Marine dual-fuel engine air inlet pipe

Abstract

The utility model discloses a marine dual-fuel engine air inlet pipe which comprises an air inlet pipe assembled and communicated on an engine cylinder cover, and the air inlet pipe is communicated with a natural gas inlet pipe. The gas inlet pipe comprises a plurality of gas inlet pipe units which are detachably assembled and connected in sequence, and the natural gas inlet pipe comprises a plurality of natural gas inlet pipe units which are detachably assembled and connected in sequence; the gas inlet pipe unit is communicated with the natural gas inlet pipe unit; a gas mixing mechanism lined in a pipeline cavity is fixedly connected in the gas inlet pipe unit; the gas mixing mechanism comprises a plurality of gas mixing units which are sequentially and integrally formed, each gas mixing unit comprises two symmetrically arranged reducer pipes, and the reducer pipes are integrally formed; and the small-caliber mouth parts of the reducer pipes are butted together. According to the device, natural gas and air are fully mixed, and after mixed gas is fully mixed before entering the engine cylinder body, the combustion efficiency of the mixed gas in the engine cylinder body is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of dual-fuel engines, and particularly relates to an intake pipe of a marine dual-fuel engine. Background Art

[0002] For a long time, ship engines have mainly burned liquid petroleum fuels. However, with the continuous reduction of petroleum reserves and the increasingly severe environmental pollution, energy conservation and emission reduction have received extensive attention. As a clean, reliable and rich in reserves high-quality fuel, natural gas has the characteristics of high calorific value, good anti-knock performance, high ignition temperature, etc., and significantly reduces the emissions of harmful substances compared with diesel engines, especially particulate matter emissions. Therefore, it is rapidly becoming the main substitute for petroleum. Diesel / natural gas dual-fuel engines use natural gas and diesel as fuels, and have good emission performance, power performance and economy, and are currently the focus of the development of ship engines.

[0003] The development of diesel / natural gas dual-fuel engines is to transform on the basis of diesel engines. The original fuel supply system, gas distribution system, etc. remain unchanged, and a natural gas supply system is added. Natural gas needs to have a passage to enter the diesel engine. However, the current intake pipe of the diesel engine cannot meet the intake demand of natural gas. Specifically, during the operation of the diesel engine, the engine draws air and natural gas into the diesel engine and burns to generate kinetic energy for work.

[0004] However, it is found in the actual operation process that due to the low mixing degree of natural gas and air when they are drawn into the cylinder, there is a defect of incomplete combustion. The specific reason is that due to the different densities of natural gas and air, during the process of being rapidly drawn into the cylinder of the engine, the gases cannot be fully mixed, resulting in the mixing degree of natural gas and air entering the engine cylinder body being constantly in a changing state, and thus the combustion effect is not good. Summary of the Utility Model

[0005] Based on the above background, the purpose of the utility model is to provide an intake pipe of a marine dual-fuel engine.

[0006] To achieve the above purpose, the utility model adopts the following technical solutions:

[0007] An intake pipe of a marine dual-fuel engine, comprising an intake pipe assembled and connected to the engine cylinder head, and the intake pipe is connected to an intake natural gas pipe;

[0008] The intake pipe comprises a plurality of intake pipe units detachably assembled and connected in sequence, and the intake natural gas pipe comprises a plurality of intake natural gas pipe units detachably assembled and connected in sequence;

[0009] The intake pipe unit and the intake natural gas pipe unit are respectively connected in a communicating manner; a gas mixing mechanism lined in the pipe cavity is fixedly connected inside the intake pipe unit;

[0010] The gas mixing mechanism includes a number of gas mixing units integrally formed in sequence. Each gas mixing unit includes two reduced-diameter pipes symmetrically arranged, and the reduced-diameter pipes are integrally formed between them.

[0011] The mouths of the reduced-diameter pipes with smaller diameters are butted together.

[0012] Preferably, the gas mixing mechanism is connected to the natural gas inlet pipe unit through a number of connecting pipes.

[0013] The inlet end of the connecting pipe is connected to the reduced-diameter pipe.

[0014] The outlet end of the connecting pipe penetrates through the inlet pipe unit.

[0015] A spray valve is assembled and connected to the connecting pipe, and the inlet end of the spray valve is connected to the natural gas inlet pipe unit.

[0016] Preferably, the shape of the reduced-diameter pipe is conical.

[0017] Preferably, the inlet pipe units are connected by pipe flanges.

[0018] The natural gas inlet pipe units are connected by pipe flanges.

[0019] Preferably, the gas mixing mechanism includes a first gas mixing unit located at the inlet end of the inlet pipe unit. The first gas mixing unit is integrally formed with a second gas mixing unit, the second gas mixing unit is integrally formed with a third gas mixing unit, and the third gas mixing unit is integrally formed with a fourth gas mixing unit.

[0020] The fourth gas mixing unit is integrally formed with a fifth gas mixing unit, the fifth gas mixing unit is integrally formed with a sixth gas mixing unit, the sixth gas mixing unit is integrally formed with a seventh gas mixing unit, and the seventh gas mixing unit is integrally formed with an eighth gas mixing unit.

[0021] The outlet end of the eighth gas mixing unit is located at the outlet end of the inlet pipe unit.

[0022] Preferably, an elastic flow disturbing mechanism is fixedly connected to the connection position of the reduced-diameter pipe.

[0023] Preferably, the elastic flow disturbing mechanism includes a ring seat fixedly connected to the connection position of the reduced-diameter pipe.

[0024] A number of flow disturbing vanes are fixedly connected to the inner side wall of the ring seat and extend towards the reduced-diameter pipes on both sides respectively.

[0025] Preferably, the flow disturbing vane includes a downward bending part fixedly connected to the ring seat, and the downward bending part is integrally formed with an upward extending part that is inclined upwards.

[0026] Preferably, the spoiler vane is made of silicon steel sheet.

[0027] The utility model has the following beneficial effects:

[0028] 1. During the working process, when the gas passes through the reducer, the radius of the gas channel is constantly changing, and thus the flow rate of the gas is constantly changing (the narrower the channel, the greater the flow rate of the gas)

[0029] 2. During the working process, when the injection valve is opened, the natural gas with a certain pressure enters the intake pipe unit and mixes with the air. During the process of passing through the first mixing unit to the eighth mixing unit in the above manner, the flow rate of the gas is in a constantly changing state due to the continuous change in the diameter of the channel, thereby increasing the degree of mixing between the gases during the passage of two gases of different densities. Specifically, since the flow rate of the gas is proportional to the gas pressure, the continuous change of the gas pressure and flow rate promotes other mixing, thereby achieving full mixing of the natural gas and the air when they enter the engine cylinder.

[0030] 3. During the working process, due to the mixed gas with constantly changing speed and pressure, the elastic material spoiler vanes are constantly moved, especially when the airflow is about to pass through the small-diameter mouth of the reducer. At this time, the moving speed of the spoiler vanes is the largest, and the moving amplitude of the spoiler vanes is larger, so that the effect of stirring the airflow is more significant, and the airflow is fully mixed in this way. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0032] Figure 1 It is a schematic diagram of the overall structure in which the air intake pipe and the natural gas intake pipe are connected to the engine cylinder head in the embodiment of the utility model;

[0033] Figure 2 This is a schematic diagram of the structure of the gas mixing mechanism in the embodiment of the utility model;

[0034] Figure 3 It is a schematic diagram of the structure of the first gas mixing unit to the eighth gas mixing unit in the embodiment of the utility model;

[0035] Figure 4 This is a schematic diagram of the structure in which the gas mixing mechanism is installed in the intake natural gas pipe in the embodiment of the utility model;

[0036] Figure 5 This is a schematic structural view of the elastic flow disturbing mechanism fixedly connected in the gas mixing unit in an embodiment of the present utility model;

[0037] Figure 6 This is a schematic structural view of the elastic flow disturbing mechanism in an embodiment of the present utility model.

[0038] The realization of the purpose, functional characteristics and advantages of the present utility model will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0039] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0040] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present utility model are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0041] In addition, in the present utility model, descriptions such as "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present utility model.

[0042] Embodiment 1

[0043] As Figures 1-6 shown, a marine dual-fuel engine intake pipe includes an intake pipe assembled and connected to an engine cylinder head 1 (specifically, in the same manner as the existing method, the outlet end of the intake pipe is connected to the engine cylinder head through an intake manifold 11), and the intake pipe is connected to a natural gas inlet pipe.

[0044] Specifically, the intake pipe includes a number of intake pipe units 2 that are detachably assembled and connected in sequence (the intake pipe units 2 are detachably connected in sequence through flanges), and the natural gas intake pipe includes a number of natural gas intake pipe units that are detachably assembled and connected in sequence (similarly, they are detachably assembled through pipe flanges in sequence).

[0045] The above-mentioned intake pipe unit 2 and the natural gas intake pipe unit 3 are respectively communicated; a gas mixing mechanism 4 lined in the pipe cavity is fixedly connected inside the intake pipe unit 2.

[0046] During the intake process through the gas mixing mechanism 4, when the natural gas in the intake pipe unit 2 is pumped into the intake pipe unit 2, the gas mixing mechanism 4 continuously mixes the gas, so as to achieve a high mixing degree of the natural gas and air entering the engine cylinder body, thereby improving the combustion efficiency.

[0047] Specifically, the gas mixing mechanism 4 includes a number of gas mixing units integrally formed in sequence (specifically, the number of gas mixing units is eight, distributed from the intake end to the outlet end inside the intake pipe unit 2. Specifically, the gas mixing mechanism 4 includes a first gas mixing unit 41 located at the intake end of the intake pipe unit 2, the first gas mixing unit 41 is integrally formed with a second gas mixing unit 42, the second gas mixing unit 42 is integrally formed with a third gas mixing unit 43, and the third gas mixing unit 43 is integrally formed with a fourth gas mixing unit 44; the fourth gas mixing unit 44 is integrally formed with a fifth gas mixing unit 45, the fifth gas mixing unit 45 is integrally formed with a sixth gas mixing unit 46, the sixth gas mixing unit 46 is integrally formed with a seventh gas mixing unit 47, and the seventh gas mixing unit 47 is integrally formed with an eighth gas mixing unit 48; the outlet end of the eighth gas mixing unit 48 is located at the outlet end of the intake pipe unit 2).

[0048] The specific structure of the gas mixing unit is:

[0049] The gas mixing unit includes two symmetrically arranged variable-diameter pipes A, and the variable-diameter pipes A are integrally formed between them.

[0050] Specifically, the shape of the variable-diameter pipe A is conical, and the side with the smaller mouth radius is butted together (that is, the mouths with smaller diameters of the variable-diameter pipes A are butted together).

[0051] During the working process, when the gas passes through the variable-diameter pipe A, since the channel radius of the gas is in a continuously changing state, the flow rate of the gas continuously changes (the narrower the channel, the greater the flow rate of the gas).

[0052] The above-mentioned mixing mechanism 4 is connected to the natural gas inlet pipe unit 3 through two connecting pipes 21 (the two connecting pipes 21 are spaced apart on the left and right); the air inlet end of the connecting pipe 21 is connected to the reducer A; the air outlet end of the connecting pipe 21 passes through the air inlet pipe unit 2; an injection valve 31 is installed and connected to the connecting pipe 21, and the air inlet end of the injection valve 31 is connected to the natural gas inlet pipe unit 3.

[0053] During operation, when the injection valve is opened, natural gas with a certain pressure enters the intake pipe unit 2 and mixes with the air. During the process of passing through the first mixing unit to the eighth mixing unit in the above manner, the flow rate of the gas is in a constantly changing state due to the continuous change in the diameter of the channel, thereby increasing the degree of mixing between the gases during the passage of two gases of different densities. Specifically, since the flow rate of the gas is proportional to the gas pressure, the continuous change in gas pressure and flow rate promotes other mixing, thereby achieving full mixing of natural gas and air when they enter the engine cylinder.

[0054] Example 2

[0055] like Figures 1-6 As shown, in order to further increase the mixing degree between the gases, the connection position of the reducer A is fixedly connected with an elastic spoiler mechanism (i.e., the docking position of the small-diameter mouth of the reducer A).

[0056] Specifically, the elastic spoiler mechanism includes a ring seat 52 fixedly connected to the connection position of the reducer A; a plurality of spoiler vanes 51 extending toward the reducers A on both sides are fixedly connected to the inner wall of the ring seat 52. The spoiler vanes 51 are made of thin silicon steel sheets and have high elasticity.

[0057] Its shape is: the spoiler blade 51 includes a lower bending part fixedly connected to the ring seat 52, and the lower bending part is integrally formed with an upper extension part inclined upward. During operation, due to the mixed gas with constantly changing speed and pressure, the spoiler blade 51 made of elastic material is constantly moved, especially when the airflow is about to pass through the small-caliber mouth docking position of the reducer A, the moving speed of the spoiler blade 51 is the largest, and the moving amplitude of the spoiler blade 51 is larger, and the effect of stirring the airflow is more significant, and the airflow is fully mixed in this way.

[0058] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. An intake pipe for a marine dual-fuel engine, characterized in that, It includes an intake pipe assembled and connected to the engine cylinder head, and the intake pipe is connected to a natural gas intake pipe; The intake pipe includes a number of intake pipe units detachably assembled and connected in sequence, and the natural gas intake pipe includes a number of natural gas intake pipe units detachably assembled and connected in sequence; The intake pipe unit and the natural gas intake pipe unit are respectively connected in a communicating manner; a gas mixing mechanism lined in the pipe cavity is fixedly connected inside the intake pipe unit; The gas mixing mechanism includes a number of gas mixing units integrally formed in sequence, and each gas mixing unit includes two reduced-diameter pipes symmetrically arranged, and the reduced-diameter pipes are integrally formed between them; The mouths of the reduced-diameter pipes with smaller diameters are butted together.

2. The intake pipe of the marine dual-fuel engine according to claim 1, wherein The gas mixing mechanism is connected to the natural gas intake pipe unit through a number of connecting pipes; The intake end of the connecting pipe is connected to the reduced-diameter pipe; The outlet end of the connecting pipe penetrates through the intake pipe unit; A spray valve is assembled and connected to the connecting pipe, and the intake end of the spray valve is connected to the natural gas intake pipe unit.

3. The intake pipe of the marine dual-fuel engine according to claim 1, characterized in that, The shape of the reduced-diameter pipe is conical.

4. The intake pipe of the marine dual-fuel engine according to claim 1, characterized in that, The intake pipe units are connected by pipe flanges; The natural gas intake pipe units are connected by pipe flanges.

5. The intake pipe of the marine dual-fuel engine according to claim 1, characterized in that, The gas mixing mechanism includes a first gas mixing unit located at the intake end of the intake pipe unit. The first gas mixing unit is integrally formed with a second gas mixing unit, the second gas mixing unit is integrally formed with a third gas mixing unit, and the third gas mixing unit is integrally formed with a fourth gas mixing unit; The fourth gas mixing unit is integrally formed with a fifth gas mixing unit, the fifth gas mixing unit is integrally formed with a sixth gas mixing unit, the sixth gas mixing unit is integrally formed with a seventh gas mixing unit, and the seventh gas mixing unit is integrally formed with an eighth gas mixing unit; The outlet end of the eighth gas mixing unit is located at the outlet end of the intake pipe unit.

6. The intake pipe of the marine dual-fuel engine according to claim 1, characterized in that, An elastic flow disturbing mechanism is fixedly connected to the connection position of the reduced-diameter pipe.

7. The intake pipe of the marine dual-fuel engine according to claim 6, characterized in that, The elastic flow disturbing mechanism includes a ring seat fixedly connected to the connection position of the reduced-diameter pipe; A number of flow disturbing vanes respectively extending towards the reduced-diameter pipes on both sides are fixedly connected to the inner side wall of the ring seat.

8. The intake pipe of the marine dual-fuel engine according to claim 7, characterized in that, The flow disturbing vane includes a lower bending part fixedly connected to the ring seat, and the lower bending part is integrally formed with an upper extending part inclined upwards.

9. The intake pipe of the marine dual-fuel engine according to claim 7, characterized in that, The material of the flow disturbing vane is silicon steel sheet material.

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