Flame stabilizer, radial flame stabilizer and combustion chamber

Abstract

The invention discloses a flame stabilizer, a radial flame stabilizer and a combustion chamber. According to the flame stablizer, a stabilizer body comprises a periodic fluctuation profile, wherein the periodic fluctuation profile comprises a plurality of fluctuation units distributed in the radial direction; each fluctuation unit fluctuates in the direction away from the stabilizer body; the fluctuation directions of the adjacent fluctuation units are opposite; and the fluctuation height of each fluctuation unit is gradually increased in the direction from the front end to the rear end. The flame stablizer integrates the functions of mixing, oil supply and flame stabilization; the fuel oil retention time can be prolonged; the fuel oil atomization and evaporation properties can be improved; the mixing of fuel oil and air can be enhanced; the circumferential cross-flame capacity can be improved; the more sufficient combustion in the combustion chamber can be achieved; the working efficiency of the combustion chamber can be improved; the outlet temperature can be more uniform; and the stable working range of an afterburner can be expanded.

Description

technical field [0001] The invention belongs to the technical field of turbo / ramjet combined engine and turbofan engine afterburner / ramjet combustion chamber, and in particular relates to a flame stabilizer, a radial flame stabilizer and a combustion chamber. Background technique [0002] Turbine-based combined cycle (TBCC) as an air-breathing engine has the advantages of wide flight range, conventional take-off and landing, and reusability, and is considered to be the most promising hypersonic vehicle at this stage. powerplant. Due to the large variation of the bypass ratio in the whole working range, the temperature of the incoming flow inside the multi-mode combustion chamber of the TBCC engine is low and the local flow velocity is too high. Under such flow conditions, how to achieve stable ignition and cross-flame, and reduce the flow resistance loss in the non-afterburner state is the goal of the afterburner development at present and in the future. [0003] The flame...

AI Technical Summary

Problems solved by technology

Therefore, it is difficult for the flame behind the radial stabilizer to expand in the circumferential direction, resulting in difficulty in the circumferential cross-flame between adjacent stabilizers; (2) under high temperature flow, the fuel is easily evaporated after being sprayed from the nozzle hole, and on the one hand, it is prone to thermal spontaneous combustion; On the other hand, small oil droplets and gas-phase fuel follow well with the airflow, and their circumferential penetration is weak, so the fuel is mainly concentrated near the downstream of the nozzle position; while under high-speed flow, the penetration depth of fuel is small, and the oil mist is also unable to Diffusion along the circumferential direction is not conducive to the uniform and reasonable distribution of fuel oil on the entire flow section, which reduces the combustion efficiency; (3) When using conventional radial flame stabilizers, in order to improve the ability of circumferential flame joints, the distance between the stabilizers must be shortened

On the premise of not changing the slot width of the stabilizer, it is necessary to increase the number of stabilizers, increase the blockage ratio, and increase the resistance loss; while keeping the blockage ratio unchanged, the slot width of the stabilizer must be reduced, which reduces the stability The flame stability performance of the device

[0006] The conventional design method of oil supply, blending and stabilization in space segmented to perform their respective duties is prone to thermal spontaneous combustion and ablation of the stabilizer in the high-temperature airflow of the advanced afterburner; while in the low-temperature high-speed airflow of the ram combustor Medium, the fuel is not easy to evaporate and ignite, and it is difficult to burn stably

Most modern afterburners and ramcombustors use stabilizers with an integrated design of oil supply and stability. The stabilizers with integrated designs have the following problems in application: (1) When using stabilizers with integrated designs of oil supply and stability , the penetration depth of fuel oil changes with the change of incoming flow velocity, temperature and fuel supply pressure, and the fuel oil is distributed unevenly along the circumference, and local rich and local fuel shortages appear, which affects the spread of flame; (2) multi-mode combustion chamber The radial flame stabilizer in the work in a high-temperature and high-speed gas flow with extremely uneven temperature field, the temperature distribution of the integrated stabilizer is very uneven, and the resulting thermal stress may cause thermal fatigue damage of the stabilizer; ( 3) The fuel distribution of the same root stabilizer is based on the principle of partial pressure fuel supply. The flow rate at the inner ring position is small, and the matching fuel flow rate is correspondingly reduced. If the distance between fuel injection points is guaranteed, the fuel supply oil pressure must be reduced, which is not conducive to fuel atomization ; If the fuel supply oil pressure is guaranteed, the distance between the fuel injection points needs to be increased, which is not conducive to the radial flame transfer of the same root stabilizer; (4) Under the large working condition of the afterburner / ramming combustion chamber, the integrated flame It has been working in the gas flow with extremely uneven temperature field. When the engine is frequently started, stopped and working conditions are changed, the temperature of the gas changes sharply

In the stamping mode, the flow rate is larger and the speed is higher, and the heat release after combustion increases, which increases the thermal burden on the fuel nozzle and flame stabilizer, and is also prone to ablation

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