CN215566238U

CN215566238U - Double-row jet hole type precombustion chamber

Info

Publication number: CN215566238U
Application number: CN202121681807.8U
Authority: CN
Inventors: 黄豪中; 王毅; 欧阳天成
Original assignee: Guangxi University
Current assignee: Guangxi University
Priority date: 2021-07-23
Filing date: 2021-07-23
Publication date: 2022-01-18
Anticipated expiration: 2031-07-23

Abstract

The utility model relates to a double-row jet hole type precombustion chamber, which comprises a precombustion chamber main body, an oil injector, a spark plug, a jet nozzle and a sealing ring, wherein the main body is provided with a plurality of jet holes; the fuel injector is arranged on the right side of the precombustion chamber main body and is used for injecting gasoline; the spark plug is arranged on the left side of the precombustion chamber main body and is used for igniting oil-gas mixture; the flame nozzle is in threaded connection with the precombustion chamber main body, and two spray holes are formed in the bottom of the flame nozzle, wherein the tangential spray holes are located above the radial spray holes. Compared with the traditional precombustion chamber, the structure of the precombustion chamber not only enlarges the flame propagation area, but also accelerates the flame propagation speed, ensures the flame stability, promotes the combustion process, shortens the combustion stagnation period of the mixed gas and increases the pressure rise rate; for the lean-burn mixture, the combustion pressure peak value can be increased, and effective ignition in the cylinder is guaranteed.

Description

Double-row jet hole type precombustion chamber

Technical Field

The utility model relates to the technical field of internal combustion engines, in particular to a double-row jet hole type precombustion chamber.

Background

In recent years, due to the requirements of national policy, oil consumption emission regulations are more stringent, and the traditional internal combustion engine is subjected to multiple challenges. In order to meet the requirements of energy conservation and emission reduction, the improvement of effective heat efficiency becomes the main development direction of the internal combustion engine. Under the prior art conditions, the effective thermal efficiency of gasoline engines can only be around 38%, and in order to achieve the target of 45% thermal efficiency, the energy distribution strategy of gasoline engines needs to be optimized, wherein the combustion mode is the most effective method. The precombustion chamber can realize rapid and stable combustion, can remarkably reduce the loss of pumping, heat transfer and combustion by matching with technologies such as Miller cycle, EGR (exhaust gas recirculation), lean burn and the like, has gradually been widely researched and applied to gasoline engines in recent years, and is considered to be one of the most promising technical routes of the future gasoline engines.

The ignition technology of the precombustion chamber ignites combustible mixed gas in a cavity of the precombustion chamber, so that high-temperature and high-pressure mixed gas in the precombustion chamber is sprayed to the main combustion chamber through the small holes, and ignition and combustion of the main combustion chamber are realized. The existing precombustion chamber mainly adopts small-sized jet holes to form jet flame to enter the combustion chamber, and although the flame propagation speed is high under the structure, the area of the sprayed flame is small and the flame is unstable; and has higher requirements on the turbulent kinetic energy of the main combustion chamber. Therefore, to further enhance the thermal efficiency of gasoline engines, there is a need to improve upon existing prechamber structures.

Disclosure of Invention

The utility model aims to provide a double-row jet hole type precombustion chamber, which accelerates the flame propagation speed, enlarges the flame propagation area, ensures the stability of flame propagation, promotes the combustion process, shortens the combustion stagnation period of mixed gas, increases the pressure rise rate, promotes the combustion pressure peak value and ensures effective ignition in a cylinder.

In order to solve the problems, the utility model provides a double-row jet hole type precombustion chamber, which comprises a precombustion chamber main body, an oil injector, a spark plug, a flame nozzle and a sealing ring; the fuel injector is arranged on the right side of the precombustion chamber main body and is used for injecting gasoline; the spark plug is arranged on the left side of the precombustion chamber main body and is used for igniting oil-gas mixture; the flame nozzle is in threaded connection with the precombustion chamber main body, and two spray holes are formed in the bottom of the flame nozzle, wherein the tangential spray holes are located above the radial spray holes.

Preferably, the fuel injector injects gasoline once in the compression stroke of the piston, and the injected fuel amount is about 1 ml; the injection start timing range is 120 DEG CA BTDC to 160 DEG CA BTDC.

Preferably, the flame nozzle is fixed below the prechamber body through an upper thread structure to form a prechamber space; the bottom of the flame nozzle is provided with tangential and radial spray holes.

Preferably, the number of the tangential spray holes is 4, the tangential spray holes are uniformly distributed at the bottom of the flame spray nozzle, the circumferential inclination angle is more than or equal to 40 degrees, the radial inclination angle is more than or equal to 80 degrees, and the diameter of the tangential spray holes is smaller than that of the spray holes of the common precombustion chamber; the flame propagation speed is accelerated, the flame propagation area is enlarged, and the combustion stability is enhanced.

Preferably, the number of the radial spray holes is 3, the radial spray holes are uniformly distributed below the tangential spray holes, the circumferential inclination angle is 0, the radial inclination angle is less than or equal to 40 degrees, and the diameter of the radial inclination angle is smaller than that of the spray holes of the common precombustion chamber; the flame propagation speed is accelerated, the propagation distance of jet flame is increased, and the combustion stagnation period of the mixed gas is shortened.

Preferably, the oil sprayer and the flame nozzle are both provided with grooves which are fixedly connected with the precombustion chamber main body and the cylinder cover through O-shaped sealing rings, so that the air tightness of the structure is ensured.

Compared with the prior art, the technical scheme provided by the utility model has the following advantages that:

two spray holes are designed on the flame nozzle of the precombustion chamber; the tangential jet holes are inclined at a certain angle in the circumferential direction and the radial direction, and flame is sprayed out through the tangential jet holes to generate circumferential speed and is diffused towards the periphery, so that the propagation area of the flame is increased, the combustion stability is enhanced, and the ignition reliability in the main combustion chamber is ensured; the radial spray holes only have an inclination angle in the radial direction, and the aperture is smaller than the diameter of the spray holes of the existing common precombustion chamber, so that the propagation speed of flame is accelerated, and the propagation distance of jet flow flame is increased, thereby promoting the combustion process, shortening the combustion stagnation period of mixed gas, increasing the pressure rise rate, and having positive influence on the improvement of the thermal efficiency of the gasoline engine.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the utility model and together with the description, serve to explain the principles of the utility model.

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

FIG. 1 is a schematic diagram of the overall configuration of a dual row orifice precombustor in accordance with an embodiment of the present invention;

FIG. 2 is an elevational view of a burner tip for a dual row orifice precombustor according to an embodiment of the present invention;

FIG. 3 is a top view of a burner for a dual row orifice precombustor according to an embodiment of the present invention;

reference numerals: 1-precombustion chamber main body, 2-oil injector, 3-O-shaped sealing ring 1, 4-flame nozzle, 5-O-shaped sealing ring 2, 6-cylinder cover and 7-spark plug. 41-flame nozzle screw thread, 42-flame nozzle groove, 43-tangential spray hole and 44-radial spray hole. Alpha-circumferential inclination angle, beta-radial inclination angle.

Detailed Description

For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the following description, it is to be understood that the orientations and positional relationships indicated by "front", "rear", "upper", "lower", "left", "right", "longitudinal", "lateral", "vertical", "horizontal", "top", "bottom", "inner", "outer", "leading", "trailing", and the like are configured and operated in specific orientations based on the orientations and positional relationships shown in the drawings, and are only for convenience of describing the present invention, and do not indicate that the device or element referred to must have a specific orientation, and thus, are not to be construed as limiting the present invention.

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the utility model. It will be apparent, however, to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

In order to implement the double-row jet hole type precombustion chamber, the precombustion chamber of the direct-injection gasoline engine is improved, and the structure of the precombustion chamber is schematically shown in figure 1, and the precombustion chamber comprises a precombustion chamber main body, an oil injector, a spark plug, a flame nozzle and a sealing ring; the fuel injector is arranged on the right side of the precombustion chamber main body and is used for injecting gasoline; the spark plug is arranged on the left side of the precombustion chamber main body and is used for igniting oil-gas mixture; the flame nozzle is in threaded connection with the precombustion chamber main body, and two spray holes are formed in the bottom of the flame nozzle, wherein the tangential spray holes are located above the radial spray holes.

In one embodiment, an O-ring seal 1 is fitted between the injector 2 and the prechamber body to ensure prechamber airtightness.

In one embodiment, the flame nozzle 4 is fixed with the prechamber body through a threaded connection, and forms a prechamber space; an O-shaped sealing ring 2 is assembled between the flame-projecting nozzle 4 and the cylinder cover 6, so that the air tightness in the cylinder is ensured.

In one embodiment, the gasoline injection signal is controlled by the ECU. In the compression stroke of the piston, air enters the precombustion chamber through a spray hole on the flame spray nozzle, the oil sprayer is controlled to spray 1ml of oil at 120-160-degree CA BTDC, and the air are fully mixed to form a relatively concentrated gasoline mixed gas and reduce oil consumption.

In one embodiment, the flame in the precombustion chamber is firstly ejected through the tangential jet holes and generates circumferential speed, the radial inclination angle of the tangential jet holes is larger, the flame spreads to the periphery in the cylinder, the flame spreading area is enlarged, the combustion stability is enhanced, and the ignition reliability in the main combustion chamber is ensured; then (with extremely short interval) the flame is sprayed out from the radial spray holes, and the radial inclination angle of the spray holes is smaller, so that the propagation distance of the flame can be increased; compared with the common jet holes of the precombustion chamber, the two jet holes have the advantages that the diameters are reduced, and the propagation speed of flame is favorably improved. Under the action of the above-mentioned beneficial factors, the utility model promotes the combustion process, shortens the combustion stagnation period of the mixed gas, increases the pressure rise rate and has positive influence on the improvement of the thermal efficiency of the gasoline engine.

It is to be understood that the foregoing examples, while indicating the preferred embodiments of the utility model, are given by way of illustration and description, and are not to be construed as limiting the scope of the utility model; it should be noted that, for those skilled in the art, the above technical features can be freely combined, and several changes and modifications can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention; therefore, all equivalent changes and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.

Claims

1. A double-row jet hole type precombustion chamber is characterized by comprising a precombustion chamber main body, an oil injector, a spark plug, a jet nozzle and a sealing ring; the fuel injector is arranged on the right side of the precombustion chamber main body and is used for injecting gasoline; the spark plug is arranged on the left side of the precombustion chamber main body and is used for igniting oil-gas mixture; the flame nozzle is in threaded connection with the precombustion chamber main body, and two spray holes are formed in the bottom of the flame nozzle, wherein the tangential spray holes are located above the radial spray holes.

2. The dual row orifice precombustor of claim 1 wherein said fuel injector injects about 1ml of fuel once during the compression stroke of the piston; the injection start timing range is 120 DEG CA BTDC to 160 DEG CA BTDC.

3. The dual row orifice prechamber of claim 1, wherein the burner is attached to the prechamber body by an upper threaded structure forming a prechamber space; the bottom of the flame nozzle is provided with tangential and radial spray holes.

4. The dual row orifice precombustor of claim 3 wherein the number of tangential orifices is 4 and are uniformly distributed at the bottom of the burner, the circumferential angle of inclination is greater than or equal to 40 °, the radial angle of inclination is greater than or equal to 80 °, and the diameter is smaller than that of the orifices of the conventional precombustor.

5. The dual row orifice precombustor of claim 3 wherein said radial orifices are 3 and are uniformly distributed below the tangential orifices, the circumferential angle of inclination is 0, the radial angle of inclination is less than or equal to 40 °, and the diameter is less than that of the conventional precombustor orifices.

6. The dual row orifice precombustor of claim 1 wherein the fuel injector and the burner are each recessed and are secured to the precombustor body and the cylinder head by O-rings.