JPH02283822A - Variable cycle engine - Google Patents

Abstract

PURPOSE:To reduce the exhaust noise especially by using air for rotating a fan of an auxiliary propulsion device after passing high pressure air from a main compressor to a sub-compressor of a by-pass passage at the time of low speed, and by exhausting the high pressure air from the main compressor, from a main passage at the time of high speed. CONSTITUTION:A main compressor 3 is arranged in the front between an outer cylinder 1 and an inner cylinder 2, and a main passage 4 at the downstream side of the main compressor 3. At the downstream side of the main passage 4, a sub-passage 6 which is communicated with the main passage 4 is arranged through a primary shutter 5. There is provided a by-pass passage 9 which is communicated with the main passage 4 through a secondary shutter 7, and with the sub-passage 6 through a third shutter 8. A main combustion chamber 10 and a main turbine 11 are arranged at the sub-passage 6, and a sub- compressor 12, a sub-combustion chamber 13 and a sub-turbine 14 are arranged at the by-pass passage 9. A duct 15 is connected to the downstream side of the sub-compressor 12, and the duct 15 is connected to the auxiliary propulsion device 17 through a high pressure air controller 16.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a variable cycle engine having a main engine and an auxiliary propulsion device.

(Prior Art) High-speed commercial transport aircraft are equipped with, for example, a turbojet engine or a low bypass ratio turbofan engine as a motive power for propulsion. A turbojet engine adds fuel to air compressed by a compressor.
It is burned in a combustion chamber to create high-temperature gas, which turns a turbine to drive a compressor, which is then ejected from a nozzle, producing propulsive force as a reaction.

(Problems to be Solved by the Present Invention) Supersonic engines used in high-speed civil transport aircraft have extremely loud exhaust noise during takeoff. For this reason, high-speed commercial transport aircraft using supersonic engines tend to be prohibited from taking off and landing at airports with severe exhaust noise, and reducing exhaust noise has become an important issue.

Therefore, an object of the present invention is to reduce the above-mentioned exhaust noise.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a main passage leading to the exhaust side of the main compressor, a sub passage branching from the main passage via a first shutter, and a main passage. a bypass passage freely communicating with the auxiliary passage through a second shutter and a third shutter with respect to the auxiliary passage; a main combustor and a main turbine disposed in the auxiliary passage;
A main engine consisting of an auxiliary compressor, an auxiliary combustor, and an auxiliary turbine arranged in a bypass passage; an auxiliary combustor and an auxiliary turbine that receive part of the high-pressure air from the auxiliary compressor through a duct;
A variable cycle engine having an auxiliary propulsion device having a fan driven by an auxiliary turbine.

(Function) In the present invention, in low speed mode such as during takeoff and landing, high pressure air from the main compressor passes through the auxiliary compressor in the bypass passage, and part of it passes through the auxiliary combustion chamber and the auxiliary turbine, and between the main combustion chamber and the main turbine. The remaining part is used to rotate the fan of the auxiliary propulsion device via a duct. A fan creates auxiliary thrust.

Thus, in the low speed mode, the engine of the present invention is driven as a high bypass ratio turbofan engine with good propulsive efficiency and low noise at low speeds.

On the other hand, in high-speed mode, part of the high-pressure air from the main compressor is discharged from the main passage to create thrust, and the rest enters the auxiliary passage and passes through the main combustion chamber and main turbine to create thrust. used for. That is, in high speed mode, the engine of the present invention is driven as a low bypass ratio turbofan engine.

(Example) Refer to FIG. A main compressor 3 is disposed at the front between an outer cylinder 1 and an inner cylinder 2. A main passage 4 along the inner wall of the outer cylinder 1 is created on the downstream side of the main compressor 3. The first one is located downstream of the main passage 4.
A sub passage 6 is provided which can freely communicate with the main passage 4 through a shutter 5. A bypass passage 9 is provided which can freely communicate with the main passage 4 through a second shutter 7 and with the sub passage 6 through a third shutter 8.

A main combustion chamber 10 and a main turbine 11 are arranged in the sub passage 6. or,
A subcompressor 12, a subcombustion chamber 13, and a subturbine 14 are arranged in the bypass passage 9. The main turbine 11 drives the main compressor 13 and the auxiliary turbine 14 drives the auxiliary compressor 12.

A duct 15 is connected to the downstream side of the sub-compressor 12 to enable partial discharge of high-pressure air.

The duct 15 is connected to one or more auxiliary propulsion devices 17 via a high-pressure air control device 16 as required. The auxiliary propulsion device 17 includes a fan 19 in the shroud 18,
It has an auxiliary turbine 20 that drives a fan 19, and an auxiliary combustion chamber 2 that imitates the auxiliary turbine 20 and produces high-temperature gas. High pressure air from duct 15 is supplied to auxiliary combustion chamber 21 .

The high pressure air control device 16 controls the pressure, flow rate, temperature, etc. of high pressure air.

(Effects) The auxiliary propulsion system of the present invention can be applied to takeoff and landing as shown in FIG. It has the advantage of being able to cruise at supersonic speeds.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an engine according to an example of the present invention, Fig. 2 is a sectional view of the engine in high speed mode, Fig. 3 is a sectional view of the engine in low speed mode, and Fig. 4 is a perspective view showing a practical example. It is. In the diagram: 3.12... Compressor, 4... Main passage, 5, 7
゜8...Shutter, 6...Sub-passage, 9...Bypass passage, 10, 13. 21... combustion chamber, 11.
14. 20-...Turbine, 15...Duct, 19
···fan.

Claims (2)

[Claims] (1) A main passage leading to the exhaust side of the main compressor, a sub passage branching from the main passage via a first shutter, a second shutter for the main passage, and a third shutter for the sub passage A main engine consisting of a bypass passage that can freely communicate with each other, a main combustor and a main turbine arranged in the auxiliary passage, a auxiliary compressor, an auxiliary combustor, and an auxiliary turbine arranged in the bypass passage; A variable cycle engine having an auxiliary combustor, a portion of which is ducted, an auxiliary turbine, and an auxiliary propulsion device having a fan driven by the auxiliary turbine. (2) The variable cycle engine according to claim 1, wherein high pressure air is supplied to the duct in the low speed mode.