Constant-volume combustion chamber structure
By adopting a circulating diffused air inlet and a guide flow velocity distribution port structure in the constant volume combustion chamber, the problem of slow exhaust gas discharge is solved, achieving rapid exhaust and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2026-03-06
AI Technical Summary
In constant volume combustion, the exhaust gas inside the combustion chamber is discharged slowly, which leads to changes in oxygen content, affecting the accuracy of the measurement results, and the long testing time results in high costs.
It adopts a diffused air inlet and sets multiple sets of guide flow velocity distribution ports at the end of the air inlet channel to control the airflow direction and flow velocity distribution, avoid the generation of eddies, and ensure that the exhaust gas is discharged quickly.
It shortened the testing time, reduced the amount of compressed air used, and lowered the testing cost.
Smart Images
Figure CN223977191U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of combustion chamber technology, specifically to a constant-volume combustion chamber structure. Background Technology
[0002] The constant volume combustion method is an experiment conducted in a combustion chamber with a fixed volume. In the process of deriving the cetane number of diesel fuel using the constant volume combustion method, compressed air at a standard pressure (about 2 MPa) is injected into the constant volume combustion chamber and heated to a fixed value within the test temperature range (560℃~640℃). Then, diesel fuel is injected into the combustion chamber at a set pressure (about 100 MPa) for combustion, thereby measuring the relevant data of the ignition lag period and combustion lag period. After that, the exhaust gas after combustion is discharged, and new compressed air is injected again. The above process is repeated continuously, and the relevant data are measured and averaged to finally obtain the determination result.
[0003] Combustion requires a stable supply of compressed air. Changes in pressure and temperature within the combustion chamber will alter the measured results, and variations in oxygen content will also affect combustion characteristics. While pressure and temperature changes can be monitored and controlled in real-time within the combustion chamber, exhaust gas is directly injected with fresh compressed air through a straight-through inlet. During this process, a penetrating vortex forms between the exhaust gas and compressed air, causing them to merge and resulting in slow exhaust gas discharge. Furthermore, the injected compressed air contains some exhaust gas, leading to changes in oxygen content that cannot be accurately measured internally and must be detected externally. Although prolonged compressed air injection can improve accuracy, the low temperature of the compressed air carries away a significant amount of heat, resulting in substantial temperature variations. This leads to longer control and adjustment cycles during subsequent tests, significantly increasing testing time and wasting a large amount of compressed air, thus increasing testing costs. Utility Model Content
[0004] The purpose of this invention is to provide a constant-volume combustion chamber structure in order to solve the above problems.
[0005] To achieve the above objectives, this utility model specifically adopts the following technical solution, including:
[0006] A combustion chamber body, wherein air inlets and exhaust outlets are provided on both sides of the combustion chamber body;
[0007] The air intake includes an air intake channel and a guide flow velocity distribution port, and the air intake channel is connected to the combustion chamber body through the guide flow velocity distribution port.
[0008] As a further description of the above technical solution, a combustion chamber is provided inside the combustion chamber body, and the air inlet and the exhaust outlet penetrate the inner wall of the combustion chamber and communicate with the combustion chamber.
[0009] As a further description of the above technical solution, a fuel injection port is provided at the top of the combustion chamber, and the fuel injection port is used to inject the diesel fuel to be tested.
[0010] As a further description of the above technical solution, the top of the air intake channel is connected to multiple sets of guide flow velocity distribution ports.
[0011] As a further description of the above technical solution, the diameter of the air intake channel is 20-30% of the diameter of the air intake port.
[0012] As a further description of the above technical solution, the guide flow velocity distribution port is provided in 2-4 sets.
[0013] As a further description of the above technical solution, the axis of each group of guide flow velocity distribution ports intersects with the axis of the air intake channel.
[0014] As a further description of the above technical solution, the diameter of each group of guide flow velocity distribution ports is different.
[0015] As a further description of the above technical solution, the diameter of the guide flow velocity distribution port is 10-40% of the diameter of the air intake channel.
[0016] As a further description of the above technical solution, the diameter of the guide flow velocity distribution port gradually decreases along the curve at the end of the air inlet.
[0017] The beneficial effects of this utility model are as follows:
[0018] This invention replaces the straight-through air inlet with a diffused air inlet. Based on the directional relationship between the air inlet and the exhaust port, multiple sets of guide velocity distribution ports are opened at the end of the air inlet channel. The diffusion velocity ratio in different directions is adjusted to control the guidance and velocity distribution of the air inlet. This allows compressed air to be injected smoothly and evenly, enabling exhaust gas to be discharged quickly from the exhaust port. It prevents the formation of penetrating eddies inside the combustion chamber, and combustion residues do not clog the guide velocity distribution ports. This effectively shortens the testing time, reduces the amount of compressed air used, and lowers the testing cost.
[0019] To more clearly illustrate the structural features and functions of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the constant-volume combustion chamber structure of this utility model;
[0021] Figure 2 yes Figure 1 A schematic diagram of the structure of the central air intake.
[0022] Figure label:
[0023] 1. Combustion chamber body; 11. Air inlet; 111. Air intake passage; 112. Guide flow velocity distribution port; 12. Exhaust port; 13. Combustion chamber; 14. Fuel injection port. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.
[0025] like Figures 1-2 As shown, in one embodiment, a constant-volume combustion chamber structure includes: a combustion chamber body 1, wherein a combustion chamber 13 is provided inside the combustion chamber body 1, which is responsible for containing the diesel fuel to be tested and providing space for its combustion; and an injection port 14 is provided on the top of the combustion chamber for injecting the diesel fuel to be tested.
[0026] Furthermore, an air inlet 11 and an exhaust outlet 12 are provided on both sides of the combustion chamber body 1. The air inlet 11 and the exhaust outlet 12 penetrate the inner wall of the combustion chamber and are connected to the combustion chamber 13. After the test is completed, the air inlet 11 is responsible for introducing compressed air, while the exhaust outlet 12 is used to discharge the exhaust gas after combustion.
[0027] Please continue reading. Figures 1-2 In this embodiment, the air intake 11 includes an air intake channel 111 and multiple sets of guide flow velocity distribution ports 112. The top of the air intake channel 111 is connected to the combustion chamber body 1 via the multiple sets of guide flow velocity distribution ports 112, thereby guiding compressed air from the air intake channel 111 into the combustion chamber 13 through the guide flow velocity distribution ports 112. Specifically, the diameter of the air intake channel 111 is 20-30% of the diameter of the air intake 11.
[0028] Furthermore, 2-4 sets of guide flow velocity distribution ports 112 are provided, and the axis of each set of guide flow velocity distribution ports 112 intersects the axis of the intake channel 111. The diameter of each set of guide flow velocity distribution ports 112 is different. Specifically, the diameter of the guide flow velocity distribution port 112 is 10-40% of the diameter of the intake channel 111, and the diameter of the guide flow velocity distribution port 112 gradually decreases along the curve at the end of the intake port 11. The flow velocity and direction of compressed air can be precisely controlled according to the directional relationship between the intake port 11 and the exhaust port 12, ensuring that the airflow can be diffusely distributed in multiple directions. This prevents the generation of penetrating vortices when compressed air is injected, and allows the exhaust gas to be smoothly squeezed out, effectively shortening the exhaust gas discharge time, reducing the amount of compressed air used, and lowering the testing cost.
[0029] Working principle: The straight-through air inlet 11 is replaced with a diffused air inlet 11. Based on the directional relationship between the air inlet 11 and the exhaust port 12, multiple sets of guide flow velocity distribution ports 112 are opened at the end of the air intake channel 111. The diffusion speed of the airflow in different directions can be adjusted, thereby precisely controlling the guidance and flow velocity distribution of the airflow. This allows the compressed air to be injected smoothly and gradually, generating only a small range of vortices on the end face of the guide flow velocity distribution port 112, without generating penetrating vortices inside the combustion chamber 13. This allows the exhaust gas to be quickly discharged from the exhaust port 12, and the combustion residue will not block the guide flow velocity distribution port 112.
[0030] Subsequently, a comparative test was conducted using the combustion chamber in the "High-Altitude Refined Oil Quality and Safety Laboratory". After the test, the test time and compressed air consumption were statistically analyzed. Through the above technical solution, this application can shorten the test time and compressed air consumption by more than 50%, thus effectively reducing the test time and lowering the test cost.
[0031] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A constant volume combustion chamber structure, characterized by, Comprising: a combustion chamber body (1) provided with an air inlet (11) and an exhaust port (12) on both sides; the air inlet (11) comprises an air inlet channel (111) and a guide flow rate distribution port (112), the air inlet channel (111) is communicated with the guide flow rate distribution port (112) and the combustion chamber body (1).
2. The constant volume combustion chamber structure according to claim 1, characterized by, the combustion chamber body (1) is internally provided with a combustion cavity (13), the air inlet (11) and the exhaust port (12) are communicated through the combustion chamber inner wall and the combustion cavity (13).
3. The constant volume combustion chamber structure according to claim 2, characterized by, the top of the combustion chamber is provided with an oil injection port (14) for injecting diesel to be tested.
4. The constant volume combustion chamber structure according to claim 1, characterized by, the top of the air inlet channel (111) is communicated with a plurality of guide flow rate distribution ports (112).
5. The constant volume combustion chamber structure according to claim 4, characterized by the diameter of the air inlet channel (111) is 20-30% of the diameter of the air inlet (11).
6. The constant volume combustion chamber structure according to claim 1, characterized by the guide flow rate distribution port (112) is provided with 2-4 groups.
7. The constant volume combustion chamber structure according to claim 6, characterized by the axis of each group of the guide flow rate distribution port (112) intersects with the axis of the air inlet channel (111).
8. The constant volume combustion chamber structure according to claim 6, characterized by, the diameters of each group of the guide flow rate distribution port (112) are different.
9. The constant volume combustion chamber structure according to claim 6, characterized by the diameter of the guide flow rate distribution port (112) is 10-40% of the diameter of the air inlet channel (111).
10. The constant volume combustion chamber structure according to claim 6, characterized by, the diameter of the guide flow rate distribution port (112) gradually decreases along the curve of the end of the air inlet (11).