components. The binding of hydrogen H to the carrier medium L thus reduces the concentration of hydrogen H.

[0046] The carrier medium L is preferably a liquid organic hydrogen carrier (LOHC). LOHCs are organic liquids capable of absorbing and releasing hydrogen through chemical reactions. Therefore, LOHCs can be used for the safe storage and transport of hydrogen. The absorption of hydrogen, hydrogenation, is an exothermic reaction, whereas dehydrogenation requires an energy input and is therefore an endothermic reaction. Typical LOHCs are toluene / methylcyclohexane (C7H8 / C7H14), dibenzyltoluene (C21H20), or benzyltoluene (C14H14). Depending on the liquid, up to 56 kg of hydrogen can be stored in 1m 3 LOHC can be transported.

[0047] The injected carrier medium L is thus hydrogenated in the crankcase 14 to a hydrogenated carrier medium 21. In the case of LOHC as the carrier medium L, the hydrogenation produces [LOHC + H 2] as a chemical product. In some embodiments, a pressure of, for example, 30 to 50 bar may prevail in the crankcase 14 for the hydrogenation reaction. In further embodiments, the hydrogenation reaction may cause a temperature of, for example, 150°C to 200°C in the crankcase 14.

[0048] In this embodiment, the hydrogen carrier medium L is injected into the crankcase 14 in a mixture with a lubricant. Furthermore, in this embodiment, the nozzle 15 is designed as a piston cooling nozzle, piston cooling injector, or piston cooling nozzle. The injection of the carrier medium L and / or the lubricant thus has, in addition to the lubricating effect, also the effect of cooling the piston 13. The nozzle 15 is therefore arranged on an underside 13c of the piston 13 opposite the combustion chamber 12. The underside 13c of the piston 13 thus faces the crankcase 14, while a front or upper side 13b of the piston 13 faces the combustion chamber 12. The injection of the carrier medium L takes place essentially parallel to the movement of the piston 13 during compression, i.e., in the Fig. 1 shown vertical upward direction, in the direction of the piston 13.

[0049] In further embodiments, the hydrogen carrier medium L is designed as a lubricant and is injected into the crankcase 14 without additional lubricant. The carrier medium L is then injected through a separate injector or a different nozzle than the piston cooling nozzle used here.

[0050] The system 1 further comprises a collector 20 for collecting the hydrogenated carrier medium 21 from the crankcase 14. In this embodiment, the collector 20 is arranged on a side of the crankcase 14 opposite the combustion chamber 12. Preferably, the lower side of the crankcase 14 is used to arrange the collector 20 such that the hydrogenated carrier medium 21 falls down the crankcase 14 by gravity.

[0051] A heating device 30 is connected to the collector 20 and is designed to heat the carrier medium 21 for dehydrogenation. In this embodiment, a tube 26 partially penetrates the hydrogenated carrier medium 21 in the collector 20. The tube 26 is designed such that the hydrogenated carrier medium 21 flows to the heating device 30. The heating device 30 heats the carrier medium 21 to start the endothermic dehydrogenation reaction. In this way, dehydrogenated carrier medium 22 is produced and hydrogen H is released. In the case of LOHC as the chemical product, the dehydrogenation reaction begins with [LOHC+H 2 ] to LOHC + H 2 In some embodiments, the heating device 30 for this endothermic reaction is configured to provide temperatures of approximately 250°C to 300°C.

[0052] The nozzle 15 is designed to inject the dehydrated carrier medium 22 into the crankcase 14. This can be done by a direct connection from the heating device 30 to the nozzle 15, as in Fig. 1. In further embodiments, the dehydrated carrier medium 22 can be returned to the collector 20, from where an oil pump pumps the dehydrated carrier medium 22 to the nozzle 15. In both cases, the carrier medium L can be reused over many cycles.

[0053] Fig. 2 schematically shows a flow diagram of a method for absorbing hydrogen H in a crankcase 14 of a hydrogen combustion engine 10 according to an embodiment of the invention.

[0054] The Fig. The method shown in Figure 2 corresponds to the one described above with reference to Fig. 1. The method comprises the step of injecting hydrogen H into a combustion chamber 12 of the hydrogen combustion engine 10 through a hydrogen injector 11. The hydrogen combustion engine 10 is typically installed in a vehicle, e.g., an automobile, a truck, a bus, etc. However, the method can also be applied to other vehicles or installations having a hydrogen combustion engine 10, e.g., a ship, a train, an aircraft, or a power plant.

[0055] In the present case, the internal combustion engine 10 comprises a piston 13 which is designed to compress and expand the hydrogen H injected into the combustion chamber 12.

[0056] The method further comprises the step of injecting S2, preferably spraying, a hydrogen carrier medium L into the crankcase 14 through a nozzle 15, which may be designed as an injector, for hydrogenating the carrier medium L within the crankcase 14 with hydrogen H, which escapes from the combustion chamber 12 past a side wall 13a of the piston 13 into the crankcase 14.

[0057] The method comprises the additional step of collecting S3 the hydrogenated carrier medium 21 from the crankcase 14 through a collector 20.

[0058] A further process step comprises heating S4 of the hydrogenated carrier medium 21 by a heating device 30 to dehydrogenate the carrier medium L, 21 and extracting hydrogen H from the hydrogenated carrier medium L, 21.

[0059] The method shown provides an additional step in which the dehydrated carrier medium L, 22 is injected, preferably sprayed, into the crankcase 14 through the nozzle 15 for hydrogenation S5.

[0060] It is understood that the process described above can be continued continuously or at suitable intervals by repeating the steps of collecting S3 the hydrogenated carrier medium 21, heating S4 the hydrogenated medium 21 for dehydrogenation, and further injecting the dehydrated carrier medium 22 through the nozzle 15 into the crankcase 14. In this way, the hydrogen concentration in the crankcase 14 can be kept low, thereby avoiding an exothermic reaction between the oxygen O and the hydrogen H in the crankcase 14.

[0061] In Fig. 3 schematically shows a crankcase 14 and a collector 20 of a system 1 according to a further embodiment of the invention.

[0062] The Fig. 3 shown crankcase 14 with the piston 13 and the collector is based on the corresponding components of the Fig. 1. However, in this embodiment, a catalyst 18 is provided on a bottom surface 13c of a piston 13 and on a cylinder liner 19a of a cylinder 19 of the hydrogen internal combustion engine 10. The piston 13 is movably arranged and configured in the cylinder 19, as is usual in conventional internal combustion engines 10.

[0063] In this embodiment, the catalyst 18 is formed as a coating. In some embodiments, the catalyst comprises nickel, palladium, and / or platinum alone or in combination. The method for hydrogenating the carrier medium L comprises the use of the catalyst 18, in particular for initiating the exothermic reaction. Furthermore, the heat generated by the exothermic reaction can assist a vehicle during warm-up. The heat can then be dissipated through an engine cooling system or engine cooling circuit, which is regularly present in a motor vehicle.

[0064] The system 1 further comprises a sensor 23, which is arranged and configured to detect the hydrogen concentration in the crankcase 14. The sensor 23 is configured as a gas sensor and is arranged on a side wall of the crankcase 14 below the nozzle 15. In this embodiment, the sensor 23 is designed as an electrochemical gas detector. In further embodiments, the gas sensor is designed as an infrared point sensor or a photoionization detector. Other common types of gas sensors suitable for this task can also be used.

[0065] A control device 24 is connected to the sensor 23 and configured to control an amount of carrier medium L injected into the crankcase 14 based on the detected hydrogen concentration in the crankcase 14. The control device 24 is configured to control the injection of the carrier medium L into the crankcase 14 depending on a demand for carrier medium. In further embodiments, the sensor 23 can be configured to detect a saturation level of the carrier medium. In particular, when the concentration becomes high, i.e., approximately 4% by volume, the control device 24 sends a signal to the nozzle 15 or, in further embodiments, to a valve that can regulate the output of the nozzle 15, in order to inject the carrier medium L into the crankcase 14.The control device 24 can also be configured to regulate the amount of carrier medium L used or mixed with a lubricant according to actual demand. Thus, the sensor 23 detects a concentration of hydrogen H in the crankcase 14, and the control device 24 controls the amount of carrier medium L injected into the crankcase 14 based on the detected concentration of hydrogen H in the crankcase 14. In this way, the carrier medium L can be injected into the crankcase 14 continuously or at suitable injection intervals to keep the hydrogen concentration below a certain threshold, e.g., below 4%.

[0066] In embodiments in which the sensor 23 measures the saturation level of the carrier medium L, the control device 24 may be configured to trigger the dehydration of the carrier medium L in response to the measured saturation level of the carrier medium L.

[0067] Fig. 4a and b schematically show a catalyst coating of a surface of the system 1 according to a further embodiment of the invention.

[0068] In the Fig. In the embodiment shown in Fig. 4a, the catalyst 18 is formed as a coating which can be arranged on an underside 13c of a piston 13 and / or on a cylinder lining 19a of a cylinder 19 of the hydrogen combustion engine 10, as described above.

[0069] This is in Fig. which shows an enlarged view of the Fig. shown section M. A profile of the coating has a roughness on the inner surface 18b facing a substrate 19a, in this case a cylinder liner 19a. In further embodiments, a separate substrate 19a may be applied to the surface of the cylinder 19 facing the piston 13 and to the underside 13c of the piston 13 before the catalyst 18 is applied as a coating. In further embodiments, the substrate 19a is formed as a coating on the piston 13.

[0070] The profile of the inner surface 18b of the catalyst 18 includes depressions and elevations, thereby increasing the surface area to facilitate the reaction of the carrier medium L and the hydrogen H. In further embodiments, the coating of the catalyst 18 is formed as a foam. In some embodiments, the foam is applied to the underside 13c of the piston 13. A foam increases the inner and outer surfaces 18a, 18b of the catalyst 18 available for reaction with the carrier medium L and the hydrogen H.

[0071] Fig. 5 schematically shows a flow diagram of a method for absorbing hydrogen H in a crankcase 14 of a hydrogen combustion engine 10 according to another embodiment of the invention.

[0072] In Fig. 5 is a flowchart showing a process between the components of a system 1 for a motor vehicle. Fig. System 1 shown in Figure 5 is based on the system described above with reference to Fig. System 1 described in 1.

[0073] In this figure, the step of injecting hydrogen H through the hydrogen injector 11 into the combustion chamber 12 is indicated by the arrow S1 pointing toward the element 12. This also applies to the remaining steps S2 and S3 to S5, which are shown here as repeating steps with the nozzle 15 and the collector 20 as well as the heating device 30.

[0074] In addition to steps S1 to S5, the method comprises the step of injecting S6 the hydrogen H extracted from the carrier medium L through the hydrogen injector 11 into the combustion chamber 12 of the hydrogen combustion engine 10. The system 1 described here thus reuses the hydrogen for driving or operating the hydrogen combustion engine 10. In further embodiments, the extracted hydrogen H is simply discharged to the outside.

[0075] Fig. 6 schematically shows a system 1 for a motor vehicle 100 according to an embodiment of the invention.

[0076] The Fig. System 1 shown in Figure 6 is based on the system described above with reference to Fig. 1 and is connected to the system 1 shown and described above with reference to Fig. 3 can be combined with the components shown and described. It is also suitable for carrying out the procedure described so far.

[0077] In addition to the systems 1 described so far, the system 1 of the present embodiment comprises a pump 31, which is connected to the collector 20 and the heating device 30 and is designed to pump the carrier medium L from the collector 20 to the heating device 30. The cooler 32 is thus located at the connection of the line 34, which connects the collector 20 to the heating device 30. In this embodiment, the collector 20 comprises an oil pan or is designed as such. The pump 31 is designed to suck in the hydrogenated carrier medium 21 and to pump the hydrogenated carrier medium 21 from the oil pan to the heating device 30. The pump 31 thus transports the hydrogenated carrier medium 21 to the heating device 30.

[0078] The system 1 further comprises a turbocharger 40, which is connected to the hydrogen combustion chamber 12 and the heating device 30, so that the heating device 30 is heated by an exhaust gas 41 from the turbocharger 40. The heating device 30 is thus designed as a heat exchanger, and the heat of the exhaust gas 41 feeds the heat exchanger 30 to heat the hydrogenated carrier medium 21. In this embodiment, the exhaust gas 41 exits the turbocharger 40 and enters an optional three-way catalyst 42, in which unburned components of the exhaust gas react. The thus purified exhaust gas 42 then enters the heat exchanger 30 to heat the hydrogenated carrier medium 21 for dehydrogenation and to produce dehydrogenated carrier medium 22.

[0079] In the embodiment of Fig. 6 includes the Fig. 6, the system 1 further comprises a cooler 32, which is connected to the heating device 30. The cooler 32 is designed to cool the dehydrated carrier medium 22 before the dehydrated carrier medium 22 is injected back into the crankcase 14 through the nozzle 15. In this embodiment, the cooler 32 is connected to the collector 20 via a connection 34. The collector 20, ie the oil pan, thus contains a mixture of the hydrogenated carrier medium 21 and the dehydrated carrier medium 22. An oil pump (in Fig. 6 not shown) then pumps the carrier medium 21, 22 from the oil pump via a connection 25 to the nozzle 15. In this embodiment, an inlet 25a of the connection 25 is located near an outlet 34a of the connection 34, which directs the dehydrated carrier medium 22 into the oil pan, as in Fig. 6 is shown schematically. The connection 25 can be formed by a pipe. In this way, a large portion of the dehydrated carrier medium 22 is directed to the nozzle 15.

[0080] In this embodiment, the cooler 32 is designed as a heat exchanger and is connected to an engine cooling circuit 33. The engine cooling circuit 33 serves to cool the hydrogen combustion engine 10 and is typically present in a motor vehicle 100.

[0081] Similar to the one with reference to Fig. 5 and System 1 is used in the Fig. 6, the hydrogen H extracted from the carrier medium L is injected S6 through the hydrogen injector 11 into the combustion chamber 12 of the hydrogen combustion engine 10. The elements 10 to 12 are thus in Fig. 6. In this way, the hydrogen H extracted from the hydrogenated carrier medium 21 is reused to drive the hydrogen combustion engine 10. In further embodiments, the extracted hydrogen H is discharged to the outside.

[0082] In further embodiments, the system 1 additionally comprises a hydrogen tank connected to the heating device 30 and the hydrogen injector 11. Such a tank is designed for the temporary storage of the extracted hydrogen H. The extracted hydrogen can be stored in the tank before being reused in the hydrogen combustion engine 10. The dehydrogenation can thus be carried out during a vehicle stop.

[0083] Fig. schematically shows a motor vehicle 100 according to an embodiment of the invention.

[0084] The Fig. The motor vehicle 100 shown in Figure 7 comprises the system 1 described so far. As described above, Fig. Although a motor vehicle 100 is shown in Figure 7, in further embodiments the system 1 is also integrated into other types of vehicles, e.g. a truck, a bus, a ship, a train, an aircraft or in facilities such as a power plant.

[0085] In the foregoing detailed description, various features have been summarized in one or more examples or examples to facilitate disclosure. It is to be understood that the above description is illustrative and not restrictive. It is intended to cover all alternatives, modifications, and equivalents of the various features and embodiments. Many other examples will become apparent to those skilled in the art upon review of the above description. The embodiments were chosen and described in order to explain the principles of the invention and their practical applications, and to thereby enable others skilled in the art to utilize the invention and various embodiments with various modifications as are suited to the particular application. Reference list 1 system 10 Hydrogen combustion engine 11 Hydrogen injector 12 Combustion chamber 13 pistons 13a Side wall of the piston 13b Top of the piston 13c Underside of the piston 14 Crankcase 15 nozzle 16 Piston rod 17 Crankshaft 18 Catalyst 18a Profile of the catalyst 19 cylinders 19a Substrate, cylinder lining 20 Collector / Oil pan 21 hydrated carrier medium 22 dehydrated carrier medium / lubricant 23 Sensor 24 Control device 25 Connection from the oil pan to the nozzle 26 Pipe between collector and heating device 30 Heating device / heat exchanger 31 Pump 32 Radiator / second heat exchanger 33 Engine cooling circuit 34 Pipe between radiator and oil pan 34a Outlet 40 turbochargers 41 Exhaust 42 Three-way catalyst 100 motor vehicles H Hydrogen L Carrier medium M Enlarged section O oxygen S1-S6 process steps QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 10,309,290 B2

[0003]

Claims

[1] A method for absorbing hydrogen (H) in a crankcase (14) of a hydrogen combustion engine (10), comprising: Injecting (S1), by a hydrogen injector (11), hydrogen (H) into a combustion chamber (12) of the hydrogen combustion engine (10); wherein a piston (13) of the hydrogen combustion engine (10) is configured to compress and expand the hydrogen (H) injected into the combustion chamber (12); Injecting (S2), through a nozzle (15), a hydrogen carrier medium (L) into the crankcase (14) for hydrogenating the carrier medium (L) within the crankcase (14) with hydrogen (H) escaping from the combustion chamber (12) past a side wall (13a) of the piston (13) into the crankcase (14); Collecting (S3), through a collector (20), the hydrogenated carrier medium (21) from the crankcase (14); Heating (S4), by a heating device (30), the hydrogenated carrier medium (21) to dehydrogenate the carrier medium (L, 21) and extract hydrogen (H) from the hydrogenated carrier medium (L, 21); and Injecting (S5), through the nozzle (15), the dehydrated carrier medium (L, 22) into the crankcase (14) for hydrogenation. [2] Method according to claim 1, wherein the hydrogen carrier medium (L) is injected into the crankcase (14) in a mixture with a lubricant. [3] Method according to claim 1 or 2, wherein the hydrogen carrier medium (L) is designed as a lubricant and is injected into the crankcase (14) without an additional lubricant. [4] Method according to one of the preceding claims, wherein the nozzle (15) is designed as a piston cooling nozzle, and wherein the nozzle (15) is arranged on an underside (13c) of the piston (13) opposite the combustion chamber. [5] Process according to one of the preceding claims, wherein the hydrogenation of the carrier medium (L) comprises the use of a catalyst (18). [6] The method of claim 5, wherein the catalyst (18) comprises at least one of the elements nickel, palladium and platinum. [7] Method according to claim 5 or 6, wherein the catalyst (18) is formed as a coating on an underside (13c) of a piston (13) and / or on a cylinder lining (19a) of a cylinder (19) of the hydrogen combustion engine (12). [8] A method according to claim 7, wherein the coating is formed as a foam. [9] Method according to one of the preceding claims, wherein the collector (20) comprises an oil pan, wherein a pump (31) is arranged to suck the hydrogenated carrier medium (L, 21) from the oil to the heating device (30). [10] Method according to one of the preceding claims, wherein the heating device (30) is designed as a heat exchanger, and further comprising: Supplying an exhaust gas (41) to the heat exchanger (30) for heating the hydrogenated carrier medium (L., 21). [11] Method according to claim 10, wherein the exhaust gas (41) is supplied from a turbocharger (40) which is connected to the hydrogen combustion engine (10) and the heat exchanger (30). [12] Method according to one of the preceding claims, further comprising: Cooling, by a cooler (32), the carrier medium (L, 22) after dehydration. [13] Method according to claim 12, wherein the cooler (32) is designed as a heat exchanger and is connected to an engine cooling circuit (33) which is designed to cool the hydrogen combustion engine (10). [14] A method according to any one of the preceding claims, further comprising: Injecting (S6), through the hydrogen injector (11), the hydrogen (H) extracted from the carrier medium (L) into the combustion chamber (12) of the hydrogen combustion engine (10). [15] A method according to any one of the preceding claims, further comprising: Detecting, by a sensor (23), a concentration of hydrogen (H) in the crankcase (14) and / or a saturation level of the carrier medium (L), and Controlling, by a control device (24), the amount of carrier medium (L) injected into the crankcase (14) on the basis of the detected concentration of hydrogen (H) in the crankcase (14) and / or on the basis of the detected saturation level of the carrier medium (L). [16] System (1) for a motor vehicle (100), comprising a hydrogen combustion engine (10) with a combustion chamber (12), a hydrogen injector (11) for injecting hydrogen (H) into the combustion chamber (12), a piston (13) for compressing and expanding the hydrogen (H) injected into the combustion chamber (12), a crankcase (14) arranged on an underside (13c) of the piston (13) opposite the combustion chamber (12), and a nozzle (15) for injecting a hydrogen carrier medium (L) into the crankcase (14) for hydrogenating the carrier medium (L) within the crankcase (14) with hydrogen (H), which escapes from the combustion chamber (12) past the side walls (13a) of the piston (13) into the crankcase (14); a collector (20) for collecting the hydrogenated carrier medium (L, 21) from the crankcase (14); and a heating device (30) connected to the collector (20) and designed to heat the carrier medium (L, 21) to obtain a dehydrated carrier medium (L, 22), wherein the nozzle (15) is designed to inject the dehydrated carrier medium (L, 22) into the crankcase (14). [17] System (1) according to claim 16, further comprising a pump (31) connected to the collector (20) and the heating device (30) and configured to pump the carrier medium (L, 21) from the collector (20) to the heating device (30). [18] System (1) according to one of claims 16 or 17, further comprising a cooler (32) connected to the heating device (30), wherein the cooler (32) is adapted to cool the dehydrated carrier medium (L, 22) before the cooled and dehydrated carrier medium (L, 22) is injected back into the crankcase (14). [19] System (1) according to claim 18, wherein the cooler (32) is connected to an engine cooling circuit (33) which is designed to cool the hydrogen combustion engine (10). [20] System (1) according to one of claims 16 to 19, further comprising a turbocharger (40) connected to the hydrogen combustion chamber (12) and the heater (30) such that the heater (30) is heated by an exhaust gas (41) of the turbocharger (40). [21] System (1) according to one of claims 16 to 20, further comprising a sensor (23) arranged and configured to detect a hydrogen concentration in the crankcase (14), and a control device (24) configured to control an amount of the carrier medium (L) injected into the crankcase (14) on the basis of the detected hydrogen concentration and / or the degree of saturation of the carrier medium (L) in the crankcase (14). [22] System (1) according to one of claims 16 to 21, further comprising a hydrogen tank connected to the heating device (30) and the hydrogen injector (11), the tank being designed for the intermediate storage of the extracted hydrogen (H). [23] Motor vehicle (100) with the system (1) according to one of the preceding claims.

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