Air cleaner device for hydrogen ammonia internal combustion engine

Abstract

The application relates to the technical field of air intake systems of hydrogen-ammonia internal combustion engines, in particular to an air filter device for a hydrogen-ammonia internal combustion engine, which comprises a front shell cover and a rear shell cover, the rear shell cover is detachably buckled and fixed with the front shell cover, a filter core is arranged between the front shell cover and the rear shell cover, a fixing cylinder extending away from the front shell cover is integrally formed in the middle of the rear shell cover, a back shock buffer is inserted and fixed on the inner side of the fixing cylinder, and the back shock buffer is used for dissipating high-frequency impact pressure waves transmitted from the side of the internal combustion engine to the air filter, so that the influence of the high-frequency impact pressure waves on the air filter is weakened. The back shock buffer is connected in series downstream of the filter core, the amplitude of the reverse impact pressure waves is attenuated through the shunt and vortex dissipation effect of the cooperation of the multiple U-shaped annular air ducts and the flow guide cone on the inner side of the back shock buffer, the slight shaking of the filter core caused by the alternating pressure impact can be effectively reduced, the dense structure of the filtering fiber layer can be maintained, and the particle interception precision can be stabilized.

Description

Technical Field

[0001] This invention relates to the field of intake system technology for hydrogen ammonia internal combustion engines, specifically to an air filter device for hydrogen ammonia internal combustion engines. Background Technology

[0002] The intake pressure fluctuation of a conventional internal combustion engine mainly comes from the reciprocating intake motion of the piston and the throttle valve's throttling effect. The pressure waveform is regular and controllable. Therefore, traditional air filters only need to be designed according to the steady-state intake resistance and the rated total intake flow rate to meet the long-term stable operation requirements of the engine.

[0003] The fuels used in hydrogen-ammonia internal combustion engines differ fundamentally from those in traditional gasoline and diesel internal combustion engines in terms of physical and chemical properties, which in turn fundamentally changes the working environment of the intake system.

[0004] To compensate for the technical shortcomings of pure ammonia fuel, such as slow flame propagation speed and poor combustion stability, existing hydrogen-ammonia internal combustion engines mostly adopt a composite fuel combustion scheme of ammonia mixed with hydrogen. By adding a small amount of hydrogen as a combustion activator, the combustion performance of ammonia fuel is improved. Since the laminar flame propagation speed of hydrogen is 7 to 8 times that of gasoline, the hydrogen-blended combustion method will significantly increase the pressure rise rate after ignition in the internal combustion engine cylinder. The high-frequency pressure oscillation intensity generated during the combustion process is much higher than that of traditional internal combustion engines. However, this type of high-intensity pressure oscillation cannot be completely confined to the inside of the cylinder, and it occurs at the intake and exhaust ports. When a slight backfire occurs due to the exhaust valve overlapping or high load conditions, the intense pressure oscillations inside the cylinder will be rapidly transmitted upstream along the intake manifold, causing severe and high-frequency pressure pulsations inside the intake manifold. For the air filter installed at the front end of the intake manifold, when this high-frequency impact pressure wave from the internal combustion engine side directly impacts the filter element inside the air filter, it will cause the filter element to vibrate slightly under continuous impact. This vibration will gradually damage the dense structure of the filter fiber layer, reducing the filter element's accuracy in intercepting particulate matter and the stability of filtration.

[0005] Therefore, the traditional air filter structure and performance system cannot adapt to the high-intensity, high-frequency dynamic pressure pulsation intake conditions of hydrogen-ammonia internal combustion engines, and cannot meet the reliable operation requirements of hydrogen-ammonia composite fuel internal combustion engines.

[0006] Therefore, the present invention proposes an air filter device for a hydrogen ammonia internal combustion engine. Summary of the Invention

[0007] The purpose of this invention is to provide an air filter device for a hydrogen-ammonia internal combustion engine, in order to solve the problems mentioned in the background art, that traditional air filters developed based on the characteristics of gasoline and diesel internal combustion engines cannot adapt to the extreme dynamic intake conditions of hydrogen-ammonia internal combustion engines, and have poor adaptability, insufficient reliability, and difficulty in meeting the long-term stable operation of hydrogen-ammonia composite fuel internal combustion engines.

[0008] To achieve the above objectives, the present invention provides the following technical solution: An air filter device for a hydrogen-ammonia internal combustion engine includes a front cover and a rear cover. The rear cover is detachably fastened to the front cover, and a filter element is installed between the front cover and the rear cover. A fixed cylinder extending away from the front cover is integrally formed in the middle of the rear cover. An anti-impact buffer is inserted and fixed to the inner side of the fixed cylinder to dissipate the high-frequency impact pressure wave transmitted from the internal combustion engine side toward the air filter, thereby weakening the impact of the high-frequency impact pressure wave on the air filter. The anti-impact buffer includes an annular shell. A first guide ring is integrally formed on the inner side of one end of the annular shell near the filter element. An annular mounting seat is integrally formed on the other end of the annular shell. At least two annular second air ducts are separated on the inner side of the annular shell by a second guide ring integrally formed in the middle. Each second air duct has a U-shaped cross-section structure formed by a third guide ring provided on the inner side. The air inlet and outlet of each second air duct are inclined at an angle of 30-45 degrees towards the mounting seat. The inner edge of each third guide ring extends towards the center of the annular shell and towards the mounting seat, forming a first air duct in the axial direction at the center of the annular shell. A guide cone is provided at the center of the first air duct.

[0009] Furthermore, the inner diameter of the mounting base is larger than the inner diameter of the second guide ring, while the inner diameters of the first and second guide rings are the same.

[0010] Furthermore, each of the third guide rings on the inner side of the second air duct has a number of support ribs integrally formed at intervals around the second air duct at the bottom, and each support rib is fixedly connected to the inner wall of the second air duct.

[0011] Furthermore, the portion of the inner edge of the third guide ring extending into the second air duct is designed with an arc-shaped bend towards the mounting base.

[0012] Furthermore, the air guide cone is coaxial with the first air duct, and the tip of the air guide cone is set towards the mounting base. At least one annular guide groove is opened on the outside of the air guide cone. Except for the third guide ring near the mounting base, the extension direction of the inner edge of each of the other third guide rings corresponds to a guide groove.

[0013] Furthermore, a plurality of supports are integrally formed between the outer side of the air guide cone and the first air guide ring, arranged at intervals around the circumference of the air guide cone.

[0014] Furthermore, the outer side of the annular shell is integrally formed with several reinforcing ribs arranged along the axial direction of the annular shell.

[0015] Furthermore, a flange ring is integrally formed on the inner edge of the end of the fixed cylinder away from the front cover. Several positioning blocks are integrally formed around the circumference of the flange ring at the connection between the inner side of the fixed cylinder and the flange ring. There are positioning slots between adjacent positioning blocks. The number of positioning slots is the same as the number of reinforcing ribs, and multiple reinforcing ribs are respectively engaged in the corresponding positioning slots.

[0016] Furthermore, an air outlet pipe is provided on the inner side of the fixed cylinder. The front end of the air outlet pipe extends out of the fixed cylinder from the inner side of the flange ring, and the tail end of the air outlet pipe is snapped between the mounting base and the flange ring. Both the tail end of the air outlet pipe and the mounting base are fixed to the flange ring by bolts.

[0017] Furthermore, the inner edge of the rear cover on the side that connects to the front cover has multiple spaced support platforms integrally formed around the circumference of the rear cover, and a support frame is also snapped into the inner side of the rear cover on the side that connects to the front cover, and the bottom of the filter element abuts against the support frame.

[0018] Furthermore, the support frame includes a fixing frame, the outer wall of which is in close contact with the inner wall of the rear cover, and the bottom edge of the fixing frame abuts against the support platform. A stainless steel mesh is fixed in the middle of the fixing frame, and multiple support columns with end faces abutting against the rear cover are distributed at the bottom of the fixing frame.

[0019] Furthermore, after the front cover and the rear cover are fastened together, the inner edge of the front cover on the side where it meets the rear cover abuts against the frame of the filter element edge; a U-shaped sealing ring is snapped into the side of the frame of the filter element edge that abuts against the front cover, and a sealing ring that snaps into the U-shaped sealing ring is integrally formed on the inner edge of the front cover on the side where it meets the rear cover.

[0020] Furthermore, the outer side of the rear cover is integrally formed with multiple buckles and second fixing ears, and the edge of the front cover is integrally formed with a fixing buckle and a first fixing ear that cooperate with the buckles and second fixing ears provided on the rear cover. The buckles and the fixing buckle are fastened to each other, and the first fixing ear and the second fixing ear abut against each other and are fixed together by screws.

[0021] Furthermore, an air inlet pipe is integrally formed in the middle of the side of the front cover away from the rear cover. An air distribution mesh is installed on the inner side of the front cover that is connected to the rear cover through multiple integrally formed mounting platforms and screws. The side of the air distribution mesh away from the filter element and the inner side of the front cover form an air distribution cavity.

[0022] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes a reverse impact buffer connected in series downstream of the filter element. By employing the diversion and eddy current dissipation effects of the multi-layered U-shaped annular air ducts and guide cones on the inner side of the reverse impact buffer, the amplitude of the reverse impact pressure wave is attenuated. This effectively reduces the slight vibration of the filter element caused by alternating pressure impact, helps maintain the dense structure of the filter fiber layer, and stabilizes the particulate matter interception accuracy. Moreover, the reverse impact buffer adopts a composite flow channel structure design with a central straight-through main air duct and an outer buffer air duct. This design results in lower resistance during forward air intake, making it less likely to affect the intake flow and power output of the internal combustion engine under rated operating conditions. Furthermore, the bidirectional clamping and limiting of the bottom support frame and the front edge frame of the filter element further reduces the vibration amplitude of the filter element and improves the stability of air filtration. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the disassembled structure of an air filter device for a hydrogen-ammonia internal combustion engine according to the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the disassembled structure of an air filter device for a hydrogen-ammonia internal combustion engine according to the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the rear cover structure in an air filter device for a hydrogen ammonia internal combustion engine according to the present invention. Figure 4 This is a half-sectional view of the anti-impact buffer in an air filter device for a hydrogen-ammonia internal combustion engine according to the present invention. Figure 5 This is a schematic diagram of the front cover structure of an air filter device for a hydrogen ammonia internal combustion engine according to the present invention; Figure 6 This is a half-sectional view of the support frame in an air filter device for a hydrogen ammonia internal combustion engine according to the present invention. Figure 7 This is a schematic diagram of the air distribution mesh in an air filter device for a hydrogen-ammonia internal combustion engine according to the present invention; Figure 8 This is a schematic cross-sectional view of an air filter device for a hydrogen ammonia internal combustion engine according to the present invention. Figure 9 This is a three-dimensional cross-sectional view of an air filter device for a hydrogen ammonia internal combustion engine according to the present invention; Figure 10 This is a schematic diagram of the overall structure of an air filter device for a hydrogen ammonia internal combustion engine according to the present invention; Figure 11 This is a schematic diagram of air flowing towards the internal combustion engine side through the anti-impact buffer. Figure 12 This is a schematic diagram of airflow as it flows from the internal combustion engine side toward the air filter and passes through the anti-impact buffer.

[0024] In the attached diagram, the components represented by each number are as follows: 1. Front cover; 101. Air inlet duct; 102. Mounting platform; 103. Sealing ring; 104. Fixing buckle; 105. First fixing ear; 2. Rear cover; 201. Fixing cylinder; 202. Flange ring; 203. Positioning block; 204. Positioning slot; 205. Support; 206. Buckle; 207. Second fixing ear; 3. Air distribution mesh; 4. Air outlet duct; 5. Anti-impact buffer; 501. Annular cover; 5 02. First guide ring; 503. Mounting base; 504. Second guide ring; 505. Second air duct; 506. Support rib; 507. Third guide ring; 508. First air duct; 509. Bracket; 510. Air guide cone; 511. Air guide groove; 512. Reinforcing rib; 6. Support frame; 601. Fixing frame; 602. Stainless steel mesh; 603. Support column; 7. Filter element; 8. U-shaped sealing ring; 9. Air distribution chamber. Detailed Implementation

[0025] 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.

[0026] This invention provides a technical solution: such as Figure 1 - Figure 10 The air filter device for a hydrogen-ammonia internal combustion engine shown includes a front cover 1 and a rear cover 2. The rear cover 2 is detachably fastened to the front cover 1, and a filter element 7 is installed between the front cover 1 and the rear cover 2. The front cover 1 and the rear cover 2 adopt a split and detachable fastening structure, which allows the air filter housing to be quickly disassembled during equipment maintenance, making it easy for operators to directly remove the internal filter element 7 for replacement, reducing the difficulty of daily maintenance of the air filter. Moreover, the inside of the housing after fastening forms a closed accommodating cavity, which can stably fix the filter element 7 and build a complete air circulation channel, ensuring that all external air intake passes through the filter element 7 before entering the internal combustion engine intake.

[0027] The backfire impact of a hydrogen-ammonia internal combustion engine is not a single constant high pressure, but a continuous pulsating wave formed by high-frequency pressure oscillations in the cylinder transmitted along the intake manifold. The pressure amplitude alternates periodically between normal intake negative / normal pressure and the peak value of backfire high pressure. For filter element 7, this is a periodic alternating load, which can cause fatigue vibration and structural loosening of the fiber layer in the long term. In order to reduce the impact of high-frequency impact pressure waves from the hydrogen-ammonia internal combustion engine side on filter element 7, a fixed cylinder 201 extending away from the front cover 1 is integrally formed in the middle of the rear cover 2. A flange ring 202 is integrally formed on the inner edge of the fixed cylinder 201 away from the front cover 1. An anti-impact buffer 5 is inserted and fixed inside the fixed cylinder 201 to dissipate the high-frequency impact pressure waves transmitted from the internal combustion engine side towards the air filter, thereby weakening the impact of high-frequency impact pressure waves on the air filter. Specifically, the fixed cylinder 201 extends axially behind the rear cover 2, forming an independent mounting cavity between the filter element 7 and the intake manifold of the internal combustion engine. The back impact buffer 5 is arranged in series in the airflow passage downstream of the filter element 7. When the high-frequency impact pressure wave generated by in-cylinder backfire is transmitted in the reverse direction along the intake passage, the impact airflow will first pass through the back impact buffer 5. Relying on the special flow channel structure inside the buffer, the kinetic energy carried by the high-frequency impact pressure wave is dissipated step by step, which can effectively reduce the impact pressure value transmitted to the surface of the filter element 7. This alleviates the slight vibration of the filter element 7 caused by the high-frequency pulsating pressure impact, and avoids structural damage such as loosening and breakage of the filter fiber layer of the filter element 7 under long-term periodic vibration. It stabilizes the interception accuracy of the filter element 7 for particulate matter, so that the air filter can adapt to the special intake conditions of high intensity and high frequency dynamic pressure pulsation of the hydrogen ammonia internal combustion engine.

[0028] The anti-impact buffer 5 includes an annular housing 501. A first guide ring 502 is integrally formed on the inner side of one end of the annular housing 501 near the filter element 7. An annular mounting seat 503 is integrally formed on the other end of the annular housing 501. At least two annular second air ducts 505 are separated on the inner side of the annular housing 501 by a second guide ring 504 integrally formed in the middle. Figure 4As shown, each second air duct 505 has a U-shaped cross-section structure formed by a third guide ring 507 set on its inner side. The air inlet and outlet of each second air duct 505 are inclined at an angle of 30-45 degrees towards the mounting base 503. The inner edge of each third guide ring 507 extends towards the center of the annular housing 501 and towards the mounting base 503, forming a first air duct 508 axially at the center of the annular housing 501. A guide cone 510 is provided at the center of the first air duct 508. In this design, the annular housing 501 acts as... The overall bearing shell of the anti-impact buffer 5 provides a forming and supporting foundation for the internal guide rings and air duct structures. The annular shape can be adapted to the circular intake pipe connected to the internal combustion engine side, and can also be directly embedded inside the fixed cylinder 201. The annular mounting seat 503 is integrally formed on the end of the annular shell 501 facing the internal combustion engine, providing a flat fitting reference surface for the assembly of the anti-impact buffer 5 and the flange ring 202 at the end of the fixed cylinder 201. This ensures that the buffer axis is completely coaxial with the intake channel of the whole machine after assembly, preventing airflow eccentricity from generating additional turbulence and intake resistance.

[0029] The second guide ring 504 radially divides the interior of the annular casing 501 into at least two stacked annular second air ducts 505, which can divert the concentrated high-pressure impact airflow from the internal combustion engine side into multiple independent sub-airflows. This diversion directly reduces the impact pressure of a single airflow, achieving the first stage of attenuation of the high-frequency impact pressure wave. The third guide ring 507, in conjunction with the second air ducts 505, forms a U-shaped cross-section flow channel. After entering the U-shaped flow channel, the reverse impact airflow needs to undergo a nearly 180-degree flow reversal. During this reversal, the airflow forms a strong local vortex, which, through the viscous friction within the air mass and the contact friction between the airflow and the duct wall, reduces the impact pressure. The kinetic energy carried by the high-frequency impact pressure wave is converted into heat energy and dissipated, achieving the second stage of impact energy attenuation. Moreover, when the airflow entering the second air duct 505 rushes out from the outlet end of the second air duct 505, the airflow direction is towards the internal combustion engine side. Therefore, this airflow will generate a counter-current with the remaining impact airflow that has not entered the interior of the second air duct 505 and flows along the surface of the guide cone 510 towards the filter element 7, thereby greatly dissipating the impact kinetic energy of this part of the impact airflow. This further reduces the impact of the pulsating impact generated by the high frequency and high pressure on the filter element 7, thereby avoiding damage to the filter element 7 and ensuring that the filter element 7 maintains an effective air filtration effect within the normal service life.

[0030] In addition, such as Figure 11 - Figure 12 As shown, although the anti-impact buffer 5 proposed in this application shares commonalities with the traditional Tesla valve in terms of core principles, there are significant differences in structural design and core effects, as detailed below: The anti-impact buffer 5 adopts a composite flow channel design with a central DC path and an outer multi-layer annular buffer path. Under normal forward air intake conditions, most of the intake air flow flows directly along the central first air duct 508, with only a small portion of the airflow entering the outer second air duct 505. The overall forward flow resistance is much lower than that of traditional full-channel reversible Tesla valves, which can fully guarantee the large flow rate intake requirements of hydrogen-ammonia internal combustion engines under rated conditions. It will not cause problems such as insufficient intake or reduced power output due to the addition of a buffer structure. In contrast, traditional single-channel Tesla valves are mostly flat structures. Under limited size constraints, their flow channels are narrow. To allow a large amount of air to flow smoothly, it is often necessary to simultaneously increase the valve body size. Moreover, although traditional Tesla valves have a large resistance difference when the medium flows in the forward and reverse directions, their forward flow capacity is limited, making it difficult to directly adapt to the intake of large-diameter internal combustion engines. In addition to meeting the flow requirements of the pipeline, the multi-layered second air duct 505 design surrounding the first air duct 508 is equivalent to multiple Tesla-like buffer units working in parallel along the circumference. It can simultaneously withstand large-section reverse impact airflow, adapting to the circular cross-sectional characteristics of the internal combustion engine intake pipe. Multi-stage buffering can be achieved within a limited axial installation space, with a space utilization rate higher than that of a single-channel Tesla valve. Furthermore, in each layer of the U-shaped second air duct 505, both the air inlet and outlet are inclined at 30 to 45 degrees toward the mounting base 503. At this angle, after the reverse impact airflow enters the air duct, its airflow reversal path is longer, the vortex formation is more complete, and the energy dissipation efficiency is higher. At the same time, the inclined outlet can guide the peripheral airflow to smoothly merge into the main airflow during forward air intake, avoiding airflow separation and local resistance caused by right-angle outlets, further reducing forward air intake losses.

[0031] Finally, the inner edges of multiple third guide rings 507 converge towards the center, together enclosing the first air duct 508 that runs through the axis, forming a dual-channel parallel structure with forward air delivery in the central channel and reverse impact buffering in the outer multi-channel, taking into account the dual needs of forward high-flow air intake and reverse high-pressure impact buffering.

[0032] Moreover, the air guide cone 510 set in the center of the first air duct 508 can evenly disperse the high-pressure airflow concentrated at the axis to the surrounding area during reverse impact, guide the impact airflow into the second air duct 505 of each layer to complete energy attenuation, and avoid the central airflow directly passing through the anti-impact buffer 5 and causing a strong impact on the filter element 7, which can effectively improve the overall wave elimination efficiency of the anti-impact buffer 5.

[0033] In this embodiment, the inner diameter of the mounting base 503 is larger than the inner diameter of the second guide ring 504, and the inner diameters of the first guide ring 502 and the second guide ring 504 are the same. The inner diameter of the mounting base 503 is set to be larger than the inner diameter of the second guide ring 504, so that the opening area of ​​the back impact buffer 5 facing the internal combustion engine side can completely cover the flow section of the back impact airflow on the internal combustion engine side, so that the high-pressure pulse airflow generated by backfire can effectively enter the internal air duct of the buffer.

[0034] In this embodiment, the bottom of the third guide ring 507 on the inner side of each second air duct 505 is integrally formed with a plurality of support ribs 506 arranged circumferentially around the second air duct 505, and each support rib 506 is fixedly connected to the inner wall of the second air duct 505. The support ribs 506 arranged at intervals around the second air duct 505 can rigidly connect the third guide ring 507 to the inner wall of the second air duct 505 into a whole, which can effectively improve the structural stability and vibration resistance of each guide ring. When the high-frequency high-pressure impact airflow continuously and repeatedly scours the third guide ring 507, the support ribs 506 can effectively share the alternating load generated by the airflow impact, avoiding the problem of deformation and fatigue fracture of the third guide ring 507 under long-term alternating stress. At the same time, the support ribs 506 are distributed at intervals, which will not completely block the flow section of the second air duct 505, but will only slightly disturb the local airflow direction, help increase the degree of airflow turbulence in the second air duct 505, and further improve the dissipation effect of high-frequency impact pressure wave energy.

[0035] In this embodiment, the portion of the inner edge of the third guide ring 507 extending out of the second air duct 505 is designed with an arc-shaped bend towards the mounting base 503. In this design, the arc-shaped bend of the inner edge of the third guide ring 507 can smoothly guide the airflow to complete the flow direction change. Compared with the right-angle folded edge structure, the arc-shaped transition surface can effectively prevent the generation of airflow dead zones. At the same time, when the air filter is in the forward direction, it can reduce the airflow separation phenomenon and reduce the local air intake resistance. When the reverse impact airflow flows through the arc-shaped guide surface, its airflow turning process is smoother, which can avoid the stress concentration problem of the right-angle edge, thereby improving the service life of the third guide ring 507 under high-frequency impact load.

[0036] In this embodiment, the air guide cone 510 is coaxial with the first air duct 508, and the tip of the air guide cone 510 is positioned towards the mounting base 503. At least one annular guide groove 511 is provided on the outer side of the air guide cone 510. Except for the third guide ring 507 near the mounting base 503, the extension direction of the inner edge of each of the remaining third guide rings 507 corresponds to a guide groove 511. When the high-frequency impact pressure wave transmitted in the reverse direction from the internal combustion engine side passes through the reverse impact buffer 5, the reverse impact airflow located in the outer region of the intake duct is generated from the inner edge of the mounting base 503 and the third guide groove 511 near the mounting base 503. The airflow enters the second air duct 505 near the mounting base 503 between the guide rings 507. The remaining impact airflow continues to flow towards the filter element 7 through the first air duct 508. The impact airflow entering the second air duct 505 is guided by the second air duct 505 and rushes out from the outlet of the second air duct 505. The airflow direction is towards the mounting base 503 side, forming a counter-impact with the impact airflow advancing towards the filter element 7 along the first air duct 508. A counter-impact vortex is formed in the outer area where the outlet of the second air duct 505 connects with the first air duct 508, dissipating the kinetic energy of the impact airflow on the outer layer of the first air duct 508.

[0037] In addition, in this embodiment, the tip of the guide cone 510 faces the mounting base 503. After the impact airflow generated by the backfire on the internal combustion engine side is diverted by the second air duct 505 near the mounting base 503, the remaining impact airflow advancing towards the filter element 7 along the first air duct 508 will first strike the tip of the guide cone 510. The conical slope of the guide cone 510 can evenly disperse the high-pressure airflow concentrated at the axial center to the surrounding area. It should be further explained that the reverse impact airflow has diffusion properties. After entering the first air duct 508 through the inner edge of the third guide ring 507, it will naturally expand and diffuse radially. The airflow rushing out from the outlet of the second air duct 505 near the mounting base 503 will first contact the impact airflow in the outer region of the first air duct 508 and form a counter-current vortex. Part of the impact airflow in the layer region will pass through the edge of the counter-current vortex and continue to flow towards the filter element 7 along the surface of the guide cone 510. At this time, since the annular guide groove 511 on the outside of the guide cone 510 corresponds to the extension direction of the inner edge of the corresponding third guide ring 507, the impact airflow flowing along the cone surface of the guide cone 510 will be guided by the groove wall to undergo radial deflection outward when passing through the guide groove 511, and will enter the second air duct 505 of the corresponding layer, realizing the orderly buffering of airflow layering. Moreover, the guide cone 510 and the first air duct 508 are arranged coaxially, which can ensure that the reverse pulsating impact airflow is completely symmetrical during the diversion process, so that the overall force of the buffer is uniform and there will be no unilateral load vibration, thereby effectively improving the stability of the operation of the anti-impact buffer 5.

[0038] In this embodiment, a plurality of supports 509 are integrally formed between the outer side of the air guide cone 510 and the first guide ring 502, arranged at intervals around the circumference of the air guide cone 510. The multiple supports 509 evenly distributed along the circumference can rigidly fix the air guide cone 510 at the center position of the first guide ring 502, forming a stable suspended support structure that can resist the alternating impact force brought by repeated impacts of high-frequency pressure waves, and prevent the air guide cone 510 from becoming eccentric, deviating, or falling off during long-term operation. Moreover, the supports 509 are arranged at intervals, with sufficient flow gaps reserved between adjacent supports 509, so as not to block the airflow channel of the central first air duct 508, effectively balancing structural support strength and air intake flow capacity.

[0039] In this embodiment, a plurality of reinforcing ribs 512 are integrally formed around the outer circumference of the annular housing 501 and arranged axially along the annular housing 501. A plurality of positioning blocks 203 are integrally formed around the circumference of the flange ring 202 at the connection point between the inner side of the fixing cylinder 201 and the flange ring 202. Positioning slots 204 are located between adjacent positioning blocks 203. The number of positioning slots 204 is the same as the number of reinforcing ribs 512, and the multiple reinforcing ribs 512 are respectively engaged in the corresponding positioning slots 204. In this design, the reinforcing ribs 512 arranged axially... It can effectively improve the bending and impact resistance of the cylinder wall of the annular shell 501. When the high-pressure reverse impact airflow generates radial expansion pressure inside the shell, the reinforcing rib 512 can effectively disperse the stress of the cylinder wall and prevent the annular shell 501 from undergoing plastic deformation. At the same time, the reinforcing rib 512 can also serve as a positioning and insertion structure, which can cooperate with the positioning slot 204 inside the fixed cylinder 201 to realize the circumferential limit of the anti-impact buffer 5. During assembly, it can be directly pushed in along the slot to complete the alignment without the need for additional positioning tooling, which can effectively improve the assembly efficiency.

[0040] In this embodiment, an air outlet pipe 4 is also provided inside the fixed cylinder 201. The front end of the air outlet pipe 4 extends out of the fixed cylinder 201 from the inside of the flange ring 202. The tail end of the air outlet pipe 4 is snapped between the mounting base 503 and the flange ring 202. The tail end of the air outlet pipe 4 and the mounting base 503 are both fixed to the flange ring 202 by bolts. The air outlet pipe 4 is arranged on the outermost side of the fixed cylinder 201 and is used to connect to the intake manifold of the hydrogen-ammonia internal combustion engine. The forward-flowing and filtered clean air passes through the anti-impact buffer 5 and is stably delivered from the air outlet pipe 4 to the intake manifold of the internal combustion engine. The tail end of the air outlet pipe 4 is clamped between the mounting base 503 of the anti-impact buffer 5 and the flange ring 202. Only one set of bolts is needed to complete the locking assembly of the two parts, the air outlet pipe 4 and the anti-impact buffer 5, which simplifies the assembly process between the anti-impact buffer 5, the air outlet pipe 4 and the rear cover 2.

[0041] In this embodiment, a plurality of spaced-apart support platforms 205 are integrally formed around the inner edge of the rear cover 2 on the side where it connects to the front cover 1. A support frame 6 is also snapped onto the inner side of the rear cover 2 on the side where it connects to the front cover 1. The bottom of the filter element 7 abuts against the support frame 6. In this design, the support platforms 205 arranged around the inner side of the rear cover 2 provide a bottom support base for the support frame 6. Moreover, the spaced-apart arrangement of the support platforms 205 can both distribute the weight load of the support frame 6 and the filter element 7 and enhance the strength of the rear cover 2. The support frame 6 is snapped into the inside of the rear cover 2, and the bottom of the filter element 7 is completely fitted against the support frame 6, providing a bottom support base for the installation of the filter element 7. The support frame 6 includes a fixing frame 601, the outer wall of the fixing frame 601 is in close contact with the inner wall of the rear cover 2, and the bottom edge of the fixing frame 601 abuts against the support platform 205. A stainless steel mesh 602 is fixed in the middle of the fixing frame 601, and multiple support columns 603 with end faces abutting against the rear cover 2 are distributed at the bottom of the fixing frame 601. In the design of the entire support frame 6, the outer side of the fixing frame 601... The sidewalls are tightly fitted to the inner wall of the rear cover 2, and the bottom is supported by the support platform 205, enabling bidirectional lateral and vertical positioning of the support frame 6. This prevents displacement and movement under the vibration conditions of the internal combustion engine. Furthermore, the stainless steel mesh 602 in the middle of the fixing frame 601 possesses high strength and corrosion resistance. The perforated mesh structure evenly supports the entire filter surface of the filter element 7, dispersing the impact pressure on the localized load of the filter element 7 and preventing localized dents and deformation. Simultaneously, the perforated structure of the stainless steel mesh 602 does not obstruct normal airflow. In addition to increasing air intake resistance, the multiple support columns 603 at the bottom of the mounting bracket 601, on the one hand, evenly transfer the load of the mounting bracket 601 and the filter element 7 to the housing of the rear cover 2, improving the overall impact resistance of the support bracket 6; on the other hand, through the cooperation of the support columns 603, an air flow space is formed between the side of the support bracket 6 away from the filter element 7 and the housing of the rear cover 2, so that the air filtered by the filter element 7 can smoothly enter the first air duct 508 in the center of the anti-impact buffer 5, thereby completing the forward air intake.

[0042] In this embodiment, after the front cover 1 and the rear cover 2 are fastened together, the inner edge of the front cover 1 on the side where it meets the rear cover 2 abuts against the frame of the filter element 7. A U-shaped sealing ring 8 is snapped into the side of the frame of the filter element 7 that abuts against the front cover 1. A sealing ring 103 that engages with the U-shaped sealing ring 8 is integrally formed on the inner edge of the front cover 1 on the side where it meets the rear cover 2. In this design, the inner edge of the front cover 1 presses against the frame of the filter element 7, and together with the bottom support frame 6, a bidirectional clamping and positioning structure is formed on both sides of the filter element 7. The filter element 7 is effectively restricted from axial displacement. The U-shaped sealing ring 8 is snapped between the frame of the filter element 7 and the front cover 1. When the front cover 1 and the rear cover 2 are fastened together, the sealing ring 103 is embedded in the groove of the U-shaped sealing ring 8 to form a seal. This effectively prevents unfiltered air from entering the air outlet pipe 4 through the gap between the frame and the housing of the filter element 7, ensuring that all the air entering the internal combustion engine is filtered by the filter element 7. In addition, it should be noted that the filter element 7 is embedded in the inner side of the support frame 6, which can realize the circumferential limitation of the filter element 7.

[0043] In this embodiment, the outer side of the rear cover 2 is integrally formed with multiple buckles 206 and second fixing ears 207. The edge of the front cover 1 is integrally formed with a fixing buckle 104 and a first fixing ear 105 that cooperate with the buckles 206 and second fixing ears 207 provided on the rear cover 2. The buckles 206 and the fixing buckles 104 are fastened together. The first fixing ears 105 and the second fixing ears 207 abut against each other and are fixed together by screws. The buckles 206 and the fixing buckles 104 can cooperate to realize The quick pre-fixing between the front cover 1 and the rear cover 2 eliminates the need for prolonged hand-holding alignment during assembly, allowing a single person to complete the initial assembly and improving assembly efficiency. Meanwhile, the first fixing ear 105 and the second fixing ear 207 are locked together by screws to form a mechanical lock, which can compensate for the defect of the buckle 206 being prone to loosening under long-term alternating vibration. Moreover, the double fixing structure can keep the fastening gap between the front cover 1 and the rear cover 2 in a continuously compressed and sealed state, which can effectively prevent air leakage from the air filter during long-term use.

[0044] In this embodiment, an air inlet pipe 101 is integrally formed in the middle of the side of the front cover 1 away from the rear cover 2. An air distribution mesh 3 is installed on the inner side of the front cover 1 connected to the rear cover 2 via multiple integrally formed mounting platforms 102 and screws. The side of the air distribution mesh 3 away from the filter element 7 forms an air distribution cavity 9 with the inner side of the front cover 1. In this design, the air inlet pipe 101 is integrally formed at the front end of the front cover 1, serving as the only inlet for outside air to enter the air filter. The air distribution mesh 3 is stably fixed to the inner side of the front cover 1 via the mounting platforms 102. The inner wall of the front cover 1 forms an independent air distribution cavity 9. After the outside air enters the air distribution cavity 9 through the air inlet pipe 101, it diffuses fully in the cavity and is then evenly distributed to the entire filter surface of the filter element 7 through the mesh of the air distribution net 3. This can effectively prevent the airflow from concentrating and impacting local areas of the filter element 7, thereby balancing the filtration load of each area of ​​the filter element 7 and extending the overall service life of the filter element 7. At the same time, the mesh structure of the air distribution net 3 can initially intercept large particles of impurities such as leaves and sand, preventing large particles of debris from directly impacting the filter element 7 body and causing damage to the filter fibers in the filter element 7.

[0045] In addition, it should be noted that, in order to adapt the air filter to the fuel chemistry of the hydrogen-ammonia internal combustion engine, and considering the special operating conditions of the hydrogen-ammonia internal combustion engine intake environment, which includes ammonia corrosion, hydrogen permeation, and high-frequency pressure pulsation, the material selection of each core component is designed to match corrosion resistance, structural strength, vibration reduction, and noise reduction. Among these options, the filter material of filter element 7 is PTFE-coated glass fiber filter paper; the anti-impact buffer 5 is made of nylon PA12 material or glass fiber reinforced PA12 material, and is integrally formed by laser sintering (SLS) 3D printing process to make its surface smooth and rounded; the front cover 1, the rear cover 2, and the air outlet pipe 4 are injection molded from glass fiber reinforced polypropylene (PP-GF30) or glass fiber reinforced polyphenylene sulfide (PPS-GF40).

[0046] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0047] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An air filter device for a hydrogen-ammonia internal combustion engine, comprising a front cover and a rear cover, wherein the rear cover and the front cover are detachably fastened together, and a filter element is installed between the front cover and the rear cover, characterized in that, The rear cover has an integrally formed fixed cylinder in the middle that extends away from the front cover, and an anti-impact buffer is inserted and fixed to the inner side of the fixed cylinder. The anti-impact buffer includes an annular shell. A first guide ring is integrally formed on the inner side of one end of the annular shell near the filter element. An annular mounting seat is integrally formed on the other end of the annular shell. At least two annular second air ducts are separated on the inner side of the annular shell by a second guide ring integrally formed in the middle. Each second air duct has a U-shaped cross-section structure formed by a third guide ring provided on the inner side. The air inlet and outlet of each second air duct are inclined at an angle of 30-45 degrees towards the mounting seat. The inner edge of each third guide ring extends towards the center of the annular shell and towards the mounting seat, forming a first air duct in the axial direction at the center of the annular shell. A guide cone is provided at the center of the first air duct.

2. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The inner diameter of the mounting base is larger than the inner diameter of the second guide ring, and the inner diameters of the first and second guide rings are the same.

3. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The bottom of the third guide ring on the inner side of each second air duct is integrally formed with several support ribs arranged at intervals around the circumference of the second air duct, and each support rib is fixedly connected to the inner wall of the second air duct.

4. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The portion of the inner edge of the third guide ring extending into the second air duct is designed with an arc-shaped bend towards the mounting base.

5. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The air guide cone is coaxial with the first air duct, and the tip of the air guide cone is set towards the mounting base. At least one annular guide groove is opened on the outside of the air guide cone. Except for the third guide ring near the mounting base, the extension direction of the inner edge of each of the other third guide rings corresponds to a guide groove. Several supports are integrally formed between the outer side of the air guide cone and the first air guide ring, arranged at intervals around the circumference of the air guide cone.

6. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The outer side of the annular shell is integrally formed with several reinforcing ribs arranged along the axial direction of the annular shell.

7. An air filter device for a hydrogen-ammonia internal combustion engine according to claim 6, characterized in that, A flange ring is integrally formed on the inner edge of the end of the fixed cylinder away from the front cover. Several positioning blocks are integrally formed around the circumference of the flange ring at the connection between the inner side of the fixed cylinder and the flange ring. There are positioning slots between adjacent positioning blocks. The number of positioning slots is the same as the number of reinforcing ribs, and multiple reinforcing ribs are respectively engaged in the corresponding positioning slots. The inner side of the fixed cylinder is also provided with an air outlet pipe. The front end of the air outlet pipe extends out of the fixed cylinder from the inner side of the flange ring, and the tail end of the air outlet pipe is snapped between the mounting base and the flange ring. Both the tail end of the air outlet pipe and the mounting base are fixed to the flange ring.

8. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The inner edge of the rear cover that connects to the front cover has multiple spaced support platforms integrally formed around the circumference of the rear cover. A support frame is also snapped into the inner side of the rear cover that connects to the front cover. The bottom of the filter element abuts against the support frame. The support frame includes a fixed frame, the outer wall of which is in close contact with the inner wall of the rear cover, and the bottom edge of the fixed frame abuts against the support platform. A stainless steel mesh is fixed in the middle of the fixed frame, and multiple support columns with end faces abutting against the rear cover are distributed at the bottom of the fixed frame.

9. The air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, After the front cover and the rear cover are fastened together, the inner edge of the front cover on the side where it meets the rear cover abuts against the frame of the filter element edge; a U-shaped sealing ring is snapped into the side of the filter element edge where it meets the front cover, and a sealing ring that snaps into the U-shaped sealing ring is integrally formed on the inner edge of the front cover on the side where it meets the rear cover.

10. An air filter device for a hydrogen-ammonia internal combustion engine according to claim 1, characterized in that, The outer side of the rear cover is integrally formed with multiple buckles and second fixing ears. The edge of the front cover is integrally formed with a fixing buckle and a first fixing ear that cooperate with the buckles and second fixing ears provided on the rear cover. The buckles and the fixing buckle are fastened to each other and fixed. The first fixing ear and the second fixing ear abut against each other and are fixed. An air inlet pipe is integrally formed in the middle of the front cover on the side away from the rear cover. An air distribution mesh is installed on the inner side of the front cover on the side that is connected to the rear cover through multiple integrally formed mounting platforms. The side of the air distribution mesh away from the filter element and the inner side of the front cover form an air distribution cavity.

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