CN114719292A

CN114719292A - Fuel convection atomization scheme for miniature combustion chamber

Info

Publication number: CN114719292A
Application number: CN202210250451.5A
Authority: CN
Inventors: 张群; 杨卓蒙; 夏怡真; 吴智迪; 范颖静; 周子豪
Original assignee: Northwestern Polytechnical University
Current assignee: Northwestern Polytechnical University
Priority date: 2022-03-15
Filing date: 2022-03-15
Publication date: 2022-07-08

Abstract

The invention provides a fuel convection atomization scheme for a micro combustion chamber, and relates to the technical field of micro engine combustion chambers. The invention improves the evaporating pipe and the oil supply structure in the micro combustion chamber. The tail end of the oil supply pipe is processed into a porous structure, fuel enters the evaporation pipe through the vertical small hole, the fuel vertically enters the evaporation pipe and interacts with the airflow inside the evaporation pipe, fuel atomization and air mixing can be effectively achieved, meanwhile, the spiral rib plate structure is arranged in the evaporation pipe, the turbulence intensity of the airflow inside the evaporation pipe is enhanced, oil and gas mixing is facilitated, the atomization and mixing effect of the fuel can be effectively improved, and the combustion performance of the micro combustion chamber can be effectively improved.

Description

Fuel convection atomization scheme for miniature combustion chamber

Technical Field

The invention belongs to the technical field of micro combustion chambers, and particularly relates to a fuel convection atomization scheme of a micro combustion chamber.

Background

The micro engine has the characteristics of relatively simple structure, low cost and short research and development period, simultaneously covers the core technology of each aspect of the gas turbine, and is very favorable for serving as a scientific research, teaching and industrial platform. The micro engine is used as a verification platform for various new technologies from the beginning, so that the research and development experience of the aero-engine can be rapidly accumulated, and the research and development capability can be established. And many core technologies of the micro aeroengine and the micro gas turbine are the same, and after the micro aeroengine is successfully researched and developed, the micro aeroengine can be quickly transplanted to the ground for application, so that compared with a large engine, the micro aeroengine has the advantages of more flexible use scene, stronger universality and wider market range.

The combustion chamber is one of the core components of the engine. The combustion chamber of a micro engine cannot be scaled according to the size of the engine in consideration of other factors such as combustion efficiency in the combustion chamber, so that the smaller the size of the engine is, the larger the proportion of the overall space occupied by the combustion chamber is. Compared with the conventional combustion chamber, the micro combustion chamber has the main characteristics that: the combustion chamber has small volume, short combustion time of liquid fuel oil, low combustion efficiency, large flow loss and poor combustion stability; the space layout is limited, an evaporating pipe with low-pressure oil supply and a direct flow flame stabilizing structure are generally adopted, the atomization quality is generally inferior to that of a more advanced air atomization nozzle, and the generated incomplete combustion loss is large. Therefore, the core problem of the micro combustor is how to improve various performances of the combustor under the condition of limited space, mainly including improving combustion efficiency, reducing total pressure loss and improving combustion stability. Or conversely, the size of the combustion chamber space is reduced as much as possible on the premise of ensuring the performance.

According to the invention, through improving the structure of the evaporation pipe and the oil pipe in the combustion chamber of the micro-turbojet engine, the defects caused by design can be compensated to a certain extent, the combustion performance of the micro-combustion chamber is improved, and the micro-turbojet engine can also be designed into the structure of a common micro-turbojet engine.

Disclosure of Invention

The invention aims to solve the technical problem of providing a fuel convection atomization scheme of a miniature combustion chamber. Compared with the prior art, the fuel atomizing device has the advantages that the tail end of the fuel pipe is in a porous net-shaped layout, so that fuel vertically enters the evaporation pipe from the fuel pipe, the flow direction of the fuel is perpendicular to the airflow direction, and the fuel atomizing effect can be improved by effectively utilizing the shearing action of the airflow. Meanwhile, the inside of the evaporation pipe adopts a spiral rib plate structure, so that the turbulence intensity of airflow is enhanced, oil and gas are better mixed, and the combustion performance of the micro combustion chamber is improved.

Technical scheme

The invention aims to provide a fuel convection atomization scheme of a micro combustion chamber, which can effectively improve the fuel atomization effect and the oil-gas mixing effect and realize the optimization of the combustion characteristic of the micro combustion chamber.

The technical scheme of the invention is as follows:

the utility model provides a miniature combustion chamber fuel convection atomization scheme, includes flame tube, evaporating pipe, oil pipe, its characterized in that: based on the structure and the function of the combustion chamber of the common micro turbojet engine, the fuel oil flow channel in the combustion chamber is designed to be vertical to the air flow channel, so that the fuel oil atomization effect is effectively improved; the inner part of the evaporation pipe is designed into the spiral rib plate, so that the turbulence intensity of airflow is enhanced, and the oil-gas mixing effect is improved.

The combustor oil pipe is characterized in that: based on the oil pipe of a common micro combustion chamber, the direct current structure at the tail end of the oil pipe is designed into a closed porous net structure, so that fuel oil vertically enters the evaporation pipe from the oil pipe, and the atomization effect of the fuel oil is improved. 9 groups of 36 small holes are uniformly distributed at the tail end of the oil pipe in the circumferential direction, and the emergent holes form an angle of 90 degrees with the airflow direction in the evaporation pipe.

The combustion chamber evaporating pipe is characterized in that: the inside spiral rib plate structure that adopts of design evaporating pipe strengthens the inside air current torrent characteristic of evaporating pipe, and four group spiral rib plate structures of evaporating pipe circumference distribution, every group are rotatory 90, and the spiral is two weeks.

The invention has the following beneficial effects:

compared with the traditional micro combustion chamber evaporation tube atomization structure, the micro combustion chamber fuel convection atomization scheme is more optimized. The porous design at the tail end of the oil pipe can ensure that fuel oil enters the evaporation pipe in a vertical incidence mode, the shearing action of airflow is fully utilized, and the atomization effect of the fuel oil is improved. The spiral rib plate structure in the evaporating pipe can greatly enhance the turbulence characteristic of airflow, improve the shearing action of the airflow and enable the airflow and fuel oil to be mixed well. The improvement of the two characteristics can directly optimize the combustion performance of the micro combustion chamber.

Drawings

FIG. 1: local semi-section view of miniature combustion chamber fuel convection atomization scheme

FIG. 2: miniature combustion chamber fuel convection atomization scheme 3/4 cross-sectional view

FIG. 3: air inlet cross section schematic diagram of fuel convection atomization scheme of micro combustion chamber

FIG. 4: overall schematic diagram of fuel convection atomization scheme of miniature combustion chamber

In the figure: 1-flame tube casing, 2-air flow path, 3-fuel flow path, 4-fuel outlet

Detailed Description

The invention will now be further described with reference to the accompanying drawings in which:

with reference to fig. 1, 2, 3 and 4, the invention relates to a fuel convection atomization scheme of a micro combustion chamber. Fig. 1 is a partial half sectional view of a micro combustion chamber fuel convective atomization scheme, fig. 2 is a sectional view of a micro combustion chamber fuel convective atomization scheme 3/4, fig. 3 is an air intake sectional view of a micro combustion chamber fuel convective atomization scheme, and fig. 4 is an overall schematic view of a micro combustion chamber fuel convective atomization scheme.

Claims

1. The utility model provides a miniature combustion chamber fuel convection atomization scheme, includes flame tube, evaporating pipe, oil pipe, its characterized in that: based on the internal structure and the function of the combustion chamber of the common micro turbojet engine, the combustion chamber evaporation tube and the oil tube are rearranged, the tail end of the oil tube is designed into a multi-pore structure, and the fuel oil is effectively controlled to vertically enter the evaporation tube; the inner part of the evaporation pipe is designed into a spiral rib plate structure, the spiral rib plate structure interacts with fuel oil, the atomization effect is improved, and the section of an outlet is arranged into an inclined plane to form a single expansion pipeline structure.

2. The convective atomization scheme of the micro-combustor fuel of claim 1, characterized in that: the tail end of a fuel oil pipe inside the micro combustion chamber is designed to be of a porous structure, the outlet of the fuel oil pipe and the flowing direction form 90 degrees, fuel oil can vertically enter the evaporation pipe, the evaporation pipe is internally provided with a spiral rib plate structure, the evaporation pipe is integrated with the wall surface of a flame tube of the combustion chamber, air and the fuel oil interact, the atomization effect is improved, and the combustion characteristic of the combustion chamber is improved.

3. A micro combustor fuel convection atomization scheme as set forth in claim 1 and claim 2, wherein: the outlet of the fuel oil pipe and the airflow in the evaporation pipe form 90 degrees, fuel vertically enters the evaporation pipe from the porous structure on the wall surface of the oil pipe, the airflow in the evaporation pipe is disturbed by the spiral rib plates and is subjected to shearing action with the vertical jet flow oil way, the atomization effect is improved, the fuel oil is fully mixed with air, 9 groups of small holes with 36 degrees are uniformly arranged in the axial direction at the tail end of the whole fuel oil pipe, four groups of spiral rib plate structures are distributed in the circumferential direction of the evaporation pipe, each group rotates for 90 degrees and spirals for two weeks.