Method of operating a hydrogen combustion engine, control device, combustion engine system and vehicle

Abstract

A control device (100) and method for operating a hydrogen direct injection compression ignition combustion engine (3). The method comprises injecting (S101) a pilot agent into the combustion chamber (35), thereby promoting auto-ignition of hydrogen gas fuel, wherein the pilot agent consists of a solution comprising hydrogen peroxide. The present disclosure also relates to a combustion engine system (10) comprising a direct injection compression ignition combustion engine (3) operable with hydrogen and the control device (100). The combustion engine system (10) can be comprised in a vehicle (1).

Description

Technical Field

[0001] This disclosure generally relates to a method of operating a hydrogen direct injection compression ignition engine. This disclosure also generally relates to a control device configured to control the operation of the hydrogen direct injection compression ignition engine.

[0002] This disclosure also relates generally to combustion engine systems and vehicles including said combustion engine systems. Furthermore, this disclosure generally relates to a computer program and a computer-readable medium. Background Technology

[0003] Efforts to reduce emissions have prompted automakers to explore various technologies, such as vehicle electrification or the use of carbon-free fuels in combustion engines. Electrifying heavy-duty vehicles is not an easy task, for example, because it requires very large battery packs. These battery packs increase vehicle costs, add weight, and often reduce available cargo space. Both the increased weight and reduced cargo space affect vehicle operating costs. Furthermore, the extended recharge duration of heavy-duty vehicle batteries can pose challenges, especially until further advancements in fast-charging technologies and infrastructure for heavy-duty vehicles are developed. Moreover, the shortage of infrastructure for the mass production of batteries for these types of vehicles is unlikely to be resolved quickly in the short term. Therefore, at least in the short and medium term, combustion engines remain a viable solution for heavy-duty vehicles.

[0004] One example of a carbon-free fuel that can be used in conventional combustion engines is hydrogen. Given the high cost of hydrogen and the higher efficiency of compression-ignition engines compared to so-called Otto cycle engines, compression-ignition engines are preferred for hydrogen fuel applications. However, a major challenge when attempting to utilize hydrogen fuel in compression-ignition engines relates to fuel ignition. Unlike diesel fuel, which has a moderate ignition temperature and readily auto-ignites in compression-ignition engines, hydrogen exhibits a very high ignition temperature. Therefore, a combustion initiator or igniter becomes necessary when hydrogen is used as fuel in a compression-ignition engine.

[0005] One potential approach is to use electronic spark plugs or glow plugs to initiate combustion. However, this has the disadvantage of requiring, for example, a redesign of the cylinder head of the combustion engine.

[0006] Another approach involves injecting a small amount of diesel fuel as a pilot. This allows the diesel fuel to ignite spontaneously, creating a high-temperature domain that can serve as an ignition source for the primary fuel (i.e., hydrogen). While effective, the injected diesel fuel contains carbon atoms, resulting in a limited amount of carbon dioxide being formed within the engine. This minimal emission reduction, though significant, may prevent vehicles that include combustion engines from being classified as zero-emission vehicles. Therefore, the use of diesel pilots can be seen as a short-term transitional solution in efforts to decarbonize vehicles to achieve carbon neutrality and zero carbon emissions. Summary of the Invention

[0007] The object of this invention is to provide an alternative method for hydrogen auto-ignition that reduces, and preferably eliminates, the need for diesel pilot agents.

[0008] The objective is achieved through the subject matter of each of the appended independent claims.

[0009] According to this disclosure, a method for operating a hydrogen direct injection compression ignition (HICI) engine is provided. The engine includes a cylinder and a piston configured to reciprocate within the cylinder and connected to a rotatable crankshaft. The cylinder and piston, together with a cylinder head, form a combustion chamber. The method includes the step of injecting a pilot agent into the combustion chamber to promote the auto-ignition of hydrogen fuel, wherein the pilot agent comprises a solution containing hydrogen peroxide.

[0010] Compared to the use of diesel pilots to generate a high-temperature domain to facilitate the auto-ignition of hydrogen, the method described herein relies on generating a chemically reactive domain to facilitate the auto-ignition of hydrogen fuel. This is achieved through a pilot containing hydrogen peroxide.

[0011] The method described herein enables the spontaneous combustion of hydrogen fuel without the injection of a diesel pilot. This, in turn, allows the operation of combustion engines without producing carbonaceous substances such as CO and / or CO2 or HC.

[0012] Furthermore, by promoting the spontaneous combustion of hydrogen, the method described herein enables the use of compression ignition engines. Compression ignition engines are known to be more efficient than spark ignition engines when using hydrogen as fuel. This advantage is particularly important considering the high cost of hydrogen as a fuel.

[0013] The solution containing hydrogen peroxide can preferably be an aqueous solution. especially Facilitates the storage and handling of lead solutions. In some cases, aqueous solutions can also reduce the amount of NOx produced during combustion.

[0014] For example, the pilot injection can be initiated at a crankshaft angle of less than 30° prior to the start of hydrogen fuel injection. This further promotes the auto-ignition of hydrogen fuel because it reduces the loss of hydrogen peroxide and its resulting intermediates prior to hydrogen fuel injection. Preferably, the pilot injection can be initiated at a crankshaft angle of equal to or less than 20° prior to the start of hydrogen fuel injection.

[0015] The pilot agent can be injected during a time period corresponding to a crankshaft angle of 20° or less. Therefore, the amount of pilot agent consumed during engine operation can be kept low. For example, the pilot agent can be injected during a time period corresponding to a crankshaft angle difference of 10° or less.

[0016] The concentration of hydrogen peroxide in the solution can be, for example, at least 5% by weight, preferably at least 10% by weight. Higher concentrations of hydrogen peroxide... especially This reduces the amount of solution that needs to be injected into the combustion chamber as a pilot agent in order to generate the desired chemically active domain.

[0017] Furthermore, the concentration of hydrogen peroxide in the solution can appropriately be up to 60% by weight. Therefore, the risk of corrosion problems can be reduced, and the treatment of the solution can also be facilitated. Preferably, the concentration of hydrogen peroxide in the solution is up to 50% by weight.

[0018] For example, the operation of the combustion engine can achieve a combustion chamber temperature of 800K to 1100K, and appropriately 900K to 1050K. This contrasts with situations requiring higher temperatures without any combustion initiator or igniter; the chemically active domain generated according to this method enables operation at the aforementioned lower temperatures. Lower temperatures especially It has the advantage of reducing the amount of NOx produced.

[0019] The pilot fuel can be properly injected by using a dual-fuel injector, which is configured to inject the pilot fuel and hydrogen fuel separately into the combustion chamber. especially It has the advantage of allowing the pilot fuel and hydrogen fuel to be injected into the combustion chamber in very close and substantially the same direction, thus ensuring that the hydrogen fuel will come into contact with the chemically active domain generated by the pilot fuel injection. Furthermore, the use of dual-fuel injectors avoids the need to redesign a basic conventional diesel combustion engine to implement separate injectors for the pilot fuel and hydrogen fuel.

[0020] According to one aspect, the spontaneous combustion of hydrogen fuel can be carried out in the presence of a catalyst. This catalyst can reduce the time required for hydrogen and hydrogen peroxide to convert into intermediate substances, and thus can further promote the spontaneous combustion of hydrogen fuel.

[0021] This disclosure also relates to a computer program including instructions that, when executed by a computer, cause the computer to perform the methods described above.

[0022] This disclosure also relates to a computer-readable medium including instructions that, when executed by a computer, cause the computer to perform the methods described above.

[0023] The present invention also provides a control device configured to control the operation of a hydrogen direct injection compression ignition combustion engine. The combustion engine includes a cylinder and a piston configured to reciprocate within the cylinder and connected to a rotatable crankshaft. The cylinder and piston, together with the cylinder head, form a combustion chamber. The control device is configured to inject a pilot agent into the combustion chamber to promote the auto-ignition of hydrogen fuel, wherein the pilot agent consists of a solution containing hydrogen peroxide.

[0024] The control device provides the same advantages as those described above with reference to the corresponding method for operating a hydrogen direct injection compression ignition engine.

[0025] The control device can be configured to initiate pilot injection at a crankshaft angle less than 30° prior to the start of hydrogen fuel injection. Preferably, the control device can be configured to initiate pilot injection at a crankshaft angle equal to or less than 20° prior to the start of hydrogen fuel injection.

[0026] This disclosure also relates to a combustion engine system comprising: a direct injection compression ignition combustion engine capable of operating using hydrogen fuel; and a control device as described herein, configured to control the operation of the hydrogen direct injection compression ignition combustion engine.

[0027] The combustion engine system provides the same advantages as those described above with reference to the corresponding method for operating a hydrogen direct injection compression ignition combustion engine.

[0028] The combustion engine system can advantageously include a dual-fuel injector configured to inject a pilot gas and hydrogen fuel separately into the combustion chamber of the combustion engine. As mentioned above, this has the advantage of ensuring contact between the hydrogen fuel and the chemically active domain generated by the pilot gas injection. Furthermore, the use of a dual-fuel injector avoids the need to redesign the combustion engine to implement separate injectors for the pilot gas and hydrogen fuel.

[0029] The combustion engine system may also include a storage container configured to store a solution containing hydrogen peroxide. The storage container may be fluidly connected to an injector via a fluid communication line, wherein the injector is configured to inject at least a pilot agent into the combustion chamber of the combustion engine. Optionally, the combustion engine system may also include a concentration regulating device disposed in the fluid communication line, wherein the concentration regulating device is configured to adjust the concentration of hydrogen peroxide in the solution flowing through the communication line. especially This has the advantage of enabling smaller storage containers for solutions containing hydrogen peroxide and / or reducing the frequency at which said storage containers must be replenished.

[0030] If necessary, the combustion engine system may also include a catalyst arranged in the combustion chamber of the combustion engine. This can further promote the spontaneous combustion of hydrogen fuel.

[0031] This disclosure also relates to a vehicle including the combustion engine system described above. The vehicle can be a land-based vehicle. For example, the vehicle can be a land-based heavy vehicle, such as a bus or truck. Alternatively, the vehicle can be a water-based vehicle. Attached Figure Description

[0032] Figure 1 A side view of an example vehicle is shown schematically. Figure 2 A schematic cross-sectional view of an example cylinder of a direct injection compression ignition engine is shown. Figure 3 A side view of the tip of an example dual-fuel injector is shown. Figure 4 An exemplary embodiment of a combustion engine system according to this disclosure is schematically illustrated. Figure 5 The flowchart schematically illustrates the method described herein for operating a hydrogen direct injection compression ignition engine, and... Figure 6 An exemplary embodiment of the apparatus is schematically shown, which may include, be constituted by, or be included in a control device, wherein the control device is configured to perform the method described herein for operating a hydrogen direct injection compression ignition engine. Detailed Implementation

[0033] The invention will now be described in more detail with reference to exemplary embodiments and the accompanying drawings. However, the invention is not limited to the exemplary embodiments discussed and / or shown in the drawings, but may vary within the scope of the appended claims. Furthermore, the drawings should not be considered to be drawn to scale, as some features may have been enlarged to illustrate the invention or its features more clearly.

[0034] This disclosure provides a method for operating a hydrogen direct injection compression ignition (HCI) engine, such as a hydrogen direct injection compression ignition (HCI) engine for a vehicle. This method can be executed by a control device configured accordingly. The HCI engine includes one or more cylinders. Each cylinder includes a piston configured to reciprocate within the cylinder. The piston is connected to a rotatable crankshaft of the combustion engine. Furthermore, each cylinder, together with the piston and the cylinder head, forms a combustion chamber. The reciprocating motion of the piston is converted into rotation of the crankshaft. Therefore, the position of the piston within the cylinder can be described by the crankshaft angle (commonly abbreviated as CA). The combustion engine also includes at least one injector configured to inject fuel into the combustion chamber. The combustion engine is a four-stroke combustion engine.

[0035] This method includes the step of injecting a pilot agent into a combustion chamber to promote the auto-ignition of hydrogen fuel, wherein the pilot agent consists of a solution containing hydrogen peroxide. The injection of the pilot agent may suitably be performed during the compression stroke of the combustion engine, or at least initiated during the compression stroke. However, in some cases, the injection of the pilot agent may alternatively be initiated during the combustion stroke of the combustion engine.

[0036] Pilot injection is a separate injection from the main fuel (i.e., in this case, hydrogen) injection, and is a smaller quantity compared to the main fuel injection. Pilot injection is typically performed at least partially before the main fuel injection.

[0037] In addition to hydrogen peroxide, the solution sprayed as a pilot agent according to the method described herein may suitably contain a solvent. This solvent can be any carbon-free solvent miscible with hydrogen peroxide. If desired, the solution may also contain one or more additives. For example, the solution may contain one or more additives for improving solution stability, such as phosphoric acid or other inorganic acids. Alternatively or additionally, the solution may contain one or more compounds for improving solution lubricity. Alternatively or additionally, the solution may contain one or more carbon-free compounds that can further promote the auto-ignition of hydrogen, for example, by decomposition into active substances.

[0038] Hydrogen peroxide is a compound with the chemical formula H₂O₂. It is a cost-effective compound used in a wide range of applications, from cosmetic and pharmaceutical uses (such as bleaching agents or preservatives) to industrial uses (such as chemical production, pulp and paper bleaching, or textile bleaching). Hydrogen peroxide is not a fuel and does not react directly with oxygen. Instead, under certain conditions, it decomposes into intermediates, which then convert into oxygen and water.

[0039] Hydrogen peroxide is miscible with water in any proportion. Pure hydrogen peroxide is a liquid in the temperature range of 0°C to 150°C. However, in aqueous solution, hydrogen peroxide forms a eutectic mixture, which results in a lower freezing point of the aqueous solution. For example, when the H₂O₂ concentration is approximately 40% to 70% by weight, the freezing point of this aqueous solution is equal to or below -40°C. Hydrogen peroxide can be stored stably in aqueous solution. However, at higher hydrogen peroxide concentrations, stabilizing additives can be appropriately added to the aqueous solution to improve stability.

[0040] Typically, the auto-ignition process of hydrogen fuel involves the conversion of hydrogen and oxygen into various intermediates and chain radicals, such as H₂O₂, HO₂, OH, H, and O atoms. These intermediates eventually transform into water, H₂O, and oxygen (O₂). Under normal operating conditions of a combustion engine, without any ignition assistance, the conversion of hydrogen and oxygen into intermediates is relatively slow, resulting in a long auto-ignition delay time for hydrogen. For example, under engine conditions at approximately 1000 K, the time delay can typically be on the order of about 10 milliseconds, which corresponds to approximately 72 degrees of crankshaft angle (CAD) at 1200 rpm.

[0041] The method described herein involves injecting a small amount of one of the aforementioned intermediates, H₂O₂, as a pilot agent into the combustion chamber shortly before (a few milliseconds) or at the start of hydrogen fuel injection. Under combustion chamber conditions, the injected H₂O₂ sequentially decomposes into other chemical substances, including HO₂, OH, H, and O. Hydrogen peroxide and its derivatives create a chemically active domain. As long as this chemically active domain is active (i.e., the intermediate has not yet been fully converted into H₂O and O₂), it will essentially bypass or at least significantly accelerate the initial conversion of the primary hydrogen fuel to the intermediate when the fuel is injected. This, in turn, allows the hydrogen fuel to auto-ignite in a much shorter timeframe and eliminates the need for the high-temperature domain present when using diesel pilot agents.

[0042] Hydrogen peroxide and its intermediates have transient properties and will convert to water and oxygen under combustion chamber conditions. Therefore, it is important that hydrogen peroxide is injected directly into the combustion chamber to ensure it effectively promotes the auto-ignition of hydrogen fuel. For example, if hydrogen peroxide is instead introduced, for instance, via the intake air, it and its intermediates may not survive until the hydrogen fuel injection is performed. It is also conceivable to add hydrogen peroxide to the hydrogen fuel before it is injected into the combustion chamber. However, this alternative may present safety concerns and makes it difficult to control the appropriate amount of hydrogen peroxide added. Therefore, according to the method described herein, hydrogen peroxide is introduced directly into the combustion chamber as a pilot agent consisting of a solution containing hydrogen peroxide. In other words, the pilot agent and hydrogen fuel are introduced into the combustion chamber as separate injections.

[0043] The injection of the pilot agent into the combustion chamber can be initiated shortly before the hydrogen fuel injection. To ensure that the chemically active domain persists until the hydrogen fuel is injected and should be ignited, the pilot agent injection should be initiated at a crankshaft angle less than 30° prior to the crankshaft angle at which the hydrogen fuel injection is initiated. Reducing the difference between the pilot agent injection initiation time and the hydrogen fuel injection initiation time will result in a reduction in the mass of intermediates that may be lost before auto-ignition, and thus a reduction in the amount of hydrogen peroxide required for injection. Therefore, the pilot agent injection can be initiated at a crankshaft angle equal to or less than 20° prior to the crankshaft angle at which the hydrogen fuel injection is initiated, or even at a crankshaft angle equal to or less than 10° prior to the crankshaft angle at which the hydrogen fuel injection is initiated. Furthermore, the pilot agent injection should be initiated at the latest at the same crankshaft angle as the hydrogen fuel injection initiation.

[0044] The method described herein requires only a very limited amount of hydrogen peroxide to generate the desired chemically active domain, thereby promoting the auto-ignition of hydrogen fuel. Therefore, the pilot injection can be performed over a relatively short time period. This means that the pilot injection can be appropriately performed over a time period corresponding to a crankshaft angle difference of 20° or less. It should be noted here that this means the termination of the pilot injection can occur before, simultaneously with, or after the initiation of hydrogen fuel injection. Appropriately, the pilot injection can be performed over a time period corresponding to a crankshaft angle difference of 10° or less (e.g., approximately 5° to 10° crankshaft angle difference).

[0045] The appropriate amount of pilot agent injected into the combustion chamber to generate the desired chemically active domain depends on the concentration of hydrogen peroxide in the solution. However, the amount of hydrogen peroxide introduced by the solution injected into the combustion chamber as a pilot agent can, for example, be from 0.5 mg to 10 mg. This applies to every case where autoignition of hydrogen fuel is to be achieved, i.e., corresponding to each cycle of the cylinder including the combustion chamber. Suitably, the amount of hydrogen peroxide introduced into the combustion chamber via the pilot agent according to this method can be from 0.5 mg to 5 mg.

[0046] As previously stated, the solution sprayed as a lead agent according to this disclosure may contain a solvent. The solvent may suitably be water, but is not limited thereto. Therefore, according to an alternative, the solution sprayed as a lead agent is an aqueous solution of hydrogen peroxide. This solution may consist of water and hydrogen peroxide. Alternatively, in addition to water and hydrogen peroxide, the solution may also contain various additives as described above and / or one or more additional solvents (if desired). Any carbon-free solvent miscible with hydrogen peroxide may be used as such an additional solvent.

[0047] While lower concentrations are also feasible, the concentration of hydrogen peroxide in the solution can suitably be at least 5% by weight. According to one example, the concentration of hydrogen peroxide in the solution can be at least 10% by weight, or even at least 15% by weight. Increasing the concentration of hydrogen peroxide in the solution reduces the amount of pilot agent that needs to be injected into the combustion chamber. Furthermore, increasing the concentration of hydrogen peroxide in the aqueous solution has the advantage of lowering the freezing point of the solution, which may be advantageous when performing this method on combustion engines of vehicles operating in cold climates.

[0048] Furthermore, the concentration of hydrogen peroxide in the solution is preferably at most 60% by weight. At higher concentrations, various components of the combustion engine system (such as pipes, pipelines, and storage tanks) may be at increased risk of corrosion.

[0049] Furthermore, a hydrogen peroxide concentration exceeding 60% by weight may lead to stability issues with the solution during storage, and therefore poses a safety risk if the solution does not contain a relatively high amount of stabilizing additives. Preferably, the concentration of hydrogen peroxide in the solution can be up to 50% by weight.

[0050] The methods described herein generate chemically active domains, allowing the combustion engine to operate at lower temperatures within the combustion chamber. This is because the methods described herein do not rely on the generation of high-temperature domains to achieve the auto-ignition of hydrogen fuel. Lower temperatures in the combustion engine offer numerous advantages, including, for example, lower temperature loads on the combustion chamber walls and lower NOx production. Therefore, the methods described herein may include operating the combustion engine such that, at least during pilot injection, the temperature within the combustion chamber is between 800 K and 1100 K. As an example, the methods described herein may include operating the combustion engine such that the temperature within the combustion chamber is between 900 K and 1050 K.

[0051] A pilot fuel can be properly introduced into the combustion chamber using a so-called dual-fuel injector. A dual-fuel injector is an injector configured to inject a pilot fuel (typically a pilot fuel comprising a first fuel, but in this case, a solution containing hydrogen peroxide) and a main fuel separately. This can be achieved using separate sets of nozzles for the pilot fuel and the main fuel, respectively. Such dual-fuel injectors are known in the art, for example, for injecting diesel pilot fuel and main fuel (such as hydrogen or natural gas) separately. Examples of dual-fuel injectors that can be used to inject a pilot fuel according to the methods described herein are described in WO 03 / 044358 A1 and US 8,800,529 B2. especiallyThis design offers the advantage of enabling pilot fuel injection and main fuel injection in substantially the same direction relative to the combustion chamber (e.g., from the central axis towards the combustion chamber wall). This, in turn, ensures that the hydrogen fuel contacts the chemically active domain generated by the pilot fuel injection according to this disclosure. Furthermore, the use of a dual-fuel injector reduces the need for modifications to the cylinder head to enable pilot fuel injection.

[0052] However, it should be noted that, if desired, the pilot agent and hydrogen fuel can also be injected via separate injectors. Therefore, according to an alternative exemplary embodiment of the method described herein, the pilot agent is injected into the combustion chamber using a pilot agent injector separate from the injector configured to inject hydrogen fuel. However, it should be noted that if separate injectors are used to inject the pilot agent and hydrogen fuel, the injectors should be arranged such that the hydrogen fuel contacts the chemically active domain generated by the pilot agent injection.

[0053] Although not strictly necessary, the auto-ignition of hydrogen fuel can be further aided by previously known methods. For example, spark plugs or glow plugs can be used for this purpose. Diesel pilot injection technology can also be utilized. In this case, the amount of diesel fuel injected can be reduced compared to existing methods.

[0054] Furthermore, the conversion of hydrogen fuel to the aforementioned intermediates can be accelerated by using catalysts such as platinum, palladium, or silver. Therefore, the spontaneous combustion of hydrogen fuel can optionally be performed in the presence of a catalyst. If so, the catalyst is arranged in the combustion chamber of the combustion engine.

[0055] The execution of the methods for operating a hydrogen direct injection compression ignition engine described herein can be controlled by program instructions. These programming instructions are typically in the form of a computer program that, when executed by a computer, causes the computer to perform the desired form of control action. Such a computer may, for example, be included in the control device described herein. Therefore, this disclosure also relates to a computer program comprising instructions that, when executed by the control device described herein, cause the control device to perform the methods for operating a hydrogen direct injection compression ignition engine described herein. In this disclosure, "computer" is considered to mean any hardware or hardware / firmware device implemented using processing circuitry, such as, but not limited to, a processor, central processing unit (CPU), controller, arithmetic logic unit (ALU), digital signal processor, microcomputer, field-programmable gate array (FPGA), system-on-a-chip (SoC), programmable logic unit, microprocessor, application-specific integrated circuit, or any other device capable of electronically performing operations in a defined manner.

[0056] The programming instructions described above, which may be in the form of a computer program, can be stored on a computer-readable medium. Therefore, this disclosure also relates to a computer-readable medium storing instructions that, when executed by a computer, cause the computer to perform the methods described herein for operating a hydrogen direct injection compression ignition engine. The computer-readable medium can be a non-transitory computer-readable medium, such as tangible electronic, magnetic, optical, infrared, electromagnetic, and / or semiconductor systems, devices, and / or apparatuses.

[0057] This disclosure also relates to a control device configured to control the operation of a hydrogen direct injection compression ignition engine. The control device can be configured to perform any of the steps in the method for operating a hydrogen direct injection compression ignition engine as described above.

[0058] More specifically, according to this disclosure, a control device configured to control the operation of a hydrogen direct injection compression ignition (HCI) engine is provided. The HCI engine includes a cylinder and a piston configured to reciprocate within the cylinder, wherein the piston is connected to a rotatable crankshaft. The cylinder and piston, together with the cylinder head, form a combustion chamber. The control device is configured to inject a pilot agent into the combustion chamber to promote the auto-ignition of hydrogen fuel, wherein the pilot agent comprises a solution containing hydrogen peroxide.

[0059] As previously stated, pilot injection should preferably be initiated shortly before hydrogen fuel is injected into the combustion chamber. Therefore, the control device can be configured to initiate pilot injection at a crankshaft angle less than 30° prior to the start of hydrogen fuel injection. Alternatively, the control device can be configured to initiate pilot injection at a crankshaft angle equal to or less than 20°, or even equal to or less than 10° prior to the start of hydrogen fuel injection.

[0060] The control unit can be further configured to inject hydrogen fuel into the combustion engine.

[0061] The control device may include one or more control units. Where the control device includes multiple control units, each control unit may be configured to control a certain function / step, or a certain function / step may be divided among more than one control unit. The control device may be a control device for a combustion engine system, including a direct injection compression ignition (CICI) engine. Alternatively, the control device may be any other control device of the vehicle, but configured to communicate with the CICI engine to perform the methods described herein.

[0062] This disclosure also relates to a combustion engine system. The combustion engine system includes a direct injection compression ignition combustion engine capable of operating using hydrogen fuel and the aforementioned control device.

[0063] The combustion engine of the combustion engine system may preferably include a dual-fuel injector configured to inject a pilot agent and hydrogen fuel separately into the combustion chamber of the combustion engine.

[0064] The combustion engine system may also include a storage container configured to store a solution containing hydrogen peroxide. The storage container is fluidly connected via a fluid communication line to an injector configured to inject at least a pilot agent into the combustion chamber of the combustion engine. The combustion engine system may also include a concentration regulating device disposed in the fluid communication line, configured to adjust the concentration of hydrogen peroxide in the solution flowing through the fluid communication line. The concentration regulating device may, for example, be configured to control the concentration of hydrogen peroxide in the solution by diluting the solution with a solvent (such as water) flowing through the fluid communication line. Therefore, the storage container can store a solution with a higher hydrogen peroxide concentration than the solution to be injected into the combustion chamber as a pilot agent. This has the advantage of reducing the size of the required storage container and / or the frequency of replenishment. This is particularly advantageous when the combustion engine system is included in a vehicle, as the space available for the storage container on the vehicle may be limited, and the infrastructure in the geographical area where the vehicle operates may not support the frequent replenishment of the hydrogen peroxide-containing solution as with hydrogen refueling. In fact, considering the relatively low amount of hydrogen peroxide required to promote the auto-ignition of hydrogen fuel, it is believed that the presence of a concentration regulating device would allow the hydrogen peroxide solution to be replenished at intervals exceeding one month, even if the vehicle is running continuously. As merely an illustrative example, the solution stored in the storage container could be an aqueous solution with a hydrogen peroxide concentration exceeding 40% by weight, while the hydrogen peroxide concentration of the solution injected into the combustion chamber as a pilot agent could be less than 15% by weight; this concentration difference is achieved by diluting the initial aqueous solution with water.

[0065] If necessary, the aforementioned control device can be configured to control the concentration regulating device. Alternatively, the concentration regulating device can be controlled by a separate controller configured for this purpose.

[0066] If desired, the combustion engine of the combustion engine system may include additional features that can assist in the ignition of hydrogen fuel. For example, the combustion engine may include spark plugs or glow plugs. Alternatively or additionally, the combustion engine may include means for injecting diesel pilot fuel.

[0067] Advantageously, the combustion engine may include a catalyst disposed in the combustion chamber (preferably in each combustion chamber of the combustion engine). The catalyst may be configured to promote the conversion of hydrogen fuel into the aforementioned intermediates. This will further promote the auto-ignition of the hydrogen fuel. The catalyst may include, for example, platinum, palladium, or silver. The catalyst may be disposed, for example, in the combustion chamber, near the tip of the injector (e.g., as a coating on a screen), or on the surface of the piston, valve, or injector support.

[0068] Figure 1 A schematic side view of an example vehicle 1 is shown. Vehicle 1 includes a vehicle powertrain 2. Vehicle powertrain 2 includes a combustion engine 3 and a transmission 4. The combustion engine 3 is a direct injection compression ignition combustion engine that can operate using hydrogen fuel. The combustion engine 3 can be connected to the transmission 4 via a clutch (not shown). The transmission 4 can be connected to the drive wheels 5 of vehicle 1 via a driveshaft 6. Vehicle 1 can be a heavy-duty land-based vehicle, such as a truck or bus, but is not limited thereto. Vehicle 1 can also be, for example, a lighter land-based vehicle.

[0069] Vehicle 1 may also include a control device 100 configured to control the operation of combustion engine 3. The control device 100 may be configured to control the operation of combustion engine 3 according to the methods described herein for operating a hydrogen direct injection compression ignition combustion engine.

[0070] Figure 2 A direct injection compression ignition engine (such as...) is schematically shown. Figure 1 A cross-sectional view of an example cylinder 30 of the combustion engine 3) of the vehicle 1 shown. A piston 31 is arranged in the cylinder 30. The piston 31 is configured to reciprocate along a central axis A within the cylinder 30, thereby rotating the crankshaft 32 of the combustion engine. The piston 31 includes a piston recess (not shown) formed as a receiving cavity in the upper surface of the piston. The upper surface of the piston (including the piston recess) together with the inner wall 33 of the cylinder 30 and the inner surface of the cylinder head 34 forms a combustion chamber 35. A dual-fuel injector 36, configured to inject a pilot fuel and a main fuel (such as hydrogen fuel) into the combustion chamber 35 respectively, may be positioned, for example, on the central axis A above the piston 31. An intake port 37 is provided in the cylinder head 34 for supplying air to the combustion chamber 35 via an intake valve 38. In addition, an exhaust port 39 is provided in the cylinder head 34 for discharging exhaust gases via an exhaust valve 40.

[0071] Figure 3 The image shows a side view of the tip of an example dual-fuel injector, which may be... Figure 2The fuel injector 36 is shown. The tip is configured to extend from the cylinder head 34 into the combustion chamber 35. As shown, the tip includes a first nozzle group 41 and a second nozzle group 42. The first nozzle group 41 is configured to inject a primary fuel, such as hydrogen fuel, into the combustion chamber. The second nozzle group 42 is configured to inject a pilot agent into the combustion chamber. According to the method of this disclosure, the pilot agent consists of a solution containing hydrogen peroxide.

[0072] Figure 4 An exemplary embodiment of a combustion engine system 10 according to the present disclosure is schematically illustrated. The combustion engine system 10 includes a direct injection compression ignition combustion engine 3 capable of operating using hydrogen fuel. The combustion engine system 10 also includes a control device 100 configured to control the operation of the combustion engine 3 according to the methods described herein. Furthermore, the combustion engine system 10 includes at least one first storage container 12 for hydrogen fuel. The first storage container 12 may be configured, for example, to store hydrogen in compressed or cryogenic compressed form. The first storage container 12 may be in fluid communication with a dual-fuel injector 36 of the combustion engine 3 via a hydrogen delivery line 13.

[0073] The combustion engine system 10 also includes a second storage container 14 configured to store a solution containing hydrogen peroxide. The second storage container is fluidly connected to a dual-fuel injector 36 via a fluid communication line 15. Therefore, the solution can be injected through the same injector used for hydrogen fuel injection, but as a separate pilot injector, through a nozzle dedicated to pilot injector injection. This means that the hydrogen peroxide-containing solution will not mix with the hydrogen fuel until it is present in the combustion chamber of the combustion engine.

[0074] The combustion engine system 10 may optionally also include a concentration regulating device 16. As shown, the concentration regulating device 16 (if present) is arranged in a fluid communication line 15 between the second storage container 14 and the combustion engine 3. The concentration regulating device is configured to adjust the concentration of hydrogen peroxide in the solution flowing through the fluid communication line 15. The concentration regulating device 16 may optionally be controlled by a control device 100.

[0075] Figure 5A flowchart illustrating the method described herein for operating a hydrogen direct injection compression ignition engine is shown schematically. The method includes step S101, which involves injecting a pilot agent into the combustion chamber of the engine to promote the auto-ignition of hydrogen fuel. The pilot agent consists of a solution containing hydrogen peroxide. The method also includes step S102, which involves injecting hydrogen fuel. Step S101 may be initiated appropriately before step S102. Furthermore, step S101 may be terminated before, simultaneously with, or after step S102. The method ends at the end of the combustion stroke of the engine, but may be repeated after the intake stroke of the engine.

[0076] Figure 6 An exemplary embodiment of the device 500 is illustrated schematically. The control device 100 described above may, for example, include, be composed of, or be included in the device 500.

[0077] Device 500 includes non-volatile memory 520, a data processing unit 510, and read / write memory 550. The non-volatile memory 520 has a first memory element 530 in which computer programs, such as an operating system, are stored for controlling the functions of device 500. Device 500 also includes a bus controller, a serial communication port, I / O devices, an A / D converter, a time and date input and transmission unit, an event counter, and an interrupt controller (not depicted). The non-volatile memory 520 also has a second memory element 540.

[0078] A computer program P is provided, comprising instructions for operating a hydrogen direct injection compression ignition (HICI) engine. The engine includes a cylinder and a piston configured to reciprocate within the cylinder and connected to a rotatable crankshaft. The cylinder and piston, together with a cylinder head, form a combustion chamber. The computer program includes instructions for injecting a pilot agent into the combustion chamber to promote the auto-ignition of hydrogen fuel, wherein the pilot agent comprises a solution containing hydrogen peroxide. The computer program may also include instructions for injecting hydrogen fuel into the combustion chamber.

[0079] Program P can be stored in memory 560 and / or read / write memory 550 in executable or compressed form.

[0080] The data processing unit 510 can perform one or more functions, that is, the data processing unit 510 can implement a part of the program P stored in the memory 560 or a part of the program P stored in the read / write memory 550.

[0081] Data processing device 510 can communicate with data port 599 via data bus 515. Non-volatile memory 520 is intended to communicate with data processing unit 510 via data bus 512. Separate memory 560 is intended to communicate with data processing unit 510 via data bus 511. Read / write memory 550 is adapted to communicate with data processing unit 510 via data bus 514. Communication between components can be achieved through communication links. Communication links can be physical connections (such as optoelectronic communication lines) or non-physical connections (such as wireless connections, such as radio links or microwave links).

[0082] When data is received on data port 599, it can be temporarily stored in the second memory element 540. Once the received input data has been temporarily stored, the data processing unit 510 is ready to execute the code as described above.

[0083] Part of the methods described herein can be implemented by the device 500 through a data processing unit 510 that runs a program stored in memory 560 or read / write memory 550. When the device 500 runs the program, the methods described herein are executed.

Claims

1. A method for operating a hydrogen direct injection compression ignition engine (3), The combustion engine (3) includes: Cylinder (30); Piston (31), which is configured to reciprocate within the cylinder (30) and is connected to a rotatable crankshaft (32); The cylinder (30) and the piston (31) together with the cylinder head (34) form a combustion chamber (35); The method includes the following steps: A pilot agent is injected (S101) into the combustion chamber (35) to promote the auto-ignition of the hydrogen fuel. The lead agent is composed of a solution containing hydrogen peroxide.

2. The method according to claim 1, wherein the solution containing hydrogen peroxide is an aqueous solution.

3. The method according to any one of claims 1 or 2, wherein the injection of the pilot agent is initiated at a crankshaft angle less than 30° prior to the crankshaft angle at which the hydrogen fuel injection is initiated; preferably, it is initiated at a crankshaft angle equal to or less than 20° prior to the crankshaft angle at which the hydrogen fuel injection is initiated.

4. The method according to any one of the preceding claims, wherein the pilot agent is injected during a time period corresponding to a crankshaft angle difference of 20° or less; preferably, it is injected during a time period corresponding to a crankshaft angle difference of 10° or less.

5. The method according to any one of the preceding claims, wherein the concentration of hydrogen peroxide in the solution is at least 5% by weight; preferably at least 10% by weight.

6. The method according to any one of the preceding claims, wherein the concentration of hydrogen peroxide in the solution is at most 60% by weight; preferably at most 50% by weight.

7. The method according to any one of the preceding claims, wherein the combustion engine (3) is operated such that the temperature in the combustion chamber (35) is 800K to 1100K; preferably 900K to 1050K.

8. The method according to any one of the preceding claims, wherein the pilot agent is injected by using a dual-fuel injector (36) configured to inject the pilot agent and hydrogen fuel into the combustion chamber (35), respectively.

9. The method according to any one of the preceding claims, wherein the spontaneous combustion of the hydrogen fuel is performed in the presence of a catalyst.

10. A computer program comprising instructions that, when executed by a computer, cause the computer to perform the method according to any one of the preceding claims.

11. A computer-readable medium comprising instructions that, when executed by a computer, cause the computer to perform the method according to any one of claims 1 to 9.

12. A control device (100) configured to control the operation of a hydrogen direct injection compression ignition engine (3), The combustion engine (3) includes: Cylinder (30); Piston (31), which is configured to reciprocate within the cylinder (30) and is connected to a rotatable crankshaft (32); The cylinder (30) and the piston (31) together with the cylinder head (34) form a combustion chamber (35); The control device (100) is configured to: A pilot agent is injected into the combustion chamber (35) to promote the auto-ignition of the hydrogen fuel. The lead agent is composed of a solution containing hydrogen peroxide.

13. The control device (100) according to claim 12, wherein the control device (100) is configured to initiate the injection of the pilot agent at a crankshaft angle of less than 30° prior to the crankshaft angle at which the hydrogen fuel injection is initiated.

14. A combustion engine system (10), said combustion engine system comprising: A direct injection compression ignition combustion engine (3), which is capable of operating using hydrogen fuel; as well as The control device (100) according to any one of claims 12 and 13.

15. The combustion engine system (10) according to claim 14, wherein the combustion engine (3) includes a dual-fuel injector (36) configured to inject a pilot agent and hydrogen fuel into the combustion chamber (35) of the combustion engine (3), respectively.

16. The combustion engine system (10) according to any one of claims 14 and 15, wherein the combustion engine system further comprises: A storage container (14) configured to store a solution containing hydrogen peroxide, the storage container (14) being fluidly connected to an injector (36) via a fluid communication line (15), the injector (36) being configured to inject at least a pilot agent into the combustion chamber (35) of the combustion engine (3); as well as Optionally, a concentration regulating device (16) is provided in the fluid communication line (15) and configured to regulate the concentration of hydrogen peroxide in the solution flowing through the fluid communication line (15).

17. The combustion engine system (10) according to any one of claims 14 to 16, the combustion engine system further comprising a catalyst disposed in the combustion chamber (35).

18. A vehicle (1) comprising a combustion engine system (10) according to any one of claims 14 to 17.

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