Vector jet flow hydrogen injection system of hydrogen internal combustion engine

Abstract

The invention discloses a vector jet flow hydrogen spraying system of a hydrogen internal combustion engine and a spraying method. The vector jet flow hydrogen spraying system comprises a hydrogen spraying device and a hydrogen guide pipe assembly communicating with the hydrogen spraying device. The hydrogen guide pipe assembly comprises a guide pipe communicated with a hydrogen spraying device, a rotating table rotationally connected with the guide pipe, a sleeve fixedly connected with the rotating table and a flexible spraying pipe slidably connected with the sleeve. Wherein the rotating table is fixedly connected with a tensioning structure, the flexible spraying pipe is driven to bend and stretch out and draw back through the combined action of rotation of the rotating table and the tensioning structure, and then free adjustment of the hydrogen jet flow vector by the hydrogen guide pipe assembly is achieved. According to the invention, all-directional hydrogen jet flow vector adjustment is realized, the hydrogen jet flow vector is dynamically adjusted, and abnormal combustion phenomena such as knocking and the like are controlled.

Description

Technical Field

[0001] This invention relates to the technical field of engines, and in particular to a vector jet hydrogen injection system for a hydrogen internal combustion engine. Background Technology

[0002] Abnormal combustion phenomena in hydrogen internal combustion engines mainly include pre-ignition, backfire, and knock. Pre-ignition refers to the phenomenon where fresh charge comes into contact with hot spots in the combustion chamber before being ignited by the spark plug, causing combustion. During the intake process, if the intake valve is not yet closed, the air-fuel mixture in the cylinder may be ignited by hot spots without being sparked by the spark plug, and the flame may propagate into the intake manifold; this abnormal combustion phenomenon is called backfire. Knock refers to the phenomenon where the air-fuel mixture at the end of the combustion chamber ignites spontaneously due to excessively high local temperature and pressure before the flame front arrives, resulting in violent pressure fluctuations. Pre-ignition, backfire, and knock can all seriously affect the normal operation of a hydrogen internal combustion engine, leading to abnormal power output, reduced thermal efficiency, and even destructive consequences for engine components.

[0003] There is a close relationship between the intake system and abnormal combustion in hydrogen internal combustion engines. Optimized design of the hydrogen injection system can significantly improve the hydrogen-air mixing performance of intake manifold-injected hydrogen internal combustion engines. Factors affecting hydrogen-air mixing typically include airflow within the intake manifold and the hydrogen injection position within the manifold. Therefore, for different operating conditions of hydrogen internal combustion engines (airflow field within the intake manifold), controlling the geometry of the hydrogen duct in the hydrogen injection system and adjusting the hydrogen jet vector to promote uniform hydrogen-air mixing can be a key link and important path to solving abnormal combustion problems in hydrogen engines and promoting the development of hydrogen power technology.

[0004] Patent 202510434957.5 discloses a device for suppressing backfire in a hydrogen-injected compression ignition internal combustion engine. The device involves an inclined hydrogen injector facing the intake valve within the intake manifold. A flow-blocking device is located below the nozzle of the hydrogen injector, and an intake gap is formed between the bottom of the flow-blocking device and the bottom of the intake manifold. By placing the flow-blocking device below the hydrogen injector, the risk of backfire caused by high-temperature exhaust gas flowing back into the intake manifold is effectively reduced. However, the hydrogen injector described in this patent has a conventional structure, and while the flow-blocking device suppresses backfire, it does not promote the uniform mixing of hydrogen and air.

[0005] Patent 202410908946.1 discloses a hydrogen injection control method, device, equipment, storage medium, and computer program for a hydrogen injector. The method involves obtaining a target total hydrogen injection volume based on engine operating conditions; obtaining the hydrogen injection quantity and number of injections per cycle based on the target total hydrogen injection volume and a preset hydrogen injection MAP control chart; and controlling the hydrogen injection from the hydrogen injector based on the hydrogen injection quantity and the number of injections per cycle. By obtaining optimal hydrogen injection parameters through engine operating conditions, the target total hydrogen injection volume, and the preset hydrogen injection MAP control chart, hydrogen is injected using a low-pressure, multiple-injection method, which maintains a constant total hydrogen injection volume under current operating conditions while reducing startup noise caused by hydrogen injection. This patent focuses on the control method of a hydrogen injector, primarily aiming to control the injection quantity. It does not improve the main structure of the injector and does not contribute to improving the uniform mixing of hydrogen and air.

[0006] Patent 202410794064.7 discloses a hydrogen injector and an internal combustion engine. The hydrogen injector includes a valve body, a needle valve assembly, a variable stiffness elastic element, and a coil. This invention is mainly designed to improve the responsiveness and sealing performance of the product and extend its service life. However, the main structure of the injector remains unchanged, and it does not promote the uniform mixing of hydrogen and air.

[0007] Patent 202410655162.2 discloses a hydrogen injection control method, device, electronic equipment, and storage medium for a hydrogen engine. Based on real-time monitored operating data of the hydrogen engine, it determines the engine's operating parameters; based on these parameters, it determines the relative intake air volume, excess air demand coefficient, and correction coefficient for the excess air demand coefficient entering the engine cylinder; based on the operating parameters and relative intake air volume, it determines the hydrogen injection angle; based on the relative intake air volume, excess air demand coefficient, and correction coefficient, it determines the relative hydrogen injection quantity; based on a pre-determined hydrogen injection pulse width correction coefficient and injector characteristic correction coefficient, combined with the relative hydrogen injection quantity, it determines the hydrogen injection pulse width; and it performs hydrogen injection control based on the hydrogen injection pulse width and injection angle. This invention can improve the accuracy of hydrogen injection control in a hydrogen engine. However, the "hydrogen injection angle" mentioned in this patent refers to the hydrogen injection phase concept, corresponding to a physical concept of time. This patent does not address the spatial angle of hydrogen injection and does not contribute to improving the uniform mixing of hydrogen and air. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a hydrogen internal combustion engine vector jet hydrogen injection system that can adjust the hydrogen jet vector according to the operating conditions of the hydrogen internal combustion engine, ensuring that the hydrogen-air mixing characteristics in the intake manifold are optimal under all operating conditions. During actual operation of the hydrogen internal combustion engine, a control method for the hydrogen internal combustion engine vector jet hydrogen injection system improves combustion stability and suppresses knocking tendency. To achieve the above-mentioned objectives and other advantages of the present invention, a hydrogen internal combustion engine vector jet hydrogen injection system is provided, comprising: Hydrogen injector and hydrogen conduit assembly connected to the hydrogen injector; The hydrogen conduit assembly includes a conduit connected to a hydrogen injector, a rotary table rotatably connected to the conduit, a sleeve fixedly connected to the rotary table, and a flexible nozzle slidably connected to the sleeve. The rotating platform is fixedly equipped with a tensioning structure. The rotation of the rotating platform and the tensioning structure work together to drive the flexible nozzle to bend and extend, thereby realizing the free adjustment of the hydrogen jet vector of the hydrogen conduit assembly.

[0009] Preferably, a circular rotation zone is formed inside the end of the rotating platform near the conduit.

[0010] Preferably, a fixed wheel is fixedly connected to one end of the conduit near the rotating platform, and the fixed wheel matches the circular rotation range.

[0011] Preferably, the tensioning structure includes a tensioning wheel and a string fixedly connected to the tensioning wheel, with one end of the string away from the tensioning wheel fixedly connected to the flexible nozzle.

[0012] A method for injecting hydrogen via vector jet at calibration time in a hydrogen internal combustion engine includes: when the hydrogen internal combustion engine is operating under a certain operating condition, by traversing the allowable jet vector strategies under that operating condition, finding the jet vector that minimizes the variation in the in-cylinder combustion cycle of the hydrogen internal combustion engine, and adding the operating condition to the optimal jet vector set for each operating condition of the hydrogen internal combustion engine. S opt After the hydrogen internal combustion engine has completed all operating conditions, a hydrogen jet vector pulse spectrum is formed. S opt 。

[0013] A method for injecting hydrogen via vector jet in a hydrogen internal combustion engine during actual engine operation includes: identifying the operating conditions of the hydrogen internal combustion engine; and, upon entering a steady-state operating condition, adjusting the hydrogen jet vector pulse spectrum. S optThe hydrogen internal combustion engine reads the hydrogen jet vector strategy based on the current operating conditions, and then executes this injection strategy by changing the operating state of the flexible nozzle. Based on the knock sensor signal of the hydrogen internal combustion engine, when knocking occurs, the strategy is adjusted near the current jet vector. S opt-T And try pressing S opt-T Control the hydrogen internal combustion engine's vector jet hydrogen injection system to inject hydrogen; if knocking still occurs, continue to try changing the injection method. S opt-T To eliminate the knocking shock.

[0014] Preferably, a hydrogen internal combustion engine vector jet hydrogen injection system and a corresponding calibration and control strategy are provided. The hydrogen internal combustion engine vector jet hydrogen injection system includes a hydrogen injector and a variable-structure hydrogen duct assembly. The hydrogen duct assembly achieves extension, rotation, and bending functions through its various components. Through a combination of these three motion modes, the hydrogen jet vector can be adjusted within a certain range. A control method for the hydrogen internal combustion engine vector jet hydrogen injection system identifies the operating conditions of the hydrogen internal combustion engine, determines the hydrogen jet vector most favorable for uniform mixing of hydrogen and air in the intake manifold, and sequentially controls the geometric changes of the hydrogen injection system.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are: 1) Achieve omnidirectional hydrogen jet vector adjustment through combinations and changes in the hydrogen injection duct structure; 2) Adjust the adaptive jet vector according to the operating conditions of the hydrogen internal combustion engine; 3) By monitoring the operation of the hydrogen internal combustion engine in real time, the hydrogen jet vector is dynamically adjusted to control abnormal combustion phenomena such as knocking. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural schematic diagram of the hydrogen internal combustion engine vector jet hydrogen injection system according to the present invention; Figure 2 A structural diagram of the hydrogen duct assembly of the hydrogen internal combustion engine vector jet hydrogen injection system according to the present invention; Figure 3 A structural diagram of the hydrogen duct assembly in the contracted state of the black extension module of the hydrogen internal combustion engine vector jet hydrogen injection system according to the present invention. Figure 4 This is a schematic diagram of the intermediate state structure of the hydrogen duct assembly of the hydrogen internal combustion engine vector jet hydrogen injection system according to the present invention. Figure 5 A schematic diagram of the hydrogen duct assembly in the contracted state of the hydrogen internal combustion engine vector jet hydrogen injection system according to the present invention. Figure 6A flow chart of the hydrogen injection system for a hydrogen internal combustion engine vector jet according to the present invention during calibration; Figure 7 This is a flow chart illustrating the injection process of the hydrogen internal combustion engine vector jet hydrogen injection system according to the present invention during actual engine operation. Detailed Embodiments The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Reference Figure 1-2 A hydrogen internal combustion engine vector jet hydrogen injection system, comprising: Hydrogen injector 101 and hydrogen conduit assembly 102 connected to the hydrogen injector 101; The hydrogen conduit assembly 102 includes a conduit 201 connected to a hydrogen injector 101, a rotating platform 202 rotatably connected to the conduit 201, a sleeve 203 fixedly connected to the rotating platform 202, and a flexible nozzle 205 slidably connected to the sleeve 203. A circular rotation range is formed inside the rotating platform 202 near the conduit 201. A fixed wheel is fixedly connected to the end of the conduit 201 near the rotating platform 202. The fixed wheel matches the circular rotation range, so that when the rotating platform 202 rotates, the rotating platform 202 and the conduit 201 are in a state of relative rotation.

[0018] In one embodiment, a tensioning structure is fixedly connected to the rotary table 202. The tensioning structure includes a tensioning wheel and a string 204 fixedly connected to the tensioning wheel. The end of the string 204 away from the tensioning wheel is fixedly connected to the flexible nozzle 205. The rotation of the rotary table 202 and the combined action of the tensioning structure drive the flexible nozzle 205 to bend and extend, thereby enabling the hydrogen conduit assembly 102 to freely adjust the hydrogen jet vector.

[0019] like Figure 3 As shown, when the system is in the contracted state, the tensioning structure is in the relaxed state. At this time, the flexible nozzle 205 is retracted inside the sleeve 203 and is not pulled by the tensioning wheel, remaining in a naturally straight state. The rotary table 202 does not rotate.

[0020] like Figure 4 As shown, the system is in an intermediate state, where the tensioning structure is relaxed and the flexible nozzle 205 is not pulled by the tensioning wheel, remaining in a naturally straight state. The flexible nozzle 205 moves away from the rotary table 202 along the length of the sleeve 203.

[0021] like Figure 5 As shown, the system is in a rotating and bending state. At this time, by rotating the tension wheel, the string 204 is tightened, causing the flexible nozzle 205 near the string 204 to bend under tension. The rotating platform 202 rotates relative to the conduit 201, allowing the flexible nozzle 205 and sleeve 203 located on the rotating platform 202 to rotate relative to the conduit 201. This allows for free adjustment of the hydrogen jet vector in the hydrogen conduit. In actual operation, the rotating platform 202 is connected to the conduit 201, and the sleeve 203 can rotate relative to the conduit 201. The sleeve 203 is fixedly connected to the rotating platform 202. The flexible nozzle 205 is installed inside the sleeve 203 and can slide along a track within the sleeve 203. The rotating platform 202 has a tensioning mechanism, which can change the state of the flexible nozzle 205 by tightening / relaxing the string 204.

[0022] One embodiment, such as Figure 6 As shown, a method for injecting hydrogen via vector jet at calibration time in a hydrogen internal combustion engine includes: when the hydrogen internal combustion engine is operating under a certain condition, by traversing the allowable jet vector strategies under that condition, finding the jet vector that minimizes the variation in the in-cylinder combustion cycle of the hydrogen internal combustion engine, and marking this condition and adding it to the optimal jet vector set for each operating condition of the hydrogen internal combustion engine. S opt After the hydrogen internal combustion engine has completed all operating conditions, a hydrogen jet vector pulse spectrum is formed. S opt 。

[0023] The specific process is as follows: When the hydrogen internal combustion engine is started, variable i is assigned the value 1, and variable m is assigned the number of elements in set C (the hydrogen internal combustion engine operating condition set). When i ≤ m, variable j is assigned the value 1, and variable n is assigned the number of elements in set S (the jet vector set of the hydrogen internal combustion engine adaptive jet vector hydrogen injection system). Variable Cov... min Assign a value of 1 to (the cyclical variation of the hydrogen internal combustion engine) and create an empty set S. opt This is used to store the optimal jet vector strategy; otherwise, the system shuts down. When j≤n, the jet vector strategy S in the jet vector set of the hydrogen internal combustion engine adaptive jet vector hydrogen injection system is selected. ij Otherwise, increment the value of variable i by 1 and re-evaluate the relationship between i and m. When using the jet vector strategy S... ij If no detonation occurs, then the jet vector strategy S will be applied. ij Corresponding Cycle Variation Cov of Hydrogen Internal Combustion Engine ij With Cov min Compare the values; otherwise, increment variable j by 1 and re-evaluate the relationship between j and n. If Cov ij <Cov min, will Cov ij Assigned to Cov min And the jet vector strategy S ij Add to collection S opt (Optimal jet vector set for various operating conditions of hydrogen internal combustion engine) S opt Otherwise, increment variable j by 1 and re-evaluate the relationship between j and n.

[0024] One embodiment, such as Figure 7 As shown, a method for injecting hydrogen using a vector jet in a hydrogen internal combustion engine during actual engine operation includes: identifying the operating conditions of the hydrogen internal combustion engine; and, upon entering a steady-state operating condition, injecting hydrogen into the hydrogen jet vector pulse spectrum. S opt The hydrogen jet vector strategy is read based on the current operating conditions. S opti Furthermore, the hydrogen internal combustion engine vector jet hydrogen injection system executes this injection strategy by changing the operating state of the flexible nozzle (205); based on the knock sensor signal of the hydrogen internal combustion engine, when knock occurs, the strategy is adjusted near the current jet vector. S opt-T And try pressing S opt-T Control the hydrogen internal combustion engine's vector jet hydrogen injection system to inject hydrogen; if knocking still occurs, continue to try changing the injection method. S opt-T To eliminate detonation. The number of devices and processing scale described herein are for simplification of the invention; applications, modifications, and variations of the invention will be apparent to those skilled in the art. Although embodiments of the invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the invention, and further modifications can be readily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A hydrogen internal combustion engine vector jet hydrogen injection system, characterized in that, include: Hydrogen injector (101) and hydrogen conduit assembly (102) connected to said hydrogen injector (101). The hydrogen conduit assembly (102) includes a conduit (201) connected to a hydrogen injector (101), a rotary table (202) rotatably connected to the conduit (201), a sleeve (203) fixedly connected to the rotary table (202), and a flexible nozzle (205) slidably connected to the sleeve (203). The rotating platform (202) is fixed with a tensioning structure. The rotation of the rotating platform (202) and the tensioning structure work together to drive the flexible nozzle (205) to bend and extend, thereby realizing the free adjustment of the hydrogen jet vector by the hydrogen conduit assembly (102).

2. The hydrogen internal combustion engine vector jet hydrogen injection system as described in claim 1, characterized in that, The rotating stage (202) has a circular rotation area inside the end near the conduit (201).

3. The hydrogen internal combustion engine vector jet hydrogen injection system as described in claim 2, characterized in that, A fixed wheel is fixedly connected to one end of the conduit (201) near the rotating platform (202), and the fixed wheel matches the circular rotation range.

4. The hydrogen internal combustion engine vector jet hydrogen injection system as described in claim 1, characterized in that, The tensioning structure includes a tensioning wheel and a string (204) fixed to the tensioning wheel, with one end of the string (204) away from the tensioning wheel fixed to a flexible nozzle (205).

5. A method for injecting hydrogen into a hydrogen internal combustion engine during calibration using a hydrogen vector jet injection system as described in any of claims 1-4, characterized in that, include: When the hydrogen internal combustion engine is operating under a certain condition, by iterating through the allowable jet vector strategies under that condition, the jet vector that minimizes the variation in the in-cylinder combustion cycle of the hydrogen internal combustion engine is found, and this operating condition is marked and added to the optimal jet vector set for all operating conditions of the hydrogen internal combustion engine. S opt After the hydrogen internal combustion engine has completed all operating conditions, a hydrogen jet vector pulse spectrum is formed. S opt 。 6. A method for injecting hydrogen into a hydrogen internal combustion engine during actual engine operation using a hydrogen vector jet hydrogen injection system as described in any of claims 1-4, characterized in that, include: The operating condition of the hydrogen internal combustion engine is identified. Once it enters a steady-state operating condition, the hydrogen jet vector pulse spectrum is used for identification. S opt The hydrogen jet vector strategy is read based on the current operating conditions, and then the hydrogen internal combustion engine vector jet hydrogen injection system executes this injection strategy by changing the operating state of the flexible nozzle (205); based on the knock sensor signal of the hydrogen internal combustion engine, when knock occurs, the strategy is adjusted near the current jet vector. S opt-T And try pressing S opt-T Control the hydrogen internal combustion engine's vector jet hydrogen injection system to inject hydrogen; if knocking still occurs, continue to try changing the injection method. S opt-T To eliminate the knocking shock.

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