Crankcase ventilation system of hydrogen engine

Abstract

The invention discloses a crankcase ventilation system of a hydrogen engine, and relates to the technical field of vehicles, the crankcase ventilation system of the hydrogen engine comprises a crankcase, a combustion chamber, an oil-gas separator, a hydrogen conveying device and a ventilation structure, the hydrogen conveying device comprises a hydrogen tank and a first flow path communicated with the hydrogen tank, the first flow path is communicated with the combustion chamber and conveys gas in a hydrogen tank into the combustion chamber for combustion; the ventilation structure is provided with a second flow path, and the second flow path communicates with the first flow path and the oil-gas separator, so that mixed gas which is output by the oil-gas separator and contains water vapor can be conveyed into the combustion chamber together with hydrogen to be combusted; therefore, the problem that when the engine temperature is low, water vapor generated by hydrogen combustion is condensed into liquid water and enters oil pan engine oil to cause engine oil emulsification is solved.

Description

Technical Field

[0001] The invention relates to the technical field of vehicles, and in particular to a crankcase ventilation system for a hydrogen engine. Background Art

[0002] At present, major OEMs are competing to develop hydrogen engines. Hydrogen engines only produce water when burned, so they are a clean energy engine. In addition, existing gasoline engines can be adapted to hydrogen fuel by making adaptive changes.

[0003] However, since hydrogen is used as fuel, the combustion of hydrogen produces a large amount of water vapor. When the engine is cold-started, due to the low oil temperature, water temperature and engine body temperature, the water vapor condenses into liquid water and enters the oil in the oil pan, causing the oil to emulsify. Summary of the invention

[0004] The main purpose of the present invention is to provide a hydrogen engine crankcase ventilation system, aiming to provide a hydrogen engine crankcase ventilation system that prevents liquid water from entering the oil in the oil pan and causing oil emulsification.

[0005] To achieve the above object, the present invention provides a hydrogen engine crankcase ventilation system, the hydrogen engine crankcase ventilation system comprising a crankcase, a combustion chamber and an oil-gas separator, the hydrogen engine crankcase ventilation system also comprising:

[0006] A hydrogen delivery device, comprising a hydrogen tank and a first flow path connected to the hydrogen tank, wherein the first flow path is connected to the combustion chamber; and

[0007] The ventilation structure has a second flow path, and the second flow path is connected to the first flow path and the oil-gas separator, so that the mixed gas output by the oil-gas separator can be transported to the combustion chamber for combustion together with the hydrogen.

[0008] In one embodiment, a portion of the first flow path connected to the second flow path forms a connection, and a cross-sectional area of ​​the connection is smaller than a cross-sectional area of ​​the remaining portion of the first flow path.

[0009] In one embodiment, the first flow path further includes a first hydrogen transmission flow path and a second hydrogen transmission flow path, the first hydrogen transmission flow path and the second hydrogen transmission flow path are both connected to the connection and are disposed on both sides of the connection, wherein:

[0010] The first hydrogen transmission flow path comprises a first cavity section and a second cavity section which are connected to each other, the first cavity section is connected to the hydrogen tank, the second cavity section is connected to the connection, and the diameter of the second cavity section gradually decreases along the direction from the hydrogen tank to the connection;

[0011] The second hydrogen supply flow path is connected to the combustion chamber, and the second hydrogen supply flow path includes a third cavity segment and a fourth cavity segment that are connected to each other. The third cavity segment is connected to the connection point, and the fourth cavity segment is connected to the combustion chamber. The diameter of the third cavity segment gradually decreases along the direction from the combustion chamber to the connection point.

[0012] In one embodiment, the diameter of the first cavity segment is D1, the diameter of the connection is D2, and the diameter of the fourth cavity segment is D3, then:

[0013] D1:D2 is (3-4):1; and / or,

[0014] D3:D2 is (3~4):1.

[0015] In one embodiment, a pressure reducing valve is disposed on the first cavity section.

[0016] In one embodiment, the hydrogen delivery device further comprises:

[0017] A connecting member, the connecting member having a receiving cavity; and

[0018] a nozzle, disposed outside the connecting member and connected to the accommodating chamber, the nozzle being connected to the combustion chamber to spray the gas in the accommodating chamber into the combustion chamber;

[0019] Wherein, the fourth cavity section includes the accommodating cavity and the nozzle.

[0020] In one embodiment, the nozzle is provided in plurality.

[0021] In one embodiment, a control valve is provided on the second flow path.

[0022] In one embodiment, the hydrogen engine crankcase ventilation system further includes an air filter device, a supercharger, an intercooler, an intake manifold connected to the engine intake pipeline, and a passage structure, wherein the passage structure includes:

[0023] An intake passage, the two ends of which are connected to the air filter device and the intake manifold respectively, including a rear pipeline of the air filter, a rear pipeline of the supercharger and a rear pipeline of the intercooler connected in sequence, and a throttle valve is arranged on the rear pipeline of the intercooler;

[0024] A first tortuous passage, the first tortuous passage is a gas passage under a light load condition, two ends of the first tortuous passage are respectively connected to the oil-gas separator and the intake manifold, and a first one-way valve is provided on the first tortuous passage;

[0025] A second tortuous passage, the second tortuous passage is parallel to the first tortuous passage and is a gas passage under heavy load conditions, the two ends of the second tortuous passage are respectively connected to the oil-gas separator and the pipeline after the air filter, and a second one-way valve is provided on the second tortuous passage; and

[0026] An air supply passage, two ends of which are respectively connected to the air filter post-pipeline and the crankcase, and a third one-way valve is provided on the air supply passage.

[0027] In one embodiment, the passage structure further includes a pressure relief pipeline, two ends of which are respectively connected to the air filter rear pipeline and the intercooler rear pipeline, and a pressure relief valve is provided on the pressure relief pipeline.

[0028] In the technical solution of the present invention, the hydrogen in the hydrogen tank is transported to the combustion chamber for combustion by setting a first flow path, and the mixed gas output by the oil-gas separator can be transported to the combustion chamber via the first flow path for combustion by setting a second flow path connecting the oil-gas separator and the first flow path. At low temperatures, when a large amount of water vapor in the combustion exhaust gas stays in the low-temperature crankcase, the combustion exhaust gas in the crankcase can be extracted through the second flow path to prevent the water vapor in the crankcase from condensing into liquid water and entering the oil pan to cause the oil to emulsify. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0030] Figure 1 A schematic structural diagram of an embodiment of a crankcase ventilation system for a hydrogen engine provided by the present invention;

[0031] Figure 2 for Figure 1 Schematic diagram of the structure of the first flow path.

[0032] Description of Figure Numbers:

[0033] 100. Crankcase ventilation system of hydrogen engine; 1. Crankcase; 2. Oil-gas separator; 3. Hydrogen delivery device; 31. Hydrogen tank; 32. First flow path; 321. Connection; 322. First cavity section; 323. Second cavity section; 324. Third cavity section; 325. Fourth cavity section; 33. Pressure reducing valve; 34. Connector; 35. Nozzle; 4. Ventilation structure; 41. Second flow path; 42. Control valve; 5. Passage structure; 51. Intake passage; 511. Pipeline after air filter; 512. Pipeline after supercharger; 513. Pipeline after intercooler; 52. First tortuous passage; 53. Second tortuous passage; 54. Air supply passage; 55. Pressure relief pipeline; 6. Pressure relief valve; a. Air filter device; b. Supercharger; c. Intercooler; d. Intake manifold; e. Throttle valve.

[0034] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0037] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0038] When a vehicle is driving in a cold area, it is in a low temperature environment. When the engine is running at a low load, the piston leakage is relatively low, and the water vapor entering the crankcase through the piston leakage is relatively small. At this time, the negative pressure of the engine intake manifold is relatively large. The combustion exhaust gas in the crankcase is drawn into the intake manifold through the low load path and finally enters the combustion chamber and is burned. Since the negative pressure of the intake manifold is large at low load, the exhaust gas extraction effect in the crankcase is better, and the piston leakage is also low at low load, so only a small amount of water vapor condenses into the engine oil in the end; however, when the vehicle is in a low temperature environment and the engine is running at high load, the piston leakage is large, and more combustion exhaust gas enters the crankcase through piston leakage. At this time, due to the pressurization effect of the supercharger, the intake manifold is at a large positive pressure, and the exhaust gas in the crankcase can only be extracted through the high load path. Since the negative pressure after the air filter is small, the gas extraction effect in the crankcase is poor, resulting in a large amount of water vapor in the combustion exhaust gas staying in the low-temperature crankcase for a long time. In addition, since the body temperature, oil temperature and water temperature are all low during cold start, the water vapor condenses into liquid water when it is cold and enters the oil in the oil pan, causing serious emulsification of the engine oil.

[0039] The present invention proposes a hydrogen engine crankcase ventilation system 100, which can extract water vapor in the crankcase 1 to avoid oil emulsification when the vehicle is in a low temperature environment and the engine is running at a high load.

[0040] Figure 1 A schematic structural diagram of an embodiment of a crankcase ventilation system for a hydrogen engine provided by the present invention; Figure 2 for Figure 1 Schematic diagram of the structure of the first flow path.

[0041] See also Figure 1 and Figure 2 In one embodiment of the present invention, the hydrogen engine crankcase ventilation system 100 includes a crankcase 1, a combustion chamber, an oil-gas separator 2, a hydrogen delivery device 3 and a ventilation structure 4, the hydrogen delivery device 3 includes a hydrogen tank 31 and a first flow path 32 connected to the hydrogen tank 31, the first flow path 32 is connected to the combustion chamber; the ventilation structure 4 has a second flow path 41, the second flow path 41 is connected to the first flow path 32 and the oil-gas separator 2, so that the mixed gas output by the oil-gas separator 2 can be delivered to the combustion chamber together with the hydrogen for combustion.

[0042] In the technical solution of the present invention, the hydrogen in the hydrogen tank 31 is transported to the combustion chamber for combustion by providing the first flow path 32, and the mixed gas output by the oil-gas separator 2 can be transported to the combustion chamber for combustion via the first flow path 32 by providing the second flow path 41 connecting the oil-gas separator 2 and the first flow path 32. At low temperatures, when a large amount of water vapor in the combustion exhaust gas stays in the low-temperature crankcase 1, the combustion exhaust gas in the crankcase 1 can be extracted through the second flow path 41 to prevent the water vapor in the crankcase 1 from condensing into liquid water and entering the oil pan oil, causing the oil to emulsify.

[0043] It should be noted that a boost valve may be provided on the second flow path 41 to deliver the mixed gas in the second flow path 41 to the first flow path 32; and the mixed gas in the second flow path 41 may also be delivered to the first flow path 32 through the pipeline structure design of the first flow path 32. In one embodiment, in the first flow path 32, the portion connected to the second flow path 41 forms a connection 321, and the cross-sectional area of ​​the connection 321 is smaller than the cross-sectional area of ​​the rest of the first flow path 32. In the first flow path 32, the cross-sectional area of ​​the connection 321 and its short sections before and after present a process of changing from large to small and then from small to large. When the gas passes through a variable diameter pipe, since the mass of the fluid passing through any cross section of the pipe per unit time is the same, the flow rate is inversely proportional to the square of the pipe diameter (cross-sectional area). Therefore, when the pipe diameter (cross-sectional area) becomes smaller, the flow rate increases; when the pipe diameter (cross-sectional area) becomes larger, the flow rate decreases. According to the Bernoulli equation, when the flow rate increases, the pressure decreases; when the flow rate decreases, the pressure increases. Therefore, when the gas reaches the connection 321 , the cross-sectional area decreases and the flow rate increases. At this time, the pressure at the connection 321 is relatively small. The second flow path 41 is connected to the connection 321 , and the smaller pressure causes the gas in the second flow path 41 to be transported to the first flow path 32 .

[0044] When hydrogen is injected into the cylinder for combustion, the hydrogen in the first flow path 32 will flow, and a large negative pressure will be generated at the connection 321. The combustion exhaust gas in the crankcase 1 is sucked into the first flow path 32 through the negative pressure through the second flow path 41. The combustion exhaust gas in the crankcase 1 contains oil vapor, a large amount of water vapor and other exhaust gases, which are mixed with hydrogen and transported to the combustion chamber for combustion.

[0045] In the embodiments of the present invention, please refer to Figure 1 and Figure 2The first flow path 32 also includes a first hydrogen transmission flow path and a second hydrogen transmission flow path, both of which are connected to the connection 321 and are arranged on both sides of the connection 321, wherein the first hydrogen transmission flow path includes a first cavity section 322 and a second cavity section 323 that are connected to each other, the first cavity section 322 is connected to the hydrogen tank 31, the second cavity section 323 is connected to the connection 321, and the diameter of the second cavity section 323 gradually decreases along the direction from the hydrogen tank 31 to the connection 321; the second hydrogen transmission flow path is connected to the combustion chamber, and the second hydrogen transmission flow path includes a third cavity section 324 and a fourth cavity section 325 that are connected to each other, the third cavity section 324 is connected to the connection 321, and the fourth cavity section 325 is connected to the combustion chamber, and the diameter of the third cavity section 324 gradually decreases along the direction from the combustion chamber to the connection 321. That is, the gas from the hydrogen tank 31 flows through the first cavity section 322, the second cavity section 323, the connection 321, the third cavity section 324, and the fourth cavity section 325 in sequence to reach the combustion chamber. Along the gas flow direction, the diameter of the first cavity section 322 near the second cavity section 323 remains unchanged, the diameter of the second cavity section 323 gradually decreases, the diameter of the second cavity section 323 gradually decreases from the diameter of the first cavity section 322 to the diameter of the connection 321, the diameter of the third cavity section 324 gradually decreases, the diameter of the third cavity section 324 gradually increases from the diameter of the connection 321 to the diameter of the fourth cavity section 325, and the diameter of the fourth cavity section 325 near the third cavity section 324 remains unchanged, forming a venturi-like structure. Wherein, the second cavity section 323 and the third cavity section 324 can respectively include one or more sections of conical tubes.

[0046] Since the diameters of the second cavity section 323 and the third cavity section 324 change gradually, the gas flow rate in the second cavity section 323 and the third cavity section 324 changes gradually, so that the flow of the airflow in the cavity section will be smoother. In some other embodiments, the first flow path 32 can also be set to change directly from the diameter of the first cavity section 322 to the diameter of the connection 321. However, the sudden change in the cavity section diameter may cause airflow turbulence and increased resistance due to a sudden increase or decrease in flow rate, and may also cause the airflow to separate on the inner wall of the pipe, forming vortices or backflows, affecting the ventilation effect. Therefore, the gradual change in the diameter of the second cavity section 323 and the third cavity section 324 can avoid airflow turbulence and increased resistance due to a sudden increase or decrease in flow rate, and can prevent the airflow from generating obvious vortices or turbulence at the place where the pipe diameter changes, thereby reducing airflow resistance and improving ventilation efficiency.

[0047] In the embodiment of the present invention, the diameter of the first cavity section 322 is D1, the diameter of the connection 321 is D2, and the diameter of the fourth cavity section 325 is D3, then: D1: D2 is (3-4): 1;

[0048] D3:D2 is (3-4):1. The above arrangement allows the flow rate and pressure of the gas to change relatively smoothly during the gradual contraction and expansion of the cavity segment, which is beneficial to reducing the pressure head loss and can have a higher gas delivery efficiency. If the diameter ratio of the first cavity segment 322 to the connection 321 is too small, the negative pressure of the connection 321 will be too small. If the diameter ratio of the first cavity segment 322 to the connection 321 is too large, it will cause pressure head loss, affecting the efficiency of gas delivery.

[0049] The first chamber section 322 is provided with a pressure reducing valve 33. The pressure reducing valve 33 can reduce the pressure of the high-pressure hydrogen in the hydrogen tank 31 to the stable pressure range required by the first flow path 32, and can also control the flow rate of hydrogen to a certain extent, so that the hydrogen can be burned more fully in the combustion chamber, thereby improving the utilization efficiency of energy.

[0050] In some specific embodiments, the hydrogen pressure in the hydrogen storage tank is 350-700 bar, which is reduced to 20-50 bar by the pressure reducing valve 33. The hydrogen pressure in the first flow path 32 is about 20 bar. By calculation, a negative pressure (relative pressure) of -50-70 kPa can be generated at the connection 321. The gas pressure in the engine crankcase 1 is generally about -4-0.5 kPa, so the exhaust gas in the crankcase 1 can be very efficiently absorbed through the above structure.

[0051] In addition, the hydrogen delivery device 3 also includes a connector 34 and a nozzle 35, wherein the connector 34 has a receiving chamber, the nozzle 35 is arranged outside the connector 34 and connected to the receiving chamber, and the nozzle 35 is connected to the combustion chamber to spray the gas in the receiving chamber into the combustion chamber; wherein the fourth chamber section 325 includes the receiving chamber and the nozzle 35. Using the nozzle 35 to spray the gas in the receiving chamber into the combustion chamber can not only make the gas in the receiving chamber and the gas in the combustion chamber evenly mixed, which is conducive to the combustion reaction, reducing fuel waste and emissions, but also can accurately control the flow rate of the gas in the receiving chamber, so that the combustion process is more controllable, which helps to improve the combustion efficiency. In other embodiments, direct injection or a hydrogen injection valve or a swirl injector, etc. can also be used to transport the hydrogen in the first flow path 32 to the combustion chamber for combustion.

[0052] In addition, when the second flow path 41 is in operation, the combustion exhaust gas containing water vapor and oil vapor in the crankcase 1 can be drawn into the hydrogen injection nozzle to lubricate the plunger structure in the hydrogen injection nozzle, thereby improving the reliability of the hydrogen injection nozzle.

[0053] Furthermore, the nozzle 35 is provided in plurality. The plurality of nozzles 35 can be arranged on one side or the peripheral side of the accommodating cavity. The use of the plurality of nozzles 35 can more efficiently achieve uniform mixing of the gas in the accommodating cavity and the gas in the combustion chamber.

[0054] When it is not necessary to deliver the mixed gas outputted by the oil-gas separator 2 to the first flow path 32, the connection between the first flow path 32 and the second flow path 41 can be disconnected, or the first flow path 32 can be disconnected. In some embodiments, a control valve 42 is provided on the second flow path 41. The control valve 42 controls the on-off of the second flow path 41, thereby controlling whether the mixed gas outputted by the oil-gas separator 2 can be delivered to the first flow path 32. When the control valve 42 controls the disconnection of the second flow path 41, the mixed gas outputted by the oil-gas separator 2 will not be delivered to the first flow path 32.

[0055] Furthermore, the crankcase ventilation system 100 of the hydrogen engine also includes an air filter device a, a supercharger b, an intercooler c, an intake manifold d connected to the engine intake pipeline, and a passage structure 5, wherein the passage structure 5 includes an intake passage 51, a first tortuous passage 52, a second tortuous passage 53, and an air supply passage 54; the two ends of the intake passage 51 are respectively connected to the air filter device a and the intake manifold d, including an air filter rear pipeline 511, a supercharger rear pipeline 512, and an intercooler rear pipeline 513 connected in sequence, and a throttle valve e is arranged on the intercooler rear pipeline 513; the first tortuous passage 52 is a gas passage under low load conditions, and the two ends of the first tortuous passage 52 are respectively connected to the oil-gas separation 2 and the intake manifold d, the first tortuous passage 52 is provided with a first one-way valve, so that the gas can only flow from the oil-gas separator 2 to the intake manifold d; the second tortuous passage 53 is parallel to the first tortuous passage 52, and is the gas passage under high load conditions, the two ends of the second tortuous passage 53 are respectively connected to the oil-gas separator 2 and the air filter post-pipeline 511, the second tortuous passage 53 is provided with a second one-way valve, so that the gas can only flow from the oil-gas separator 2 to the air filter post-pipeline 511; the two ends of the air supply passage 54 are respectively connected to the air filter post-pipeline 511 and the crankcase 1, and the air supply passage 54 is provided with a third one-way valve, so that the gas can only flow from the air filter post-pipeline 511 to the crankcase 1.

[0056] When the second flow path 41 is disconnected:

[0057] When the engine is running at a low load, the negative pressure in the manifold is relatively large, and the gas in the crankcase 1 is drawn into the intake manifold d through the first crank passage 52, and finally enters the combustion chamber and is burned.

[0058] In order to prevent the negative pressure in the crankcase 1 from being too large, resulting in increased piston leakage and ultimately affecting the engine fuel consumption, an air supply passage 54 is provided. When the negative pressure in the crankcase 1 is large, fresh gas after the air filter is supplemented to the crankcase 1 through the air supply passage 54 to prevent the negative pressure in the crankcase 1 from being too large. A one-way valve is provided in the air supply passage 54 so that the gas can only flow from the pipeline 511 after the air filter to the crankcase 1.

[0059] When the engine is running under high load, the intake manifold is under positive pressure (supercharged engine), the gas in the crankcase 1 cannot be extracted through the first tortuous passage 52, and the air pressure after the air filter is less than the atmospheric pressure. Therefore, the second tortuous passage 53 is provided so that the gas in the crankcase 1 can be extracted to the pipeline 511 after the air filter through the second tortuous passage 53.

[0060] When the vehicle is started in a cold environment:

[0061] When the engine water temperature is low (for example, T≤-10°C) and the engine is running at a low load, the negative pressure of the intake manifold d is relatively large (by monitoring the manifold pressure, when the manifold negative pressure P≤-10kPa (relative pressure)), the second flow path 41 is controlled to be disconnected. After the combustion exhaust gas mixed with water vapor and oil vapor in the crankcase 1 passes through the oil-gas separator 2 to separate the oil, the remaining gas is drawn into the intake manifold d by the larger negative pressure of the manifold, and finally enters the combustion chamber and is burned.

[0062] When the engine water temperature is low (for example, T≤-10℃), and the engine is running at medium and high load, at this time, due to the supercharger b's supercharging effect on the intake system, the intake manifold d has a large positive pressure (which can be achieved by monitoring the manifold pressure, when the manifold pressure P>-10kPa (relative pressure)), and the second flow path 41 is controlled to be connected. At this time, the combustion exhaust gas mixed with water vapor and oil vapor in the crankcase 1 is separated by the oil-gas separator 2, and the remaining gas is extracted into the first flow path 32 by the large negative pressure at the connection 321 and mixed with the hydrogen in the first flow path 32 and then transported to the combustion chamber for combustion. Moreover, since both the large load path and the small load path of the crankcase 1 are arranged with a one-way valve, the air after the air filter and the gas in the intake manifold will not be extracted by the large negative pressure in the first flow path 32.

[0063] When the engine water temperature rises (for example, when T>-10℃), the electrically controlled valve connected between the hydrogen rail and the crankcase 1 ventilation pipe can be controlled to disconnect regardless of the engine load. When the load is small, it is extracted to the intake manifold d through the manifold negative pressure and then enters the combustion chamber to be burned (and in order to avoid excessive negative pressure in the crankcase, fresh air is also added to the crankcase 1 through the air supply passage 54); when the load is large, it is extracted to the intake pipe after the air filter through the negative pressure after the air filter, and finally enters the combustion chamber to be burned. Due to the high oil temperature, water temperature and engine body temperature, water vapor is not easy to condense into liquid water, so disconnecting the second flow path 41 can meet the use requirements.

[0064] In addition, when the nozzle 35 is provided to spray the gas in the first flow path 32 into the combustion chamber, even if the engine is not in a low temperature environment, the second flow path 41 can be intermittently controlled to be connected according to a time interval (for example, time t=30 minutes). By extracting the engine oil vapor into the hydrogen spray nozzle, the plunger structure in the hydrogen spray nozzle is lubricated, thereby improving the reliability of the hydrogen spray nozzle.

[0065] Furthermore, the passage structure 5 further includes a pressure relief pipeline 55, the two ends of which are respectively connected to the air filter rear pipeline 511 and the intercooler rear pipeline 513, and a pressure relief valve 6 is provided on the pressure relief pipeline 55. When the vehicle decelerates, the throttle valve e is closed, and the gas pressurized by the supercharger b needs to be released to the air filter rear intake pipe through the pressure relief pipeline 55, otherwise it will cause excessive boost pressure and damage the engine supercharger b and the throttle valve e.

[0066] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention and the drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A hydrogen engine crankcase ventilation system, characterized in that: The hydrogen engine crankcase ventilation system comprises a crankcase, a combustion chamber and an oil-gas separator, and the hydrogen engine crankcase ventilation system further comprises: A hydrogen delivery device, comprising a hydrogen tank and a first flow path connected to the hydrogen tank, wherein the first flow path is connected to the combustion chamber; and The ventilation structure has a second flow path, and the second flow path is connected to the first flow path and the oil-gas separator, so that the mixed gas output by the oil-gas separator can be transported to the combustion chamber for combustion together with the hydrogen.

2. The hydrogen engine crankcase ventilation system according to claim 1, characterized in that: In the first flow path, a portion connected to the second flow path forms a connection, and a cross-sectional area of ​​the connection is smaller than a cross-sectional area of ​​the remaining portion of the first flow path.

3. The hydrogen engine crankcase ventilation system according to claim 2, characterized in that: The first flow path further includes a first hydrogen transmission flow path and a second hydrogen transmission flow path, the first hydrogen transmission flow path and the second hydrogen transmission flow path are both connected to the connection and are disposed on both sides of the connection, wherein: The first hydrogen transmission flow path comprises a first cavity section and a second cavity section which are connected to each other, the first cavity section is connected to the hydrogen tank, the second cavity section is connected to the connection, and the diameter of the second cavity section gradually decreases along the direction from the hydrogen tank to the connection; The second hydrogen supply flow path is connected to the combustion chamber, and the second hydrogen supply flow path includes a third cavity segment and a fourth cavity segment that are connected to each other. The third cavity segment is connected to the connection point, and the fourth cavity segment is connected to the combustion chamber. The diameter of the third cavity segment gradually decreases along the direction from the combustion chamber to the connection point.

4. The hydrogen engine crankcase ventilation system according to claim 3, characterized in that: The diameter of the first cavity segment is D1, the diameter of the connection is D2, and the diameter of the fourth cavity segment is D3, then: D1:D2 is (3-4):1; and / or, D3:D2 is (3~4):

1.

5. The hydrogen engine crankcase ventilation system according to claim 3, characterized in that: The first cavity section is provided with a pressure reducing valve.

6. The hydrogen engine crankcase ventilation system according to claim 3, characterized in that: The hydrogen delivery device also includes: A connecting member, the connecting member having a receiving cavity; and a nozzle, disposed outside the connecting member and connected to the accommodating chamber, the nozzle being connected to the combustion chamber to spray the gas in the accommodating chamber into the combustion chamber; Wherein, the fourth cavity section includes the accommodating cavity and the nozzle.

7. The hydrogen engine crankcase ventilation system according to claim 6, characterized in that: The nozzle is provided in plurality.

8. The hydrogen engine crankcase ventilation system according to claim 1, characterized in that: The second flow path is provided with a control valve.

9. The hydrogen engine crankcase ventilation system according to claim 1, characterized in that: The hydrogen engine crankcase ventilation system further includes an air filter device, a supercharger, an intercooler, an intake manifold connected to the engine intake pipeline, and a passage structure, wherein the passage structure includes: An intake passage, the two ends of which are connected to the air filter device and the intake manifold respectively, including a rear pipeline of the air filter, a rear pipeline of the supercharger and a rear pipeline of the intercooler connected in sequence, and a throttle valve is arranged on the rear pipeline of the intercooler; A first tortuous passage, the first tortuous passage is a gas passage under a light load condition, two ends of the first tortuous passage are respectively connected to the oil-gas separator and the intake manifold, and a first one-way valve is provided on the first tortuous passage; A second tortuous passage, the second tortuous passage is parallel to the first tortuous passage and is a gas passage under heavy load conditions, the two ends of the second tortuous passage are respectively connected to the oil-gas separator and the pipeline after the air filter, and a second one-way valve is provided on the second tortuous passage; and An air supply passage, two ends of which are respectively connected to the air filter post-pipeline and the crankcase, and a third one-way valve is provided on the air supply passage.

10. The hydrogen engine crankcase ventilation system according to claim 9, characterized in that: The passage structure further includes a pressure relief pipeline, two ends of which are respectively connected to the air filter rear pipeline and the intercooler rear pipeline, and a pressure relief valve is provided on the pressure relief pipeline.

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