RU2456569C1 - Apparatus for ground tests on power installation in aircraft - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: sensors for the measured characteristic of the power installation are in form of sensors of the strength of infrared radiation of the power installation into the atmosphere which are mounted on an aircraft. The air stream generator used is part of engine unit of an auxiliary aircraft mounted in front of the aircraft on one half-wing of the auxiliary aircraft such that its longitudinal axis lies near the vertical plane of symmetry of the power installation of the aircraft, in front of which a deflector is mounted with a gap and at an angle to the ground.

EFFECT: invention enables to obtain the characteristic of strength of infrared radiation of the power installation using a much simpler device with low capital-output ratio of the device, low cost of the tests themselves and high reliability of the obtained results.

5 cl, 4 dwg

Description

The invention relates to the field of special tests of aircraft gas turbine engines, in particular, to devices for conducting ground tests of an engine in an aircraft for measuring the strength of infrared radiation into the atmosphere from a working engine.

A device is known at TsIAM for measuring infrared radiation (IR radiation) (See “IR — Visibility of Output Devices,” “Scientific Contribution to the Development of Aircraft Engines,” book 1, p. 349, M .: Mechanical Engineering, 2000).

The disadvantage of this device is that there is no blowing of the engine by an external flow, which leads to a distortion of the results and their unreliability.

The closest solution to the achieved effect is the device - “T-104 Subsonic Wind Tunnel” for ground tests of the power plant as part of the aircraft, containing an air flow generator located in front of the aircraft with the tested power plant, and sensors of the measured power plant characteristics (See Web page: http://www.tsagi.ru Section "Experimental base").

The disadvantage of this technical solution is the inability to place infrared radiation sensors at the required distance from the tail of the aircraft, when the strength of its infrared radiation to the atmosphere is selected as the measured characteristic of the power plant. In addition, wind tunnels have a closed circuit, which leads to the accumulation of aerosol in the stream and, accordingly, to distort the real picture if aerosols are used as protection against infrared radiation.

Possible improvements to wind tunnels in terms of their transition to an open circuit are irrational due to the high capital intensity and cost of such projects. Tests of this kind are carried out when creating a new aircraft, which are created at a fairly large time interval, so the creation of such capital stands is irrational.

The technical effect of the present invention is to obtain the characteristics of the infrared radiation power of the power plant by the simplest device for ground testing of the power plant as part of an aircraft with a decrease in the capital consumption of the device, a decrease in the cost of the tests themselves and an increase in the reliability of the results obtained, as well as the possibility of placing infrared sensors required distance.

The technical effect of the present invention is achieved by the fact that in the device for ground testing of the power plant as part of an aircraft containing an air flow generator located in front of the aircraft with the tested power plant, and sensors of the measured characteristics of the power plant, in it sensors of the measured characteristics of the power plant are made in the form of sensors of the infrared radiation power of a power plant in the atmosphere installed behind the aircraft, and as a generator airflow selected portion of the auxiliary propulsion of the aircraft, installed in front of the aircraft at a hemipteran auxiliary plane so that its longitudinal axis is placed near the vertical plane of symmetry of the propulsion system of the aircraft, in front of which a gap at an angle to the ground mounted deflector.

Besides:

- part of the propulsion system of the auxiliary aircraft can be made of two adjacent propeller engines or gas turbine engines with a large degree of bypass;

- the deflector can be made hollow and open from the ends, and perforation is made on the lower surface of the deflector;

- the deflector can be made sectional with an adjustable angle;

- transverse power set of the deflector - ribs can be made outside the deflector.

The use of infrared radiation force sensors as sensors of the measured characteristics of the power plant and the installation of these sensors behind the aircraft allows you to measure in full the characteristics of the infrared radiation of the power plant.

The use of a part of the propulsion system of the auxiliary aircraft installed in front of the aircraft as an airflow generator makes it possible to measure the characteristics of the infrared radiation of the propulsion system with the simplest device at the lowest cost and lower cost of the tests themselves, since it is intended to use the auxiliary aircraft only for the duration of the tests themselves .

The implementation of a part of the propulsion system of an auxiliary aircraft from two adjacent rotary engine engines or gas turbine engines with a high bypass ratio allows blowing the aircraft with the tested power plant with cooler air, as well as expanding the number of aircraft suitable for use as an auxiliary aircraft.

Placing the longitudinal axis of the part of the propulsion system of the auxiliary aircraft near the vertical plane of symmetry of the tested power plant of the aircraft brings the test conditions closer to the actual conditions of the air flow around the aircraft during flight and thereby increases the reliability of the tests.

Installation in front of the aircraft with a gap at an angle to the ground of the deflector allows you to most rationally and at the right angle to direct the air created by part of the propulsion system of the auxiliary aircraft to blow around the aircraft, simulating the actual flight conditions of the aircraft.

The execution of the deflector hollow and open from the ends and perforated allows you to implement a scheme with the intake of cold air through the ends of the deflector and its discharge through the perforation into the rarefaction area under the deflector. The mixture of sucked-in cold air and part of the gases of the hot stream reduces the temperature of this part of the hot stream. Accordingly, the temperature of the air entering the air intakes of the aircraft with the tested power plant is reduced to an acceptable level.

The design of the deflector sectional and with an adjustable angle allows you to direct the air flow to the aircraft at the angles necessary for testing.

Figure 1 shows a General view of the device.

Figure 2 shows a side view from above on the deflector.

Figure 3 shows a side view from below on the deflector.

Figure 4 shows a diagram of the flow around the deflector in side view.

A device for ground testing of a power plant as part of an aircraft contains an air flow generator made as part of a propulsion system consisting of two propeller engines 1 of an auxiliary aircraft 2, located in front of the aircraft 3 with the tested power plant 4, and infrared radiation sensors 5 in atmosphere installed behind the aircraft 3. The longitudinal axis 6 of the two propellers 7 of the propeller engines 1 of the auxiliary aircraft 2 is located near the vert focal plane of symmetry 4 of the power plant of an aircraft before the aircraft 3. 3 h with clearance angle α is set to the ground deflector 8 formed as a hollow inverted wing. The deflector 8 is made open from the ends 9, and a perforation 11 is made on its lower surface 10. The deflector 8 is broken by ribs 12 into sections. There is a screw device 13 for adjusting the angle of inclination α. The ribs 12 are made outside the deflector 8. The perforation 11 communicates with the open ends 9 of the deflector 8. In the front part of the deflector section, using pins 14, they are connected to the brackets 15 mounted on the foundation 16. The brackets 15 can be adjusted in height using special gaskets, which makes it possible change the amount of clearance h between the deflector 8 and the ground. Behind the deflector 8, an aircraft 3 with an aerosol protection system is installed on a special stand or on its own landing gear. In an arc, from the angles of interest to researchers, infrared radiation force sensors 5 are installed.

Part of the propulsion system of the auxiliary aircraft 2 can be made in the form of two adjacent gas turbine engines with a large degree of bypass (not shown in the drawings).

The device operates as follows.

The deflector 8 using special pads for the brackets 15 is installed with a given gap h and is set using a screw device 13 to adjust the angle to the required angle α. Thus, it is possible to fine-tune the device for ground testing of the power plant in the aircraft under the geometric dimensions and characteristics of the aircraft 3.

Then, the auxiliary aircraft 2 is exposed in front of the deflector 8 so that the longitudinal axis 6 of the two propellers 7 passes through the middle of the length of the deflector 8. The aircraft 3 with the tested power unit 4 is installed behind the deflector 8 in its designated place. At the same time, it can stand on its own chassis or on a special stand. Then start the power plant of the aircraft 3 and two propeller engines 1 of the auxiliary aircraft 2. The air flow from the propeller engines 1 at a distance of 3-5 calibers of the air stream is sucked to the ground. Passing above and below the deflector 8, the flow deflects upward at an angle β, takes off from the ground and flows around the aircraft 3, simulating flight conditions. The hot exhaust stream of a part of the propulsion system of the auxiliary aircraft 2 is partially mixed with the cold stream from the propeller 7, and partially retains its core. To eliminate the surge of the tested power plant 4, a circuit was implemented with the intake of cold air through the ends 9 of the deflector 8 and its discharge through the perforation 11 into the vacuum region under the deflector. The mixture of sucked-in cold air and part of the hot stream reduces the temperature of this part of the hot stream. Accordingly, the temperature of the air entering the air intakes of the aircraft 3 is reduced to an acceptable level. During operation of the tested power plant 4, the signal is recorded from the sensors measuring the strength of infrared radiation 5, by decoding of which it is possible to judge the infrared visibility of the tested power plant.

The proposed invention greatly simplifies the device, reduces its capital intensity and reduces cost. The number of units that make up the device is reduced. At the same time, an airplane temporarily removed from flight operation (2-3 hours) is used to create an air flow without modifications. A very important effect is to prevent the ingress of hot air from the engines of the auxiliary aircraft into the air intakes of the aircraft with the power plant under study, as well as the possibility of placing infrared radiation sensors at the required distance from the tail of the aircraft with the power plant under study.

Claims (5)

1. A device for ground-based testing of a power plant as part of an aircraft, comprising an air flow generator located in front of the aircraft with a test power plant, and sensors of a measured power plant characteristics, characterized in that the sensors of the measured power plant characteristics are made in the form of infrared radiation force sensors power plant in the atmosphere installed behind the aircraft, and as a generator of the air flow selected part of the propulsion system and an auxiliary aircraft mounted in front of the aircraft on one half-wing of the auxiliary aircraft so that its longitudinal axis is located near the vertical plane of symmetry of the aircraft power plant, in front of which a deflector is mounted with a gap at an angle to the ground. 2. The device according to claim 1, characterized in that a part of the propulsion system of the auxiliary aircraft is made of two adjacent rotor engines or gas turbine engines with a large bypass ratio. 3. The device according to claim 1, characterized in that the deflector is hollow and open from the ends, and perforation is performed on the lower surface of the deflector. 4. The device according to claim 1, characterized in that the deflector is partitioned with an adjustable angle of inclination. 5. The device according to claim 1, characterized in that the transverse power set of the deflector - ribs are made outside the deflector.

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