Double tumble inlet cylinder head and hydrogen engine

Abstract

The present invention relates to the field of engine technology, specifically disclosing a dual-tumble intake cylinder head and a hydrogen engine. The dual-tumble intake cylinder head comprises a cylinder head body and two hydrogen intake pipes. The cylinder head body is provided with at least one set of intake and exhaust paths corresponding one-to-one with at least one piston cylinder on the engine body. The intake and exhaust paths include a first intake duct, a second intake duct, and an exhaust duct. The outlet of the first intake duct, the outlet of the second intake duct, and the intake of the exhaust duct all correspond to the corresponding piston cylinder on the engine body. The intake of the first intake duct and the intake of the second intake duct are independently arranged. The outlets of the two hydrogen intake pipes are inserted into the first and second intake ducts from their respective intake ports. Since the first and second intake ducts are independently arranged, if backfire occurs in one of the intake ducts, the backfire will not spread to all intake ducts, thereby improving the operating stability of the hydrogen engine.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to a dual-tumble intake cylinder head and a hydrogen engine. Background Art

[0002] As the global demand for environmental protection and energy conservation continues to deepen, it poses a huge challenge to traditional internal combustion engine commercial vehicle manufacturers. As a "zero" carbon fuel, the use of hydrogen energy has huge and long-term development potential. The current application methods of hydrogen energy are mainly hydrogen fuel cells and hydrogen internal combustion engines. Hydrogen fuel cells have the advantages of high efficiency and zero emissions, but they are technically difficult, costly, and highly dependent on the construction of supporting systems. The hydrogen internal combustion engine retains the main structure of the traditional internal combustion engine. The current internal combustion engine production line can be modified at a lower cost to achieve hydrogen internal combustion engine production. It can utilize industrial by-product hydrogen and is expected to achieve a thermal efficiency similar to that of fuel cells. It has considerable cost advantages and market potential. Therefore, the hydrogen internal combustion engine is an important technical direction to promote the upgrading and transformation of various application fields of traditional internal combustion engines and to help achieve carbon peak and carbon neutrality.

[0003] The key core technologies for developing hydrogen internal combustion engines are based on the fuel's properties. Hydrogen has excellent diffusivity, a low ignition point, and a fast combustion rate, but this presents technical challenges such as pre-ignition, detonation, and backfire. Traditional spark-ignition internal combustion engines typically use a single intake duct that bifurcates in the middle, directing air into the cylinder through two intake valves. When this structure is applied to hydrogen engines, if backfire occurs in one of the intake ducts, it can spread throughout the entire intake duct, resulting in poor operating stability for the hydrogen engine. Summary of the Invention

[0004] The purpose of the present invention is to provide a dual-tumble intake cylinder head and a hydrogen engine to solve the problem in the related art that the intake duct of a traditional spark-ignition internal combustion engine mostly adopts a single inlet, branches at the middle position and then introduces air into the cylinder through two intake valves. When this structure is used in a hydrogen engine, if one of the single intake ducts backfires, backfire will occur in the entire intake duct, resulting in poor operating stability of the hydrogen engine.

[0005] In one aspect, the present invention provides a dual tumble intake cylinder head, comprising a cylinder head body, wherein the cylinder head body is provided with at least one set of intake and exhaust paths for one-to-one correspondence with at least one piston cylinder on an engine block;

[0006] The intake and exhaust passages include a first intake passage, a second intake passage, and an exhaust passage, wherein the air outlet of the first intake passage, the air outlet of the second intake passage, and the air inlet of the exhaust passage are all used to correspond to the piston cylinder on the corresponding engine body, and the air inlet of the first intake passage and the air inlet of the second intake passage are independently arranged;

[0007] It also includes two hydrogen inlet pipes, and the gas outlets of the two hydrogen inlet pipes are respectively inserted into the first air inlet and the second air inlet from the air inlet of the first air inlet and the air inlet of the second air inlet.

[0008] As an optimal technical solution for the dual-tumble intake cylinder head, the angle between the plane of the cylinder head body used to fit with the engine body and the first intake duct is a, and the angle between the plane of the cylinder head body used to fit with the engine body and the second intake duct is b, 50°≤a≤65°, 50°≤b≤65°.

[0009] As a preferred technical solution for the dual tumble intake cylinder head, a first groove is provided at the bend of the first intake duct, and the first groove is close to the plane of the cylinder head body for fitting with the engine body;

[0010] A second groove is formed at the bend of the second air intake duct, and the second groove is close to the plane of the cylinder head body for fitting with the engine body.

[0011] As a preferred technical solution of the dual tumble intake cylinder head, it also includes a first valve and a second valve, wherein the first valve slides along the axis of the air outlet of the first intake passage and has two states of closing or opening the air outlet of the first intake passage, and the second valve slides along the axis of the air outlet of the second intake passage and has two states of closing or opening the air outlet of the second intake passage;

[0012] A first eccentric chamfer is provided on the hole wall of the air outlet of the first air inlet duct, and the distance between the center of the first eccentric chamfer and the axis of the first valve is D, and the center of the first eccentric chamfer is used to deflect toward the axis of the corresponding piston cylinder; a second eccentric chamfer is provided on the hole wall of the air outlet of the second air inlet duct, and the distance between the center of the second eccentric chamfer and the axis of the second valve is D, and the center of the second eccentric chamfer is used to deflect toward the axis of the corresponding piston cylinder.

[0013] As an optimal technical solution for a dual-tumble intake cylinder head, the angle between the side of the first eccentric chamfer close to the bend of the first intake duct and the plane of the cylinder head body used to fit with the engine body is β, and the angle between the side of the second eccentric chamfer close to the bend of the second intake duct and the plane of the cylinder head body used to fit with the engine body is β, and 45°≤β≤65°.

[0014] As an optimal technical solution for a dual-tumble intake cylinder head, the angle between the side of the first eccentric chamfer facing away from the bend of the first intake duct and the plane of the cylinder head body used to fit with the engine body is γ, and the angle between the side of the second eccentric chamfer facing away from the bend of the second intake duct and the plane of the cylinder head body used to fit with the engine body is γ; 30°≤γ≤55°, and γ<β.

[0015] As a preferred technical solution for the dual-tumble intake cylinder head, the outlets of the two hydrogen intake pipes are spaced apart from the outlet of the first intake duct and the outlet of the second intake duct respectively.

[0016] As a preferred technical solution for the dual-tumble intake cylinder head, the air intake of the exhaust passage includes a first air intake and a second air intake, and the first air intake and the second air intake are both opposite to the corresponding piston cylinder.

[0017] On the other hand, the present invention provides a hydrogen engine, comprising the engine body, a piston and a double-tumble intake cylinder head in any of the above schemes, wherein the cylinder head body is fixed to the engine body, the piston is located in the piston cylinder, and a third groove is provided on the surface where the piston abuts the cylinder head body.

[0018] As a preferred technical solution for the hydrogen engine, the ratio of the depth of the third groove to the diameter of the piston cylinder is in the range of 0.18-0.35.

[0019] The beneficial effects of the present invention are:

[0020] The present invention provides a dual-tumble intake cylinder head, a hydrogen engine, and a hydrogen engine. The dual-tumble intake cylinder head includes a cylinder head body and two hydrogen intake pipes. The cylinder head body is provided with at least one group of intake and exhaust paths for corresponding one-to-one with at least one piston cylinder on the engine body; the intake and exhaust paths include a first intake duct, a second intake duct, and an exhaust duct. The outlet of the first intake duct, the outlet of the second intake duct, and the intake of the exhaust duct are all used to correspond to the corresponding piston cylinders on the engine body, and the intake of the first intake duct and the intake of the second intake duct are independently arranged; the outlets of the two hydrogen intake pipes are respectively inserted into the first intake duct and the second intake duct from the intake of the first intake duct and the intake of the second intake duct. When a hydrogen engine equipped with this dual-tumble intake cylinder head is operating, air is injected into the first and second intake ducts, and hydrogen is injected into the first and second intake ducts respectively by two hydrogen intake pipes. The hydrogen and air in the first and second intake ducts mix and then enter the piston cylinder. Because the first and second intake ducts are independently configured, if backfire occurs in one of the first and second intake ducts, the backfire will not spread to all intake ducts, thereby improving the stability of the hydrogen engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The structure of the double tumble intake cylinder head in the embodiment of the present invention is schematically shown. Figure 1 ;

[0022] Figure 2 for Figure 1 Cross-sectional view at the middle BB;

[0023] Figure 3 Schematic diagram of the structure of the first eccentric chamfer in an embodiment of the present invention;

[0024] Figure 4 The structure of the double tumble intake cylinder head in the embodiment of the present invention is schematically shown. Figure 2 .

[0025] In the picture:

[0026] 1. Cylinder head body; 21. First intake duct; 211. First groove; 212. First eccentric chamfer; 22. Second intake duct; 222. Second eccentric chamfer; 23. Exhaust duct; 231. First intake port; 232. Second intake port; 3. Hydrogen intake pipe; 4. First valve; 5. Piston; 51. Third groove; 6. Piston cylinder; S. Tempering zone. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and the first feature being "above", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0029] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0030] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0031] like Figures 1 to 4 As shown, this embodiment provides a dual-tumble intake cylinder head, which includes a cylinder head body 1 and two hydrogen intake pipes 3. The cylinder head body 1 is provided with at least one group of intake and exhaust paths for corresponding one-to-one with at least one piston cylinder 6 on the engine body; the intake and exhaust paths include a first intake channel 21, a second intake channel 22 and an exhaust channel 23, and the outlet of the first intake channel 21, the outlet of the second intake channel 22 and the intake of the exhaust channel 23 are all used to correspond to the corresponding piston cylinder 6 on the engine body, and the intake of the first intake channel 21 and the intake of the second intake channel 22 are independently set; the outlets of the two hydrogen intake pipes 3 are inserted into the first intake channel 21 and the second intake channel 22 from the intake of the first intake channel 21 and the intake of the second intake channel 22 respectively. When a hydrogen engine equipped with this dual-tumble intake cylinder head is operating, air is injected into the first intake passage 21 and the second intake passage 22. The two hydrogen intake pipes 3 inject hydrogen into the first intake passage 21 and the second intake passage 22, respectively. At this time, the hydrogen and air in the first intake passage 21 and the second intake passage 22 mix and then enter the piston cylinder 6. Because the first intake passage 21 and the second intake passage 22 are independently provided, if backfire occurs in one of the first intake passage 21 and the second intake passage 22, the backfire will not spread to all intake passages, thereby improving the stability of the hydrogen engine.

[0032] Optionally, the angle between the plane of the cylinder head body 1 that fits the engine body and the first intake duct 21 is a, and the angle between the plane of the cylinder head body 1 that fits the engine body and the second intake duct 22 is b, 50°≤a≤65°, 50°≤b≤65°. In this embodiment, the purpose of the above-mentioned setting is to allow the gas entering the first intake duct 21 and the second intake duct 22 to enter the cylinder at a certain angle, which is conducive to the formation of tumble flow, and thus facilitates the mixing of air and hydrogen. The tumble flow duct has high turbulent kinetic energy; high turbulent kinetic energy can accelerate the flame propagation speed, improve thermal efficiency, and effectively suppress detonation. It has significant advantages in emissions, anti-detonation vibration, and improving the thermal efficiency of hydrogen engines, and can effectively suppress the risk of backfire.

[0033] Optionally, a first groove 211 is formed at the bend of the first intake duct 21, close to the plane of the cylinder head body 1 for contact with the engine block. A second groove is formed at the bend of the second intake duct 22, close to the plane of the cylinder head body 1 for contact with the engine block. In this embodiment, the first groove 211 serves to direct more gas from the first intake duct 21 to the outlet of the first intake duct 21, thereby increasing the tumble flow intensity. The second groove has the same structure as the first groove 211 and will not be further described here.

[0034] Optionally, the dual-tumble intake cylinder head also includes a first valve 4 and a second valve, the first valve 4 slides along the axis of the outlet of the first intake duct 21 and has two states of closing or opening the outlet of the first intake duct 21, and the second valve slides along the axis of the outlet of the second intake duct 22 and has two states of closing or opening the outlet of the second intake duct 22; a first eccentric chamfer 212 is provided on the hole wall of the outlet of the first intake duct 21, and the distance between the center of the first eccentric chamfer 212 and the axis of the first valve 4 is D, and the center of the first eccentric chamfer 212 is used to deflect toward the axis of the corresponding piston cylinder 6; a second eccentric chamfer 222 is provided on the hole wall of the outlet of the second intake duct 22, and the distance between the center of the second eccentric chamfer 222 and the axis of the second valve is D, and the center of the second eccentric chamfer 222 is used to deflect toward the axis of the corresponding piston cylinder 6.

[0035] Optionally, the angle β between the side of the first eccentric chamfer 212 closest to the bend of the first intake duct 21 and the plane of the cylinder head body 1 used to mate with the engine block is defined as β. The angle β between the side of the second eccentric chamfer 222 closest to the bend of the second intake duct 22 and the plane of the cylinder head body 1 used to mate with the engine block is defined as 45°≤β≤65°. In this embodiment, the angle β ensures sufficient intake volume for the piston cylinder 6 while also ensuring the overall strength of the dual-tumble intake cylinder head. Preferably, the value of β is 58°.

[0036] Optionally, the angle between the first eccentric chamfer 212, facing away from the first intake duct 21, and the plane of the cylinder head body 1 used to mate with the engine block is γ, and the angle between the second eccentric chamfer 222, facing away from the second intake duct 22, and the plane of the cylinder head body 1 used to mate with the engine block is γ; 30°≤γ≤55°, and γ<β. In this embodiment, an excessively large γ angle will not increase intake air volume and energy, while a too small γ angle will encroach on the wall thickness between the intake valve and the spark plug, increasing the risk of cracking. Preferably, the value of γ is 35°.

[0037] Optionally, the outlets of the two hydrogen inlet pipes 3 are spaced apart from the outlets of the first inlet duct 21 and the second inlet duct 22, respectively. In this embodiment, this arrangement can prevent damage to the hydrogen inlet pipe 3 within the first inlet duct 21 when flashback occurs in the first inlet duct 21, thereby keeping the hydrogen inlet pipe 3 within the first inlet duct 21 away from the flashback zone S. The spacing between the outlets of the hydrogen inlet pipe 3 and the outlet of the first inlet duct 21 is a preset value c, which is determined by simulating a flashback structure of the first inlet duct 21.

[0038] Optionally, the air inlet of the exhaust duct 23 includes a first air inlet 231 and a second air inlet 232, each of which is opposite to the corresponding piston cylinder 6. In this embodiment, a third valve and a fourth valve are also included. The third valve slides along the axis of the first air inlet 231 and has two states: closing or opening the first air inlet 231. The fourth valve slides along the axis of the second air inlet 232 and has two states: closing or opening the second air inlet 232. The combusted gas in the piston cylinder 6 enters the exhaust duct 23 through the first air inlet 231 and the second air inlet 232, and is then discharged from the exhaust port of the exhaust duct 23.

[0039] On the other hand, the present invention provides a hydrogen engine, comprising an engine body, a piston 5 and the dual-tumble intake cylinder head of the above-mentioned scheme, wherein the cylinder head body 1 is fixed to the engine body, the piston 5 is located in the piston cylinder 6, and the surface where the piston 5 abuts the cylinder head body 1 is concavely provided with a third groove 51. In this embodiment, a sealing ring is sandwiched between the engine body and the cylinder head body 1, and the sealing ring can ensure the sealing of the piston cylinder 6. The third groove 51 can enable the combustible gas in the cylinder to roll smoothly on the top of the piston 5 during the intake stroke and the compression stroke, thereby obtaining a suitable tumble flow intensity. Optionally, the ratio of the depth of the third groove 51 to the diameter of the piston cylinder 6 is in the range of 0.18-0.35.

[0040] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A double tumble intake cylinder head, comprising a cylinder head body (1), wherein the cylinder head body (1) is provided with at least one set of intake and exhaust paths for one-to-one correspondence with at least one piston cylinder (6) on an engine body; It is characterized by: The intake and exhaust paths include a first intake duct (21), a second intake duct (22) and an exhaust duct (23); the outlet of the first intake duct (21), the outlet of the second intake duct (22) and the intake of the exhaust duct (23) are all used to correspond to the piston cylinder (6) on the corresponding engine body; the intake of the first intake duct (21) and the intake of the second intake duct (22) are independently arranged; It also includes two hydrogen inlet pipes (3), the gas outlets of the two hydrogen inlet pipes (3) being inserted into the first inlet duct (21) and the second inlet duct (22) from the inlet of the first inlet duct (21) and the inlet of the second inlet duct (22), respectively; The included angle between the plane of the cylinder head body (1) used to fit the engine body and the first air intake duct (21) is a, and the included angle between the plane of the cylinder head body (1) used to fit the engine body and the second air intake duct (22) is b, 50°≤a≤65°, 50°≤b≤65°; The air outlet of the first air inlet duct (21) is closed or opened. The air outlet of the first air inlet duct (21) is closed or opened. The air outlet of the second air inlet duct (22) is closed or opened. A first eccentric chamfer (212) is provided on the hole wall of the air outlet of the first air inlet duct (21), the distance between the center of the first eccentric chamfer (212) and the axis of the first valve (4) is D, and the center of the first eccentric chamfer (212) is used to deflect toward the axis of the corresponding piston cylinder (6); a second eccentric chamfer (222) is provided on the hole wall of the air outlet of the second air inlet duct (22), the distance between the center of the second eccentric chamfer (222) and the axis of the second valve is D, and the center of the second eccentric chamfer (222) is used to deflect toward the axis of the corresponding piston cylinder (6); The angle between the first eccentric chamfer (212) near the side of the first air inlet (21) bent and the plane of the cylinder head body (1) used to fit with the engine body is β, and the angle between the second eccentric chamfer (222) near the side of the second air inlet (22) bent and the plane of the cylinder head body (1) used to fit with the engine body is β, and 45°≤β≤65°.

2. The dual tumble intake cylinder head according to claim 1, characterized in that: A first groove (211) is formed at the bend of the first air inlet duct (21), and the first groove (211) is close to the plane of the cylinder head body (1) for fitting with the engine body; A second groove is provided at the bend of the second air inlet duct (22), and the second groove is close to the plane of the cylinder head body (1) for fitting with the engine body.

3. The dual tumble intake cylinder head according to claim 1, characterized in that: The angle between the side of the first eccentric chamfer (212) that is away from the first intake duct (21) and the plane of the cylinder head body (1) used to fit with the engine body is γ, and the angle between the side of the second eccentric chamfer (222) that is away from the second intake duct (22) and the plane of the cylinder head body (1) used to fit with the engine body is γ; 30°≤γ≤55°, and γ<β.

4. The dual tumble intake cylinder head according to claim 1, characterized in that: The gas outlets of the two hydrogen gas inlet pipes (3) are spaced apart from the gas outlet of the first gas inlet duct (21) and the gas outlet of the second gas inlet duct (22).

5. The dual tumble intake cylinder head according to claim 1, characterized in that: The air inlet of the exhaust duct (23) comprises a first air inlet (231) and a second air inlet (232), and the first air inlet (231) and the second air inlet (232) are both opposite to the corresponding piston cylinder (6).

6. A hydrogen engine, characterized in that: The invention comprises the engine body, the piston (5) and the double tumble intake cylinder head according to any one of claims 1 to 5, wherein the cylinder head body (1) is fixed to the engine body, the piston (5) is located in the piston cylinder (6), and a third groove (51) is provided on the surface where the piston (5) contacts the cylinder head body (1).

7. The hydrogen engine according to claim 6, characterized in that: The ratio of the depth of the third groove (51) to the diameter of the piston cylinder (6) is in the range of 0.18-0.35.

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