a fuel injector

Abstract

A fuel injector, comprising a needle valve and a valve seat, the needle valve includes a needle valve head and a needle valve tail, the needle valve tail is a cavity structure; the surface of the needle valve head and the inner ring surface of the valve seat A cylindrical tubular body is formed between them, and the cylindrical tubular body and the cavity at the tail of the needle valve form a tapering and diverging flow channel of the fuel injector. A fuel injector described in this application can increase the fuel injection velocity at the nozzle hole of the fuel injector and improve the fuel atomization characteristics after the outlet of the nozzle hole without adding external conditions such as increasing injection pressure or adding other components , The aerodynamic effect of the supersonic airflow can also increase the vortex at the outlet of the nozzle, making the spray converge towards the axis, further refining the spray particle size and improving the spray characteristics.

Description

technical field [0001] The present application relates to the field of in-cylinder fuel injection systems of aero-engines, in particular to a fuel injector. Background technique [0002] A fuel injector is a device that premixes a certain amount of fuel at a certain pressure with compressed air and injects them into the cylinder of an aeroengine. Aeroengines mainly use kerosene as the fuel medium. But kerosene is less evaporative, and there is not enough time for the fuel to evaporate before the spark plug ignites during the piston engine's working cycle. In order to make the mixed fuel ignite and burn better, it is required to refine the particle size of the fuel as much as possible to shorten the evaporation time of the fuel. [0003] At present, in order to make the fuel burn more fully, the following measures are usually adopted: 1) high-pressure injection is used; 2) the diameter of the nozzle hole is reduced; 3) an atomizer is set. [0004] In order to obtain a good...

AI Technical Summary

Problems solved by technology

[0007] Setting the atomizer increases the number of parts of the air-assisted atomizing injector, increases the processing cost, and increases the difficulty of assembly

In addition, multiple disks are stacked in the sleeve, which adds a lot of uncertain factors to the flow of the mixture of air and fuel. The circumferential arrangement and mutual position of each disk will have a great impact on the flow of the entire fuel mixture.

Multiple disks are stacked in the sleeve, so that residual fuel is extremely easy to accumulate in the edge gap of the disk with a certain shape, which is easy to cause the nozzle hole to be blocked and carbon deposits, which is not conducive to the formation of a good spray

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