Diesel engine silencing system and diesel engine

Abstract

The invention provides a diesel engine noise elimination system and a diesel engine, and belongs to the field of diesel engines, the diesel engine noise elimination system comprises a shell, an air inlet cavity, a noise elimination cavity, a resonant cavity, an air outlet cavity and a reflection cylinder, the reflection cylinder is arranged in the air inlet cavity and fixedly connected with an annular partition plate, the reflection cylinder is provided with a first sound absorption layer, and an air inlet pipe extends to the inner side of the reflection cylinder; first micropores are formed in the surface of the air inlet pipe; a plurality of horn mouth structural members are arranged in the air inlet cylinder, and the large-diameter ends of the horn mouth structural members face the air outlet pipe; second micropores are evenly distributed in the side, close to the air inlet pipe, of the air outlet cylinder and communicate with an air outlet cavity. According to the diesel engine noise elimination system, low-frequency-band noise is weakened through the first micro-hole position, then medium-frequency-band noise and high-frequency-band noise are weakened through the first sound absorption layer, the medium-frequency-band noise and the low-frequency-band noise are weakened through step-by-step expansion and consumption of sound wave energy by means of the horn mouth structural part, then sound waves with specific frequency are eliminated through the resonant cavity, and finally sound waves with specific frequency are eliminated at the second micro-hole position. And eliminating the low-frequency-band noise again.

Description

Technical Field

[0001] The present invention relates to the technical field of muffler devices, and in particular to a diesel engine muffler system and a diesel engine. Background Art

[0002] The air noise generated by marine diesel engine exhaust also has a great impact on the environment, especially in some places or scientific research work scenes that are sensitive to air noise. The diesel engine outlet noise will be transmitted to the surrounding and underwater through the air and pipes, seriously affecting the acoustic environment in these cabins and the ocean. Diesel engine emission noise must be strictly controlled. The measure usually taken is to add a reliable muffler device at the diesel engine outlet to keep the surrounding and underwater radiated noise within a controllable range.

[0003] Existing diesel engine intake mufflers typically achieve their noise reduction goals by providing an expansion chamber within the airflow pipe and lining the inner walls of the expansion chamber with fiber cotton or porous sound-absorbing material. This chamber converts the sound energy propagating through the pipe into heat energy within the expansion chamber. However, the frequency range of noise reduction achieved by this type of diesel engine intake muffler is often limited by the performance of the sound-absorbing material, and it is unable to effectively reduce low-frequency noise within 1000Hz. Summary of the Invention

[0004] In view of the above problems, the present invention provides a diesel engine muffler system and a diesel engine.

[0005] A diesel engine muffler system comprises: a shell, an air inlet pipe and an air outlet pipe are respectively arranged on both sides, and an annular partition, a first partition and a second partition are sequentially arranged on the inner side of the shell to separate the shell into an air inlet chamber, a muffler chamber, a resonance chamber and an air outlet chamber, the air inlet chamber is connected to the air inlet pipe, and the air outlet chamber is connected to the air outlet pipe; a reflective cylinder is arranged in the air inlet chamber and fixedly connected to the inner wall of the annular partition, a first sound-absorbing layer is arranged on the inner wall of the reflective cylinder, the air inlet pipe extends to the inner side of the reflective cylinder, and first micropores are evenly arranged on the surface of the air inlet pipe; a plurality of air inlet cylinders are arranged on the inner side of the shell and are arranged Placed on the outside of the reflecting cylinder, any air inlet cylinder passes through the annular partition, the first partition, and the second partition in sequence, and the two ends are respectively connected to the air inlet cavity and the air outlet cavity, and a resonance hole is opened on the air inlet cylinder, and the resonance hole is opened between the first partition and the second partition. The air inlet cylinder also includes a plurality of bell-mouth structures arranged at equal intervals in sequence, and the large-diameter end of the bell-mouth structure faces the air outlet pipe; the air outlet cylinder is arranged on the inner side of the plurality of air inlets, one end is sealed and fixed by the second partition, and the other end is connected to the air outlet pipe. Second micropores are distributed on the side of the air outlet cylinder close to the air inlet pipe, and the second micropores are connected to the air outlet cavity.

[0006] In a preferred embodiment, the bell-mouth structure includes: a cylindrical opening section, which is arranged in the air intake cylinder and does not contact the inner wall of the air intake cylinder; and a bell-mouth opening section, which is integrally arranged on the side of the cylindrical section away from the air intake pipe and fixedly connected to the air intake cylinder.

[0007] In a preferred embodiment, any flared structural member is formed by fixing metal thin plates at equal intervals from the inside to the outside, and third micro-holes are provided on any metal thin plate layer.

[0008] In a preferred embodiment, the diesel engine silencing system further includes: a second sound-absorbing layer disposed on both the inner and outer sides of the air outlet cylinder, as well as between the flared structural member and the air inlet cylinder.

[0009] In a preferred embodiment, the diesel engine silencing system further includes: a plurality of atomizing connecting pipes, any one of which is disposed on one side of the air inlet cylinder, is arranged parallel to the central axis of the air inlet cylinder, has one end closed and the other end passing through the housing, and the atomizing connecting pipe communicates with the air inlet cylinder through a diversion hole, and the diversion hole is disposed on one side of the flared structural member.

[0010] In a preferred embodiment, the air inlet cylinder further includes: a flared section disposed on one side of a plurality of flared structural members and close to the air outlet pipe.

[0011] In a preferred embodiment, the diesel engine silencing system further includes: a plurality of silencing sleeves, any one of which is disposed outside the flared structural member and inside the air inlet cylinder, and each silencing sleeve includes an inner ring, two horizontal partition plates, and a plurality of vertical partition plates. The two horizontal partition plates are fixed on both sides of the inner ring, the vertical partition plates are fixed on the inner ring and the horizontal partition plates at equal intervals, and a third sound-absorbing layer is provided on the horizontal partition plates.

[0012] A diesel engine includes a diesel engine silencing system.

[0013] 1. For the air flow and sound waves of the diesel engine silencing system of the present application, they enter the air inlet cavity from the first micro-holes of the air inlet pipe, weaken the low-frequency band noise at the position of the first micro-holes, and then, after reflecting and absorbing part of the sound wave energy by the first sound-absorbing layer, weaken the medium- and high-frequency band noise, and then enter the air inlet cylinder. After passing through the flared structural member, they expand step by step, consume the sound wave energy, weaken the medium- and low-frequency band noise, then pass through the resonance cavity, generate a damping effect, weaken or eliminate the sound waves of specific frequencies, and finally enter the air outlet pipe, where the low-frequency band noise is eliminated again at the position of the second micro-holes.

[0014] 2. Through the design of the first micro-holes, the second micro-holes, and the third micro-holes, the diesel engine silencing system of the present application can effectively reduce and eliminate the low-frequency band noise. Description of the Drawings

[0015] Read the following description of the exemplary embodiments with reference to the accompanying drawings, and other features, characteristics and advantages of the present invention will become clear. The drawings incorporated in the specification and forming a part of the specification illustrate embodiments of the present invention and, together with the description, are used to explain the principles of the present invention. In these drawings, like reference numerals are used to represent like elements. The drawings in the following description are some embodiments of the present invention, not all embodiments. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 Structural diagrams of Embodiments 1 - 4 of the diesel engine muffler system of the present invention;

[0017] Figure 2 Cross-sectional views of Embodiments 5 - 8 of the diesel engine muffler system of the present invention;

[0018] Figure 3 Internal structural diagrams of Embodiments 5 - 8 of the diesel engine muffler system of the present invention;

[0019] Figure 4 Structural diagram of the bellmouth structural member of the diesel engine muffler system of the present invention;

[0020] Figure 5 Cross-sectional view at the A - A position of the diesel engine muffler system of the present invention;

[0021] Figure 6 Cross-sectional view at the B - B position of the diesel engine muffler system of the present invention;

[0022] Figure 7 Enlarged view of position C of the diesel engine muffler system of the present invention;

[0023] Figure 8 Structural diagram of the muffler sleeve of the diesel engine muffler system of the present invention;

[0024] Figure 9 Structural diagram of the atomizing connecting pipe and the intake cylinder of the present invention;

[0025] Figure 10 External view of the diesel engine muffler system of the present invention.

[0026] In the figure:

[0027] 10. Housing; 11. Intake pipe; 12. Exhaust pipe; 13. Annular partition; 14. First partition; 15. Second partition; 100. Intake cavity; 101. Silencing cavity; 102. Resonance cavity; 103. Exhaust cavity; 131. Reflecting cylinder; 132. First sound-absorbing layer; 111. First micropore; 20. Intake cylinder; 21. Resonance hole; 22. Flared mouth structural member; 30. Exhaust cylinder; 31. Second micropore; 221. Cylindrical opening section; 222. Flared opening section; 223. Metal thin plate layer; 224. Third micropore; 200. Second sound-absorbing layer; 40. Atomization connecting pipe; 41. Diversion hole; 23. Flared section; 50. Silencing sleeve; 51. Inner ring; 52. Partition; 53. Vertical partition; 201. Third sound-absorbing layer; 133. Silencing ring. Detailed implementation manner

[0028] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other arbitrarily.

[0029] The diesel engine silencing system and the diesel engine will be described in detail below with reference to the accompanying drawings and embodiments.

[0030] Embodiment 1

[0031] A diesel engine silencing system, comprising: a housing 10, with an intake pipe 11 and an exhaust pipe 12 respectively arranged on both sides, and an annular partition 13, a first partition 14, and a second partition 15 are sequentially arranged inside the housing 10, dividing the housing 10 into an intake cavity 100, a sound absorption cavity 101, a resonance cavity 102, and an exhaust cavity 103. The intake cavity 100 is communicated with the intake pipe 11, and the exhaust cavity 103 is communicated with the exhaust pipe 12; a reflection cylinder body 131, arranged inside the intake cavity 100, fixedly connected to the inner wall of the annular partition 13. The inner wall of the reflection cylinder body 131 is provided with a first sound absorption layer 132. The intake pipe 11 extends to the inside of the reflection cylinder body 131, and first micropores 111 are evenly arranged on the surface of the intake pipe 11; a plurality of intake cylinders 20, arranged inside the housing 10 and outside the reflection cylinder body 131. Any one of the intake cylinders 20 sequentially passes through the annular partition 13, the first partition 14, and the second partition 15, and both ends are respectively communicated with the intake cavity 100 and the exhaust cavity 103. A resonance hole 21 is opened on the intake cylinder 20, and the resonance hole 21 is opened between the first partition 14 and the second partition 15. The intake cylinder 20 further includes a plurality of flared structural members 22 arranged at equal intervals in sequence. The large-diameter end of the flared structural member 22 faces the exhaust pipe 12; an exhaust cylinder 30, arranged inside the plurality of intake cylinders 20, one end is fixedly sealed through the second partition 15, and the other end is communicated with the exhaust pipe 12. Second micropores 31 are evenly distributed on the side of the exhaust cylinder 30 close to the intake pipe 11, and the second micropores 31 are communicated with the exhaust cavity 103.

[0032] During operation, air flow and sound waves enter the intake cavity 100 from the first micropores 111 of the intake pipe 11, the low-frequency band noise is weakened at the position of the first micropores 111, and then after part of the sound wave energy is reflected and absorbed by the first sound absorption layer 132, the medium- and high-frequency band noises are weakened. Then it enters the intake cylinder 20, passes through the flared structural member 22, expands step by step, consumes the sound wave energy, and weakens the medium- and low-frequency band noises. Then it passes through the resonance cavity 102 to generate a damping effect, weakening or eliminating sound waves of specific frequencies. Finally, it enters the exhaust pipe 12, and at the position of the second micropores 31, the low-frequency band noise is eliminated again.

[0033] Among them, the housing 10, the annular partition 13, and the reflection cylinder body 131 divide the central plane of the intake cavity 100 into a "T" shape structure.

[0034] Among them, the first micropores 111 are distributed inside the reflection cylinder body 131.

[0035] Among them, the perforation positions of the intake pipe 11 and the exhaust cylinder 30 are pure metal foils with a thickness less than 1 mm. The diameters of the first micropores 111 and the second micropores 31 are less than 1 mm, and the perforation rate is 1% - 3%.

[0036] Among them, there are a total of four intake cylinders 20 in the diesel engine silencing system.

[0037] Among them, the first sound-absorbing layer 132 can be glass fiber cotton, aluminum silicate rock wool or other porous sound-absorbing materials.

[0038] Embodiment 2

[0039] Embodiment 2 is a specific description of Embodiment 1. The flared structure member 22 may include: a cylindrical opening section 221 disposed inside the air intake cylinder 20 and not in contact with the inner wall of the air intake cylinder 20; a flared opening section 222 integrally disposed on one side of the cylindrical section away from the intake pipe 11 and fixedly connected to the air intake cylinder 20.

[0040] Among them, there is a certain gap between the cylindrical opening sections 221 and the flared opening sections 222 of two adjacent flared structure members 22, which can enable the sound wave energy to enter between the flared structure member 22 and the air intake cylinder 20 through this gap, and then gradually consume the sound wave energy.

[0041] Embodiment 3

[0042] Embodiment 3 is an improvement over Embodiment 1. The improvement includes: any flared structure member 22 is formed by fixing metal thin plates 223 at equal intervals from the inside to the outside, and a third micropore 224 is provided on any metal thin plate 223.

[0043] Among them, when sound waves enter between the metal thin plates 223, the low-frequency band noise can be eliminated through the third micropores 224 provided on the metal thin plates 223.

[0044] Among them, the metal thin plate 223 is made of a pure metal thin plate with a thickness less than 1 mm, the aperture of the third micropore 224 is less than 1 mm, and the perforation rate is 1% - 3%.

[0045] Embodiment 4

[0046] Embodiment 4 is an improvement over Embodiment 1. The improvement includes that the diesel engine silencing system further includes: a second sound-absorbing layer 200 disposed on both the inner and outer sides of the air outlet cylinder 30, as well as between the flared structure member 22 and the air intake cylinder 20.

[0047] By providing the second sound-absorbing layer 200, the medium and high frequency noise of the diesel engine is eliminated at the positions on both the inner and outer sides of the air outlet cylinder 30, as well as between the flared structure member 22 and the air intake cylinder 20.

[0048] Among them, the second sound-absorbing layer 200 can be glass fiber cotton, aluminum silicate rock wool or other porous sound-absorbing materials.

[0049] Embodiment 5

[0050] Embodiment 5 is an improvement over Embodiment 1. The improvements include: The diesel engine silencing system further includes: a plurality of atomizing connecting pipes 40. Any one of the atomizing connecting pipes 40 is arranged on one side of the intake cylinder 20, parallel to the central axis of the intake cylinder 20, with one end closed and the other end passing through the housing 10. The atomizing connecting pipe 40 communicates with the intake cylinder 20 through a diversion hole 41, and the diversion hole 41 is arranged on one side of the flared structure member 22.

[0051] During operation, an atomizing connecting pipe 40 is arranged on one side of the intake cylinder 20 and communicates with the intake cylinder 20. By introducing atomized urea solution, harmful gases in the exhaust gas can be neutralized during the exhaust process of the diesel engine.

[0052] Among them, the atomized urea solution enters through the atomizing connecting pipe 40 and reacts obliquely with the exhaust gas through the flared structure member 22. The diameter of the diversion hole 41 gradually decreases from the intake pipe 11 to the exhaust pipe 12, thereby controlling the input amount of the atomized urea solution and improving the mixing uniformity of the exhaust gas and the atomized urea solution.

[0053] Among them, the diversion hole 41 can be installed between the atomizing connecting pipe 40 and the intake cylinder 20 through a partition plate and formed by opening holes in the partition plate.

[0054] Embodiment 6

[0055] Embodiment 6 is an improvement over Embodiment 1. The improvements include: The intake cylinder 20 further includes: a flared section 23, arranged on one side of a plurality of flared structure members 22 and close to the exhaust pipe 12.

[0056] Among them, by setting the flared section 23, a sudden change interface is generated, further weakening the medium and low frequency band noise. 100

[0057] Embodiment 7

[0058] Embodiment 7 is an improvement over Embodiment 1. The improvements include: The diesel engine silencing system further includes: a plurality of silencing sleeves 50. Any one of the silencing sleeves 50 is arranged outside the flared structure member 22 and inside the intake cylinder 20. The silencing sleeve 50 includes an inner ring 51, two horizontal partition plates 52, and a plurality of vertical partition plates 53. The two horizontal partition plates 52 are fixed on both sides of the inner ring 51, and the vertical partition plates 53 are fixed on the inner ring 51 and the horizontal partition plates 52 at equal intervals, and a third sound absorption layer 201 is arranged on the horizontal partition plate 52.

[0059] Among them, by arranging the silencing sleeve 50 outside the flared structure member 22, when sound waves enter the silencing sleeve 50, due to volume expansion, the medium and low frequency band noise is weakened. At the same time, the setting of the third sound absorption layer 201 on the vertical partition plate 53 increases the area of the sound absorption cotton and improves the weakening efficiency of the high frequency band noise.

[0060] Among them, a fourth micropore can be provided on the vertical partition plate 53 to weaken the medium and low-frequency energy entering the muffling sleeve 50.

[0061] Among them, the outer diameter of the muffling sleeve 50 is 8 / 10 - 9 / 10 of the diameter of the intake cylinder 20. When the atomized urea solution enters the intake cylinder 20, a part of the solution will diffuse along the gap between the intake cylinder 20 and the muffling sleeve 50, and then enter the inner side of the intake cylinder 20 from the gap between the adjacent vertical partition plates 53 to react with the exhaust gas, so that the atomized urea solution can enter the horn-shaped structural member 22 evenly, improving the mixing uniformity of the tail gas and the atomized urea solution.

[0062] Among them, the third sound-absorbing layer 201 can be glass fiber cotton, aluminum silicate rock wool or other porous sound-absorbing materials.

[0063] Embodiment 8

[0064] Embodiment 8 is an improvement over Embodiment 1. The improvements include: The diesel engine muffling system further includes: a muffling ring 133, which is arranged at equal intervals inside the reflection cylinder body 131, and the large-diameter end faces the exhaust pipe 12.

[0065] Among them, when the sound wave enters the inside of the reflection cylinder body 131, due to the effect of the muffling ring 133, the volume of the sound wave becomes larger, thereby weakening the sound wave energy and weakening the medium and low-frequency band noise.

[0066] A diesel engine includes a diesel engine muffling system.

[0067] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that an article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such article or device. Without further limitation, the elements defined by the statement "include..." do not exclude the existence of additional identical elements in the article or device including the elements.

[0068] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. The present invention has only been described in detail with reference to the preferred embodiments. Those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and all should be covered within the scope of the claims of the present invention.

Claims

1. A diesel engine silencing system, characterized in that, Comprising: A housing (10) with an intake pipe (11) and an exhaust pipe (12) respectively arranged on both sides, and an annular partition (13), a first partition (14), and a second partition (15) are sequentially arranged inside the housing (10), separating the housing (10) into an intake cavity (100), a silencing cavity (101), a resonance cavity (102), and an exhaust cavity (103). The intake cavity (100) is communicated with the intake pipe (11), and the exhaust cavity (103) is communicated with the exhaust pipe (12); A reflection cylinder body (131) is arranged in the intake cavity (100) and fixedly connected to the inner wall of the annular partition (13). A first sound-absorbing layer (132) is arranged on the inner wall of the reflection cylinder body (131). The intake pipe (11) extends to the inside of the reflection cylinder body (131), and a first micropore (111) is uniformly arranged on the surface of the intake pipe (11); A plurality of intake cylinders (20) are arranged inside the housing (10) and outside the reflection cylinder body (131). Any one of the intake cylinders (20) sequentially passes through the annular partition (13), the first partition (14), and the second partition (15), and both ends are respectively communicated with the intake cavity (100) and the exhaust cavity (103). A resonance hole (21) is opened on the intake cylinder (20), and the resonance hole (21) is opened between the first partition (14) and the second partition (15). The intake cylinder (20) further includes a plurality of flared structure members (22) arranged at equal intervals in sequence, and the large-diameter end of the flared structure member (22) faces the exhaust pipe (12); An exhaust cylinder (30) is arranged inside the plurality of intake cylinders (20). One end is fixedly sealed through the second partition (15), and the other end is communicated with the exhaust pipe (12). Second micropores (31) are uniformly distributed on the side of the exhaust cylinder (30) close to the intake pipe (11), and the second micropores (31) are communicated with the exhaust cavity (103).

2. The diesel engine muffler system according to claim 1, characterized in that The flared structure member (22) includes: A cylindrical opening section (221) is arranged inside the intake cylinder (20) and does not contact the inner wall of the intake cylinder (20); A flared opening section (222) is integrally arranged on one side of the cylindrical section away from the intake pipe (11) and is fixedly connected to the intake cylinder (20).

3. The diesel engine silencing system according to claim 1, wherein Any one of the flared structure members (22) is fixedly formed by metal thin plate layers (223) at equal intervals from the inside to the outside, and a third micropore (224) is arranged on any one of the metal thin plate layers.

4. The diesel engine silencing system according to claim 1, wherein The diesel engine silencing system further includes: A second sound-absorbing layer (200) is arranged on both the inner and outer sides of the exhaust cylinder (30), and between the flared structure member (22) and the intake cylinder (20).

5. The diesel engine muffler system according to claim 2, characterized in that, The diesel engine silencing system further includes: A plurality of atomizing connecting pipes (40), any one of the atomizing connecting pipes (40) is arranged on one side of the intake cylinder (20), arranged parallel to the central axis of the intake cylinder (20), one end is closed, and the other end passes through the housing (10). The atomizing connecting pipe (40) is communicated with the intake cylinder (20) through a diversion hole (41), and the diversion hole (41) is arranged on one side of the flared structural member (22).

6. The diesel engine silencing system according to claim 2, characterized in that, The intake cylinder (20) further includes: A flared section (23) is arranged on one side of the plurality of flared structural members (22) and is arranged close to the exhaust pipe (12).

7. The diesel engine silencing system according to claim 5, wherein, The diesel engine silencing system further includes: A plurality of silencing sleeves (50), any one of the silencing sleeves (50) is arranged outside the flared structural member (22) and inside the intake cylinder (20). The silencing sleeve (50) includes an inner ring (51), two horizontal partitions (52), and a plurality of vertical partitions (53). The two horizontal partitions (52) are fixed on both sides of the inner ring (51), and the vertical partitions (53) are fixed on the inner ring (51) and the horizontal partitions (52) at equal intervals, and a third sound-absorbing layer (201) is arranged on the horizontal partition (52).

8. The diesel engine silencing system according to claim 5, characterized in that, The diesel engine silencing system further includes: A sound-absorbing ring (133) is arranged at equal intervals inside the reflection cylinder (131), and the large-diameter end faces the exhaust pipe (12).

9. A diesel engine, characterized in that, Including the diesel engine silencing system according to any one of claims 1-8.

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