Afterburner structure based on self-excitation sweeping oscillation fuel nozzle

Abstract

The invention provides an afterburner structure based on a self-excitation sweeping oscillation fuel nozzle. According to the fuel nozzle, under the condition of stable inlet fuel flow, the coanda effect of the fluid and the alternating feedback effect of the feedback channel, sweeping type oscillating jet flow with a certain frequency is formed at an outlet, so that the space uniformity of fuel injection is improved, on the basis that the structural complexity of an afterburner of an existing turbine engine and a ramjet combustion chamber of a subsonic combustion ramjet engine is not increased, the atomization performance and the oil-gas mixing uniformity of fuel oil in the afterburner / ramjet combustion chamber can be greatly improved, the combustion efficiency and the combustion instability of the engine are improved, meanwhile, the lengths of the afterburner and the subsonic combustion ramjet combustion chamber are shortened.

Description

technical field [0001] The invention belongs to the technical field of fuel injection and structural design of aero-engines, and in particular relates to fuel injection and structural forms in afterburning chambers. Background technique [0002] Certain aeroengines may not perform well across the entire thrust range. For example, when an aircraft takes off, it needs a lot more thrust than when it is cruising. If the engine is designed according to the take-off thrust, the mass of the engine will be too large, and the engine will be in a non-design point state during cruising, and the performance will be very poor; If the engine is not designed for thrust, it will cause the aircraft to fail to take off normally. One of the measures to solve the above problems is to add an afterburner between the gas turbine and the nozzle of the engine to greatly increase the engine thrust in a short time. Although the mass of the afterburner is only about 1 / 5 of the engine, the thrust can ...

AI Technical Summary

Problems solved by technology

However, if the traditional direct injection fuel nozzle is still used in the afterburner and the sub-combustion ram combustor, although its structure is simple, the spatial distribution of the injected fuel is extremely uneven, which will seriously affect the combustion efficiency; at the same time As a result, the flow distance for atomization and mixing in the high-speed transverse airflow is too long, which makes it difficult to further reduce the length of the afterburner for the next-generation engine; at the same time, the inlet temperature of the next-generation afterburner is higher, and the spontaneous combustion is delayed. The time is shorter, and the good atomization, evaporation and mixing of fuel must be completed within 50mm to avoid spontaneous combustion of fuel. It is difficult to achieve the above design goals with ordinary direct injection fuel nozzles

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