A gas injection valve with air-assisted injection device

Abstract

The present application relates to a kind of gas injection valve with air assisted injection device, it relates to the field of engine, it includes the gas injection valve that can be arranged on engine cylinder sleeve, and air assisted injection device is arranged in gas injection valve, air assisted injection device can be passed with pressurized air.The present application uses more reasonable LNG injection mode, by more dispersedly injecting LNG into cylinder, the uniformity of LNG and air mixing can be effectively improved, so that natural gas and air mixing is more sufficient, and then improve the combustion process of natural gas in cylinder.

Description

Technical Field

[0001] This invention relates to the field of engines, and more particularly to a gas injection valve with an air-assisted injection device. Background Technology

[0002] To alleviate energy shortages and address environmental pollution, finding alternative energy sources and reducing harmful emissions have become two important research directions in the field of marine internal combustion engines. Natural gas has attracted widespread attention due to its lower emissions. As an alternative fuel, natural gas has advantages such as clean emissions, good economy, good anti-knock properties, high thermal efficiency, high safety, and abundant reserves.

[0003] Because gaseous natural gas occupies a large amount of space, making it inconvenient to transport and store, it is usually liquefied into liquefied natural gas (LNG) through pressurization and cooling and stored in storage tanks. LNG is widely used in marine engines. For large-bore, low-speed dual-fuel engines, LNG is typically injected directly into the cylinder through a gas injection valve. However, due to the large cylinder diameter, the injected LNG cannot be evenly distributed within the cylinder, resulting in localized over-enrichment and poor combustion performance. Summary of the Invention

[0004] The purpose of this invention is to solve the problems in the background art by providing a gas injection valve with an air-assisted injection device, which adopts a more reasonable LNG injection method to inject LNG into the cylinder in a more dispersed manner.

[0005] To achieve the above objectives, the present invention provides a gas injection valve with an air-assisted injection device, including a gas injection valve that can be disposed on an engine cylinder liner, and an air-assisted injection device disposed on the gas injection valve, wherein the air-assisted injection device can be supplied with pressurized air.

[0006] Preferably, the air-assisted injection device is located on the LNG flow path in the gas injection valve, and the direction of the pressurized air has a certain angle with the LNG flow path.

[0007] Preferably, the air-assisted injection device includes a scattering nozzle located at the outlet, a premixing chamber located on the LNG flow path and leading to the scattering nozzle, and a pressurized air pipeline leading to the premixing chamber.

[0008] Preferably, the premixing chamber has a horizontal cross-section that first increases, then decreases, and then increases again from top to bottom, corresponding to a first section, a second section, and a third section. The pressurized air pipeline leads to the first section, and the scattering nozzle is located at the bottom of the third section.

[0009] Preferably, the inner surface of the first section in the premixing chamber is flat, and the pressurized air pipeline is connected to the middle of the first section after being curved.

[0010] Preferably, there are two pressurized air pipelines, located on both sides of the first section.

[0011] Preferably, the connection between the second and third sections of the premixing chamber is a smooth transition.

[0012] Preferably, the gas injection valve includes a gas intake valve vertically connected to the top of the first section, and a gas intake pipe leading to the gas intake valve.

[0013] Preferably, the orientation of the gas intake pipe intersects the axial direction of the gas intake valve.

[0014] Preferably, the scattering nozzle has nozzles with different spray directions.

[0015] In summary, the present invention has the following beneficial technical effects:

[0016] This invention employs a more reasonable LNG injection method. By injecting LNG into the cylinder in a more dispersed manner, the uniformity of LNG mixing with air can be effectively improved, resulting in more thorough mixing of natural gas and air, thereby improving the combustion process of natural gas in the cylinder. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a gas injection valve with an air-assisted injection device according to the present invention;

[0018] Figure 2 This is a schematic diagram of the gas flow inside a gas injection valve with an air-assisted injection device according to the present invention.

[0019] Reference numerals in the attached diagram: 1. Gas injection valve; 2. Gas intake valve; 3. Gas intake line; 4. Pressurized air line; 5. Engine cylinder liner; 6. Premixing chamber; 7. Scattering nozzle. Detailed Implementation

[0020] 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.

[0021] like Figure 1As shown, this embodiment of the invention discloses a gas injection valve with an air-assisted injection device. The gas injection valve 1 is installed on the engine cylinder liner 5. The gas injection valve 1 mainly includes a gas intake valve 2 and a gas intake pipeline 3. The air-assisted injection device mainly includes a pressurized air pipeline 4, a premixing chamber 6, and a scattering nozzle 7.

[0022] LNG enters the gas injection valve 1 through the gas intake pipe 3. When the gas intake valve 2 is opened, the LNG enters the air-assisted injection device, and after being pressurized, it is injected into the cylinder through the scattering nozzle 7.

[0023] like Figure 1 As shown, a gas injection valve with an air-assisted injection device is installed on the cylinder liner. After the gas is injected through the injection valve, it enters the air-assisted injection device and first enters the premixing chamber 6. There are two pressurized air lines 4 in the air-assisted injection device, which can be connected to an external pressurized air device and lead into the premixing chamber 6.

[0024] The function of the air pipeline is to flexibly increase the injection pressure of LNG in the premixing chamber 6 by changing the pressure of the pressurized air, so as to change the gas injection distance according to different operating conditions of different engine models. If the engine cylinder diameter is large, the air pressure can be increased to increase the injection distance of the gas when it is injected from the auxiliary device, so as to avoid the gas not being able to reach the far end of the cylinder, causing uneven gas distribution and local over-rich gas.

[0025] In addition, a scattering nozzle 7 is installed at the outlet of the auxiliary device. The nozzle has nozzles with different spray directions. Its function is to spray LNG into the cylinder in a more dispersed manner through different spray directions, thereby further improving the uniformity of the gas and avoiding the problem of excessively rich gas in some parts of the cylinder.

[0026] like Figure 2 As shown, the gas flow process within the air-assisted injection device is as follows: Gas enters the gas injection valve 1 through the gas intake pipe 3, and when the gas intake valve 2 opens, it is injected into the premixing chamber 6 within the air-assisted injection device. Pressurized air is injected into the premixing chamber 6 through the pressurized air pipe 4, promoting the LNG to enter the scattering nozzle 7. The pressurized gas is then ejected through nozzles in different directions, entering the engine cylinders more dispersedly, allowing the LNG to be more evenly distributed within the cylinders.

[0027] In a two-stroke, large-bore, low-speed dual-fuel engine, LNG enters the gas injection valve 1 through the gas intake pipe 3. After the gas intake valve 2 opens, it is injected into the premixing chamber 6 of the air-assisted injection device. Depending on the cylinder diameter and operating conditions of different engine models, air at a pressure greater than the gas injection pressure is introduced into the top of the premixing chamber 6 to increase the gas injection pressure, thus solving the problem of uneven gas distribution caused by insufficient gas injection distance in engines with larger cylinder diameters. The gas is then injected into the cylinder from different directions through the scattering nozzle 7, further improving the problem of locally overly rich gas. In summary, a gas injection valve 1 with an air-assisted injection device can better and more evenly inject LNG into the cylinder, allowing the gas and air to mix thoroughly, resulting in more complete combustion and improving the combustion process of the mixture in the cylinder.

[0028] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gas injection valve with an air-assisted injection device, characterized in that, The system includes a gas injection valve (1) mounted on the engine cylinder liner (5) and an air-assisted injection device mounted on the gas injection valve (1), the air-assisted injection device being supplied with pressurized air; the air-assisted injection device includes a scattering nozzle (7) located at the outlet, a premixing chamber (6) located on the LNG flow path and leading to the scattering nozzle (7), and a pressurized air pipeline (4) leading to the premixing chamber (6); the premixing chamber (6) has a transverse cross-section that first increases, then decreases, and then increases again from top to bottom, corresponding to a first section, a second section, and a third section; the pressurized air pipeline (4) leads to the first section, and the scattering nozzle (7) is located at the bottom of the third section; the inner surface of the first section in the premixing chamber (6) is flat, and the pressurized air pipeline (4) is connected to the middle of the first section after being curved; there are two pressurized air pipelines (4), which are respectively located on both sides of the first section.

2. A gas injection valve with an air-assisted injection device according to claim 1, characterized in that, The air-assisted injection device is located on the LNG flow path in the gas injection valve (1), and the direction of the pressurized air has a certain angle with the LNG flow path.

3. A gas injection valve with an air-assisted injection device according to claim 1, characterized in that, The second and third sections of the premix chamber (6) are smoothly connected.

4. A gas injection valve with an air-assisted injection device according to claim 1, characterized in that, The gas injection valve (1) includes a gas intake valve (2) vertically connected to the top of the first section, and a gas intake pipe (3) leading to the gas intake valve (2).

5. A gas injection valve with an air-assisted injection device according to claim 4, characterized in that, The orientation of the gas intake pipe (3) intersects the axial direction of the gas intake valve (2).

6. A gas injection valve with an air-assisted injection device according to claim 1, characterized in that, The scattering nozzle (7) has nozzles with different spray directions.

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