Jet engine

Abstract

The invention provides a jet engine, which is mainly characterized by consisting of an air inlet (1), a gas compressor (2), a combustion chamber (3), a tail nozzle (5) and an independent power plant (7), wherein a power output shaft (8) of the independent power plant (7) is connected with the compressor (2) and drives the gas compressor (2) to rotate to work. By adopting the independent power plant capable of independently changing the output power to replace a turbine in the prior art, the jet engine effectively reduces the pressure ratio of the gas compressor under the condition of same thrust, and avoids the problem of poor aerodynamic stability caused by the matched work of the gas compressor and the turbine; and the engine can better work under different loads, thereby simplifying a structure of the engine, avoiding the surge phenomenon of the gas compressor, and increasing the work scope and the reliability.

Description

(1) Technical field: [0001] The invention relates to the field of aeroengines, especially jet engines. (two) background technology: [0002] The jet engine that the continuous jet that aviation vehicle adopts produces thrust is mainly turbojet engine, and turbofan engine is similar to turbojet engine, all is to generate thrust by high-speed exhaust, but the structure is more complicated. The turbojet engine has the characteristics of small size, light weight, and high thrust. However, the exhaust velocity at the outlet of its tail nozzle is high. When the aircraft is flying at low speed, the propulsion efficiency of the engine is low and the fuel consumption rate is high. The exhaust velocity of a turbofan engine is less than that of a turbojet engine, and its propulsion efficiency is higher than that of a turbojet engine when flying at a low speed, but the propulsion efficiency will decline when flying at a high speed. [0003] The turbojet engine of prior art is made up o...

AI Technical Summary

Problems solved by technology

A high boost ratio requires more stages of compressors to be realized, which will lead to lengthening of the connecting shaft between the compressor and the turbine, and high gas temperature requires high-performance high-temperature-resistant materials, which makes the structure of the engine complex and technically difficult , increased processing costs, reduced structure and strength reliability

In addition, since the output power of the turbine is restricted by factors such as the flow rate of the compressor, the boost ratio, the outlet temperature of the combustion chamber, and the rotational speed of the rotating shaft, there is a problem of matching the work of the compressor and the turbine.

The high boost ratio and many stages lead to the decrease of the aerodynamic stability of the compressor at low speed, and unstable working states such as rotating stall and surge

In order to alleviate the stability problem of the compressor at low speed, the turbojet engine often needs to adopt measures such as multi-stage compressor intermediate stage discharge, multi-rotor (double rotor or three rotor), adjustable inlet guide vanes and stator blades, etc. Prevent compressor surge, make the structure and control system of the engine more complicated

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