CN215633303U

CN215633303U - Guide plate type natural gas engine combustion chamber structure

Info

Publication number: CN215633303U
Application number: CN202120921191.0U
Authority: CN
Inventors: 曾丽丽; 李军成; 朱赞
Original assignee: Guangxi Yuchai Machinery Co Ltd
Current assignee: Guangxi Yuchai Machinery Co Ltd
Priority date: 2021-04-29
Filing date: 2021-04-29
Publication date: 2022-01-25
Anticipated expiration: 2031-04-29

Abstract

The embodiment of the application discloses a guide plate type natural gas engine combustion chamber structure for increasing turbulent kinetic energy above a combustion chamber pit, shortening a stagnation period and a combustion duration during combustion and widening a detonation boundary. The method in the embodiment of the application comprises the following steps: the combustion chamber comprises a guide plate structure, a combustion chamber pit, a piston body and an air inlet channel; the guide plate structure and the combustion chamber pit are formed on the top surface of the piston body; the air inlet channel is arranged above the combustion chamber pit, and the combustion chamber pit is used for forming a vortex of ordered movement by airflow; and in the process of extruding the combustion chamber pit, the flow guide plate structure is used for pushing the gas mixed airflow to the top surface of the combustion chamber pit.

Description

Guide plate type natural gas engine combustion chamber structure

Technical Field

The embodiment of the application relates to the technical field of natural gas engine combustion chambers, in particular to a guide plate type natural gas engine combustion chamber structure.

Background

The natural gas engine combustion chamber structure has obvious influence on the turbulence intensity in the cylinder, for example, the influence on the turbulence intensity in the cylinder can be enhanced by optimizing the shape of the combustion chamber, expanding the coverage area of a high-turbulence-energy area and the like. At present, most natural gas engines are developed by improving diesel engines, the natural gas engines use volute air passages of the original diesel engines, and the performance of the air passages is mainly vortex and assisted by tumble.

Most of existing natural gas engine combustion chambers are straight-tube type, after a piston is matched with a spiral air inlet, airflow can form large-scale vortex which moves orderly in a pit of the combustion chamber, then the rotation direction of the vortex is determined according to the position of the air passage, when the combustion chamber is at the final stage of compression, the large-scale vortex in the pit of the combustion chamber is broken into small-scale vortex masses under the action of squeezing flow, and the small-scale vortex masses cannot be pushed to the upper part of the pit of the combustion chamber due to the fact that the inner wall surface of the combustion chamber is not provided with a guide structure, namely the small-scale vortex masses are close to a spark plug, so that the turbulent kinetic energy near the spark plug is lower than that in the pit of the combustion chamber, the stagnation period in the combustion chamber is increased, the propagation speed of flame is slowed, the spontaneous combustion probability of far-end mixed gas is increased, and the detonation boundary is narrowed.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a guide plate type natural gas engine combustion chamber structure for increasing turbulent kinetic energy above a combustion chamber pit, shortening a combustion lag phase and a combustion duration during combustion and widening a detonation boundary.

The application provides a deflector formula natural gas engine combustion chamber structure for:

the combustion chamber comprises a guide plate structure, a combustion chamber pit, a piston body and an air inlet channel;

the guide plate structure and the combustion chamber pit are formed on the top surface of the piston body;

the air inlet channel is arranged above the combustion chamber pit, and the combustion chamber pit is used for forming a vortex of ordered movement by airflow;

and in the process of extruding the combustion chamber pit, the flow guide plate structure is used for pushing the gas mixed airflow to the top surface of the combustion chamber pit.

Optionally, the baffle structure includes:

a flow-facing surface, an inclined surface and a backflow surface;

the incident flow surface is vertically arranged on the plane of the inner wall surface of the combustion chamber pit;

the inclined surface is connected with the incident flow surface;

the backflow surface is connected with the inclined surface and used for reducing an airflow backflow area.

Optionally, the outer surface of the backflow surface is a circular arc surface.

Optionally, the arc radius range of the arc surface is set to be 6 to 10 mm.

Optionally, the radius of the circular arc is larger than the radius of other circular arcs in the baffle structure.

Optionally, the angle range of the included angle between the incident flow surface and the vertical direction of the central line connecting lines of the outlets at the two ends of the air inlet channel is set to be 45-90 degrees.

Optionally, a ratio of a horizontal distance between the inclined surface and a side wall surface of the combustion chamber pit to a horizontal distance between a side wall surface of the combustion chamber pit and a center line of the combustion chamber pit ranges from 0.5 to 0.65.

Optionally, the included angle between the inclined surface and the bottom of the combustion chamber pit is set to be 45-60 degrees.

Optionally, the inclined surface and the circumferential direction span angle range using the midpoint of the combustion chamber pit as the center are 45 to 180 degrees.

Optionally, a joint of the combustion chamber pit and the inclined surface is rounded.

According to the technical scheme, the embodiment of the application has the following advantages:

this application is through providing a water conservancy diversion plate-type natural gas engine combustion chamber structure that has guide plate structure, combustion chamber pit, piston body and intake duct, guide plate structure and combustion chamber pit have formed the piston top surface of piston body, and combustion chamber pit top is located to the intake duct, and this combustion chamber structure can increase the turbulent kinetic energy of combustion chamber pit top, and the stagnation period and the combustion duration when making the burning shorten, widen the detonation boundary. The combustion chamber pit is used for forming orderly moving vortex by airflow, and the guide plate structure is used for pushing the gas mixed airflow to the top surface of the combustion chamber pit in the flow extruding process of the combustion chamber pit.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of a combustion chamber structure of a guide plate type natural gas engine in an embodiment of the application;

fig. 2 is a schematic structural diagram of another embodiment of a baffle type natural gas engine combustion chamber structure in the embodiment of the application.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of the present invention.

Referring to fig. 1 to 2, in an embodiment of the present application, a baffle type natural gas engine combustion chamber structure is provided, including: the combustion chamber comprises a guide plate structure 1, a combustion chamber pit 2, a piston body and an air inlet channel, wherein the guide plate structure 1 and the combustion chamber pit 2 are formed on the top surface of a piston of the piston body; the air inlet channel is arranged above the combustion chamber pit 2, and the combustion chamber pit 2 is used for forming a vortex of ordered movement by airflow; the deflector structure 1 is used for pushing the gas mixture flow to the top surface of the combustion chamber pit 2 in the process of extruding the combustion chamber pit 2.

In the embodiment of the application, a guide plate type natural gas engine combustion chamber structure is provided, and the guide plate type natural gas engine combustion chamber structure is provided with a guide plate structure 1, a combustion chamber pit 2, a piston body and an air inlet channel, and is used for increasing turbulent kinetic energy above the combustion chamber pit, so that a combustion lag period and a combustion duration during combustion are shortened, and a detonation boundary is widened.

In the application, a baffle structure 1 is designed in a combustion chamber pit 2, the baffle structure 1 comprises an incident flow surface 21, an inclined surface 22 and a backflow surface 23, wherein the incident flow surface 21 is vertically arranged on the plane of the inner wall surface of the combustion chamber pit 2, the inclined surface 22 is connected with the incident flow surface 21, the backflow surface 23 is connected with the inclined surface 22, and the backflow surface 23 is used for reducing the airflow backflow area. It should be noted that, since a recirculation region of the airflow is formed near the recirculation surface 23, the outer surface of the recirculation surface 23 needs to be designed as a circular arc surface, the radius of the circular arc surface is set to be 6 to 10mm, the circular arc radius of the circular arc surface here is larger than other circular arc radii in the baffle structure 1, and the other circular arc radii are generally 2 to 3 mm. The outer surface of the return surface 23 may be designed to have a structure in which a circular arc surface and a plane are combined with each other, in addition to a full circular arc surface.

Since the air inlet channel branches off two air channels as air flow outlets in the combustion chamber structure, the central point of the combustion chamber pit 2 can be used as a reference point, and the near-far-end outlets of the air channels can be determined according to the distance of each air channel from the reference point, for example, the outlet at the end farther from the central point can be called a far-end outlet 24, and the outlet at the end closer to the central point can be called a near-end outlet 25.

Optionally, an included angle range of the perpendicular direction between the incident flow surface 21 and a central line connecting the outlets at the two ends of the air inlet channel is set to be 45 to 90 degrees, and the included angle a1 is shown in fig. 1. Preferably, the position of the incident flow surface 21 may be arranged directly below the distal outlet 24 of the air intake duct. The inclined surface 22 has an angle range of 45 to 180 degrees with respect to the circumferential span centered on the midpoint of the combustion bowl 2, and the span has an angle a2 as shown in fig. 1.

Referring to fig. 2, in order to make the connection between the planes smoother, the ratio of the horizontal distance L1 between the inclined surface 22 and the inner wall surface of the combustion pocket 2 to the horizontal distance L2 between the inner wall surface of the combustion pocket 2 and the center line of the combustion pocket 2 may be set to 0.5 to 0.65, and preferably, the ratio may be controlled to 0.55. The angle a3 between the inclined surface 22 and the bottom of the combustion chamber recess 2 is set to 45 to 60 degrees, preferably 55 degrees, and the junction between the combustion chamber recess 2 and the inclined surface 22 is rounded. Further, the connection of the inclined surface 22 to the inner wall surface and the bottom of the combustion chamber may be made by a fillet, and the fillet radius may not generally exceed 3 mm.

It is to be noted in particular that the guide plate structure 1 mentioned in this application is at least 1. When the number of the guide plate structures 1 is greater than 1, the total length of the guide plate structures 1 may not be equal, and the distance between the guide plate structures 1 may not be equal, preferably, the total length of the guide plate structures 1 remains equal, the distance between the guide plate structures 1 is equal, and the specific length and distance are not limited here.

In the embodiment of the application, when the mixture of the fuel gas enters the combustion chamber pit 2 from the far-end outlet and the near-end outlet of the air inlet channel, the air flow in the combustion chamber pit 2 moves along the inner wall surface, and the orderliness of vortex motion is broken. The gas mixture enters the combustion chamber pit 2 from the far-end outlet 24 and the near-end outlet 25 of the inlet duct, and the gas flow in the pit determines the corresponding movement direction according to the position of the inlet duct and carries out vortex movement along the direction.

In the running process of the guide plate type natural gas engine combustion chamber, a piston body in the engine combustion chamber moves upwards, moving air flow can impact the incident flow surface 21, so that the moving direction of the air flow is changed, gas mixture enters the combustion chamber pit 2 under the action of flow extrusion, and the air flow is pushed to the upper part of the combustion chamber pit 2 and is close to the vicinity of a spark plug under the guide action of the inclined surface 22, so that the turbulent kinetic energy of the combustion chamber pit 2 is increased. It is particularly noted that, in the process of changing the moving direction of the airflow, the order of the vortex movement is broken, so that after the airflow hits the wall, the large-scale vortex is broken into small-scale vortex masses, and after the moving direction of the airflow is changed, the high-turbulence-energy region can be pushed to the upper part of the combustion chamber pit 2, namely to the vicinity of the spark plug, thereby shortening the combustion lag phase and the combustion duration, reducing the spontaneous combustion probability of the far-end mixer, and widening the detonation boundary.

If the aforementioned direction of rotation of the vortex direction changes, the incident flow surface 21 and the return flow surface 23 are also displaced.

Claims

1. The utility model provides a deflector formula natural gas engine combustion chamber structure which characterized in that includes:

2. The combustor structure of claim 1, wherein the baffle structure comprises:

a flow-facing surface, an inclined surface and a backflow surface;

the inclined surface is connected with the incident flow surface;

3. The combustion chamber structure according to claim 2, wherein an outer surface of the return surface is provided as a circular arc surface.

4. The combustion chamber structure according to claim 3, wherein a circular arc radius of the circular arc surface is set to 6 to 10 mm.

5. The combustor structure of claim 4, wherein the radius of the arc is larger than other radii of the arc in the baffle structure.

6. The combustion chamber structure of claim 5, wherein the angle range of the included angle between the incident flow surface and the perpendicular direction of the connecting line of the central lines of the outlets at the two ends of the air inlet channel is set to be 45-90 degrees.

7. The combustion chamber structure of claim 6, wherein a ratio of a horizontal distance between the inclined surface and the side wall surface of the combustion chamber pit to a horizontal distance between the side wall surface of the combustion chamber pit and the center line of the combustion chamber pit ranges from 0.5 to 0.65.

8. The combustion chamber structure of claim 7, wherein the inclined surface is provided at an angle ranging from 45 to 60 degrees with respect to the bottom of the combustion chamber pit.

9. The combustion chamber structure according to claim 8, wherein the inclined surface has an angular range of 45 to 180 degrees with respect to a circumferential direction around a midpoint of the combustion chamber pit.

10. The combustion chamber structure as claimed in any one of claims 2 to 9, wherein a junction of the combustion chamber recess and the inclined surface is rounded.