RU2278986C1 - Combination air-jet engine - Google Patents

Abstract

FIELD: mechanical engineering; air-jet engines.

SUBSTANCE: proposed combination air-jet engine contains compressor, primary combustion chambers, gas turbine and reaction nozzle. Outlet combustion chamber arranged after gas turbine and before reaction nozzle communicates either simultaneously or separately with independent gas-air channels provided with separate inlet holes. First of these channels is arranged along engine axis and it is provided with controllable shutoff gate installed on inlet hole and also compressor, primary combustion chambers and gas turbine arranged successively along said axis. Second channel is air duct whose inlet hole is furnished with controllable shutoff gate and pointed to side of front part of engine. Air is arranged along sides of engine, and its outlet hole is arranged over circle in side walls of outlet combustion chamber for directing air flows from air duct concentrically to center of outlet combustion chamber with collision, relative braking and turning of kinetic energy of air flows into additional compression. Outlet combustion chamber is furnished with nozzle to deliver fuel to maximum air compression area.

EFFECT: increased economy of engine.

3 cl, 1 dwg

Description

The invention relates to jet propulsion systems and is intended for use in flight aircraft, mainly high-speed aircraft, in airspace.

A ramjet is known as a ramjet engine, behind which there is a diffuser behind its inlet, which provides air compression with its high-pressure head, behind which there is a combustion chamber and a jet nozzle (see "Polytechnical Dictionary" edited by A.Yu. Ishlinsky, ed. "Soviet Encyclopedia", M. - 1980, pp. 420-421).

The disadvantages of the ramjet include the possibility of its use only at a flight speed equal to 2-3.5 sound speeds, and the need to use when using ramjet launch device for takeoff and acceleration of the aircraft to the required flight speed.

Also known is a turbojet engine (turbojet engine) containing a compressor, combustion chambers, a gas turbine and a jet nozzle with the possible use of an afterburner chamber also located behind the gas turbine (see also pages 544-545 and 566).

The disadvantage of turbojet engines is its lower efficiency compared to ramjet engines at high flight speeds and the need to supply an additional mass of air through the compressor when burning fuel in the afterburner, which leads to the need to complicate the compressor device and increase the power of the gas turbine with a corresponding increase in engine mass .

The present invention in the form of a combined air-jet engine (hereinafter referred to as the ASJC) allows to obtain a technical result consisting in the possibility, like ramjet engine, of compressing air without using a compressor when the aircraft is flying at high speed and the ability to provide take-off and acceleration of the aircraft using the proposed ASJC starting device. At the same time, the high-pressure rocket engine, like the ramjet engine, provides higher efficiency compared to the turbojet engine with a flight speed of 2-3.5 sound speeds (see ibid., P. 420).

The specified technical result is achieved by the use of an air-breathing turbojet engine containing a compressor, primary combustion chambers, a gas turbine and a jet nozzle. According to the invention, an exhaust combustion chamber is arranged behind the gas turbine and in front of the jet nozzle, which communicates simultaneously or separately-separately with separate and independent from each other gas-air channels having separate inlet openings. The first of these channels is placed along the axis line of the engine and contains a controlled shut-off valve installed on its inlet and also a compressor, primary combustion chambers and a gas turbine sequentially placed along the axis line. The second channel is an air duct, the inlet of which is equipped with a controlled shutter damper, facing the front of the engine and together with the air duct provides the possibility of preliminary air compression due to the high-pressure head of its oncoming flows during flight of the aircraft. The mentioned duct is located along the sides of the engine and its outlet is located in a circle in the side walls of the exhaust combustion chamber with the possibility of directing air flows from the duct concentrically to the center of the exhaust combustion chamber with their collision, mutual braking and conversion of the kinetic energy of these air flows into additional compression. The exhaust combustion chamber is equipped with a nozzle for supplying fuel to the area of greatest air compression.

As a special case, the air duct is made in the form of an annular air duct arranged uniformly on all sides from the outer side of the engine with inlet and outlet openings circular with respect to the axis of the engine axis.

As a special case, the air duct is made of several equally sized pipes placed on the external side of the engine, uniformly in circle, with their inlet and outlet openings and the above-controlled controlled shutter dampers.

In the drawing, in section along the axial frontal plane, a general view of the air-breathing apparatus is shown. The arrows in the drawing show the direction of movement of air and combustion products.

The ASJC comprises a compressor 1, primary combustion chambers 2, a gas turbine 3 and a jet nozzle 4. Behind the gas turbine and in front of the jet nozzle, an output combustion chamber 5 is arranged that communicates with the nozzle 4 and at the same time, or separately, with independent and independent from each other by gas-air channels having separate inlet openings. The first of these channels 6 is located along the line of the 0-0 axis of the engine and contains a controlled shut-off valve 7 installed on its inlet and also compressor 1, primary combustion chambers 2, and a gas turbine 3, in aggregates constituting a combination of similar parts of a turbojet engine with similar operating features. The second channel is an air duct 8, the inlet 9 of which is equipped with a controlled shutter 10, facing the front of the engine and together with the air duct 8 provides the possibility of preliminary compression of air due to the high-pressure head of its oncoming flows during flight of the aircraft. Said duct 8 is arranged along the sides of the engine and its outlet 11 is arranged in a circle in the side walls of the exhaust combustion chamber 5 with the possibility of directing air flows from the duct 8 concentrically to the center of the exhaust combustion chamber with their collision, mutual braking and conversion of the kinetic energy of these air flows into extra compression. The exhaust combustion chamber is equipped with a nozzle 12 for supplying fuel to the area of greatest air compression.

As a special case, the air duct 8 is made in the form of an annular air duct arranged uniformly on all sides from the outer side of the engine with inlet 9 and outlet 11 openings that are circular relative to the axis of the 0-0 axis of the engine.

As a special case, the air duct 8 is made of several pipes of the same size and shape placed on the outer side of the engine in a circle with their inlet 9 and outlet 11 openings and the aforementioned controlled shut-off valves 10.

As a special case, the controlled shutter 7 of the first channel 6 is made in the form of a conical nose cone of the engine, closing the entrance to the first channel when in the forward position. When moving the said cone of the fairing within the cavity of the first channel 6, it is combined with the gap with the front of the compressor housing and allows air to enter the first channel. In order to increase the reliability of operation, the movement of the cone of the fairing is made on a fixed guide rod 13.

As a special case, the controlled shut-off valve 10 of the duct 8 is made in the form of a profiled plate connected externally to the motor housing by means of a hinge (for example, in the form of an axis) with the possibility of rotation with overlapping of the air inlet to the duct.

CERD creates jet thrust as follows.

The capabilities typical for turbojet engines are used at the start of acceleration and flight of the aircraft. In this case, with the help of the compressor 1, air is compressed, which, together with the fuel supply, is sent to the primary combustion chambers 2. A gas turbine 3 is used as a compressor drive, behind which it is possible to burn fuel in the exhaust combustion chamber 5.

The difference between the output combustion chamber 5 in the CVAC from the known afterburner, which is part of the turbojet engine, in design and operation features is that the output combustion chamber directly communicates with atmospheric air, the compression of which is carried out in the above input device 9 and the duct due to the high-speed the head of the oncoming air flows during the flight of the aircraft and is further increased by creating oncoming air flows in the combustion chamber itself. In contrast, compressed air enters the afterburner chamber of the turbojet engine from the compressor. This difference provides the possibility of operation of the high pressure airjet in the ramjet mode, which is more economical compared to the mode of operation of the turbojet engine.

In CERD, three main operating modes are applied.

The first mode of operation is similar to the mode of operation of the turbojet engine and is used mainly at launch, acceleration and flight of an aircraft with a speed lower than that necessary for operation in ramjet operation mode. In this case, the controlled shutter valve 7 of the first channel 6 is open, which provides free air access to the first channel and then through the compressor 1 to the primary combustion chambers 2, and the gas formed in them due to fuel combustion is directed to the gas turbine 3 and then through the exhaust combustion chamber 5 - into the jet nozzle 4 with the creation of jet thrust. In this case, additional combustion of fuel in the exhaust combustion chamber is possible with its supply through the nozzle 12. In this operating mode, the controlled shut-off valve 10 of the duct 8 is closed.

The second mode of operation is carried out with open controlled shutter dampers 7 and 10 of the first channel 6 and air duct 8 with fuel burning in the primary combustion chambers 2 and the exhaust combustion chamber 5. This operating mode is used mainly for afterburner and short-term operation during the transition from one of the operating modes another.

In the third mode of operation, the most economical mode of ramjet operation is carried out. It is used only at high flight speeds. In this case, the controlled shutter 7 of the first channel 6 is closed, the first channel is isolated, and air does not enter it. The air in the above order in the form of oncoming flows during the flight of the aircraft enters the exhaust combustion chamber only from the duct 8, while the controlled shut-off valve 10 of the duct is open.

Taking into account the above-mentioned operating features, the air-breathing engine possesses the capabilities of a ramjet engine and, at the same time, provides takeoff and acceleration of the aircraft to the required flight speed without the use of a launch device, and has increased efficiency compared to a turbojet engine at high flight speeds.

Claims (3)

1. A combined jet engine comprising a compressor, primary combustion chambers, a gas turbine and a jet nozzle, characterized in that an output combustion chamber is arranged behind the gas turbine and in front of the jet nozzle, which communicates simultaneously or separately or separately with separate and independent other gas-air channels having separate inlet openings, the first of these channels is placed along the line of the axis of the engine and contains a controllable stopper mounted on its inlet a damper, as well as a compressor, primary combustion chambers and a gas turbine sequentially placed along the axis line, and the second channel is an air duct, the inlet of which is equipped with a controlled shutter damper, facing the front of the engine and together with the air duct provides the possibility of preliminary air compression due to the pressure head of its oncoming flows during the flight of the aircraft, said duct is placed along the sides of the engine, and its outlet p It is arranged in a circle in the side walls of the exhaust combustion chamber with the possibility of directing air flows from the duct concentrically to the center of the exhaust combustion chamber with their collision, mutual braking and transformation of the kinetic energy of these air flows into additional compression, the exhaust combustion chamber is equipped with a nozzle for supplying fuel to the region of greatest air compression. 2. The engine according to claim 1, characterized in that, as a special case of the execution of the duct made in the form of placed evenly on all sides from the outer side of the motor ring duct with circular in relation to the axis of the engine inlet and outlet openings. 3. The engine according to claim 1, characterized in that as a special case of the execution of the duct is made of placed on the outer side of the engine uniformly in a circle of several pipes of the same size and shape with their inlet and outlet openings and the above-controlled controlled shutter dampers.