RU2704381C1 - Aerodynamic control method of aircraft - Google Patents

Abstract

FIELD: aircraft control.

SUBSTANCE: invention relates to aerodynamic control of technical objects, mainly small-size aircrafts, flying with maneuvering at small angles of attack and sliding (for example, on straight or ballistic trajectories). For aerodynamic control of aircraft (1), air flow of cantilevers (2) is periodically extended into air stream flowing over the aircraft with their subsequent heating to initial position. At that, cantilevers (2) are arranged in aircraft (1) fuselage symmetrically to its pitch plane. Extending each console (2) is performed by 10…100 % of its span with frequency of input into air flow of up to 200 Hz. Console (2) cross-section is provided with configuration of flat plate or aerodynamic profile. On aircraft (1) there are at least two pairs of consoles (2). Console (2) of each pair is unfolded until their average aerodynamic chords (ACC) angle ±(0.5…45) degrees relative to the plane of symmetry of the pair parallel to aircraft longitudinal axis. At least two cantilevers (2) are simultaneously introduced into the air flow that flows around the aircraft.

EFFECT: efficient aerodynamic control of aircraft in "relay" mode without speed losses at intensive standard operation and with possibility of arrangement of aerodynamic steering wheels not on planes, and in fuselage, more dense in comparison with traditional schemes of folding aerodynamic rudders configuration, smaller structural complexity and power consumption of drives, absence of specialized systems of opening (including synchronous) and fixation of rudder cantilevers, convenience of sealing (for example, film ring), increased overall reliability during storage and operation.

9 cl, 7 dwg

Description

The invention relates to the aerodynamic control of technical objects, mainly small-sized aircraft (LA), flying with maneuvering at small angles of attack and glide (for example, along straight or ballistic trajectories).

Known methods of aerodynamic control (stabilization of motion) of an aircraft by means of rudders, shields, rollers, interceptors, transformable (e.g., slotted) wing mechanization organs, brake parachutes - see, for example, N.F. Krasnov, V.N. Koshevoy, A.N. Danilov, V.F. Zakharchenko "Aerodynamics of rockets", M., "Higher School", 1968, pp. 62-67. At the same time, the complexity of the practical implementation of the indicated methods of aerodynamic control of aircraft is dramatically different: from episodic discrete actions (for example, by interceptors) to continuous adaptive operation in air flows of various intensities, including under conditions of interference, shading, and beveling (for example, all-turning aerodynamic rudders).

Known simple in practical implementation of the method of "relay" aerodynamic control of an aircraft by means of interceptors (the closest analogue). The extended interceptor creates a stall of the air flow on the wing surface of the aircraft, and also forms a region of inhibition of the flow in front of the interceptor. At the same time, the aerodynamic characteristics of the wing “change” —the lifting force decreases and the resistance increases (see, for example, A.K. Martynov “Applied Aerodynamics”, M., “Mechanical Engineering”, 1972, pp. 417, 422-424).

The disadvantages of the closest analogue include the impossibility of full control of the aircraft in the absence of wings on it (bearing aerodynamic surfaces), as well as significant loss of speed of the aircraft with intensive regular operation of the interceptors.

The technical task of the invention is the creation of a method of efficient aerodynamic control of the aircraft in the "relay" mode, similar in technical features to the operation of interceptors (and therefore simple in practical implementation, for example, on small wingless aircraft), but devoid of the shortcomings of the closest analogue (placement only on planes, speed loss during intensive regular work).

The solution of this technical problem is achieved by the fact that the console of the aerodynamic rudders is placed in the aircraft fuselage (in the recessed starting position) symmetrically to its pitch plane, each console is extended by 10% ... 100% of its span with a frequency of entry into the air flow of up to 200 Hz, cross section the consoles give the configuration of a flat plate or aerodynamic profile, at least two pairs of consoles are placed on the aircraft, and the consoles of each pair are deployed until their average aerodynamic chords (SAX) reach an angle of ± (0.5 ... 45) g adusov pair relative to the plane of symmetry parallel to the longitudinal axis LA, the LA in ambient air stream is introduced simultaneously at least two consoles. The minimum (10% of range) extension of the console is set at a level of at least 1% of the distance from its leading edge to the nose of the aircraft. The steering console along the span can have an aerodynamic and / or geometric twist, while in the process of extension and sinking the console with a geometric twist, it is rotated about an axis parallel to the span. In some cases, the SAX spell angle of each console smoothly or discretely with a step of at least 0.1 angular degrees is changed directly during the flight of the aircraft. The simultaneous extension of the consoles perform the same or unequal value within the range of their permitted ranges. Variants of practical implementation: the console is pushed into the air stream and recessed into the aircraft body by means of the force of a linear electromagnet, while in the extreme end positions the console is stopped by means of a mechanical damper-damper; the console is connected to a linear electromagnet by means of a rocking chair. It seems advisable in the pre-launch position to recess the recessed console using a breakthrough film ring.

In FIG. 1, 2 presents a technical solution for implementing the proposed method on an axisymmetric aircraft of the type of tactical projectile (missile), in FIG. 3, 4 - symmetric and asymmetric cross-sectional profiles of the console of the aerodynamic steering wheel, in FIG. 5 - allowable angular position of the SAX console in flight, in FIG. 6, 7 - options for the practical implementation of the mechanism of extension / sinking console. It seems appropriate to name the class of devices that implement the proposed method of aerodynamic control of aircraft, diving rudders (HP).

Designations accepted:

1 - body (fuselage carrying a structural element) of the aircraft;

2 - console;

3 - anchor linear electromagnet;

4 - coil linear electromagnet;

5 - damper shock absorber;

6 - a rocking chair;

7 - mechanism for turning the MARX console;

8 - breakthrough film ring (membrane);

R is the distance from the nose of the aircraft to the front edge of the console;

NP - flight direction of the aircraft.

The functioning of technical devices in the framework of the proposed method of aerodynamic control is as follows. In the initial (recessed in the body pos. 1 aircraft) position of the console pos. 2 diving rudders are arranged in pairs in one or more transverse planes of the body, pos. 1 (see Fig. 1, 2). In the process of controlling the aircraft in flight, at the commands of the onboard control system, at least two consoles pos. 2, as a rule, from different pairs - how is the formation of aerodynamic forces and moments corresponding in value and direction of action achieved. In this case, the extension of each console pos. 2 into the stream can be carried out within the range of allowed ranges - namely, from 10% to 100% of its full (maximum) range. It should be noted that the extension of the console pos. 2 by the minimum length (10% of its full scale) correlates with the thickness of the boundary layer (amounts to ~ 1% of the distance R from the nose of the aircraft) to implement effective control actions. Moreover, the indicated dependence of the boundary layer thickness on R is fulfilled (with an acceptable error) for aircraft with high subsonic and supersonic flight speeds. For aircraft with low and ultra-low speeds, where air viscosity begins to appear, the proposed technical solution with a minimum console span pos. 2 will play the role of an additional turbulizer (which positively affects the overall controllability of the aircraft at low - significantly lower than 100,000 - Reynolds numbers).

A characteristic aspect of the proposed technical solution should be considered the input frequency of the consoles pos. 2 into the air stream. Depending on the dimension of HP, the aircraft as a whole and its speed (respectively, the Reynolds number), it is practically expedient for modern and promising ones, including ultra-small aircraft can be considered the value of the extension frequency of the consoles pos. 2 to 200 Hz.

It should be noted that the proposed technical solution is also efficient when using jet engines in axial compressors and turbines, for example, when transforming turbojet engines into direct-flow engines when speeding up by hypersonic aircraft.

Cross section of the console pos. 2, depending primarily on the speed of the aircraft and the estimated angle of installation of the console relative to the NP, it is advisable to give one or another specialized configuration, for example, a plate, a symmetric or asymmetric aerodynamic profile (see Fig. 3, 4). In this way, the interaction of the console pos. 2 with free air flow, and accordingly the aerodynamic efficiency of HP aircraft increases (which fundamentally distinguishes the work of HP from the functioning of interceptors with stall).

In addition, an additional console pos. 2 may have an aerodynamic (combination of profiles of various configurations) and / or geometric (twist of the end parts of the console relative to the root) twist along the span. Moreover, in the process of extension / extension of the console pos. 2 with a geometric twist, its angular movement (turn) is made relative to an axis parallel to the span. This minimizes the width of the guide slot in the housing (power element) pos. 1 through which the console pos. 2 extends into the air stream.

Both rigidly fixed and angular orientation of the SAX consoles pos. 2 in the range of ± (0.5 ... 45) degrees relative to the plane of symmetry of the pair parallel to the longitudinal axis of the aircraft (see Fig. 5). In the latter case, each console pos. 2 (option: a pair of consoles assembled) is rotated smoothly or discretely with a pitch of at least 0.1 angular degrees through, for example, a specialized mechanism pos. 7. Thus, the entire range of HP operation, including the controlled stall mode, can be activated.

In the proposed method of aerodynamic control of an aircraft, the simultaneous extension or extension of at least two consoles poses should be the same or unequal in scope. 2 (usually different pairs) from the body pos. 1. In this case, in the case of unequal extension of the consoles, “combined” aircraft maneuvers can be implemented (simultaneously through several channels, for example, changing the pitch angle with the calculated slip, changing the course with correcting the roll, etc.).

The practical implementation of the proposed method of aerodynamic control of an aircraft can be carried out, for example, by installing the console pos. 2 on the movable anchor pos. 3 linear electromagnets, which with a given (including variable) frequency are moved (including to extreme positions) due to electromagnetic interaction with the coil pos. 4 linear electromagnets. Moreover, in the extreme end positions, the anchor pos. 3 with the console fixed to it pos. 2 shock absorbed by means of a mechanical (e.g. rubber) damper-damper pos. 5 (see Fig. 6, 7).

Coordination of traction and range of movement of the anchor pos. 3 linear electromagnets with the range of the allowed range of the console pos. 2 can be produced, for example, by connecting the console pos. 2 and anchors pos. 3 by means of a rocking chair pos. 6. In this case, the selection (adjustment) of the shoulders L ₁ and L ₂ relative to the axis of rotation of the rocking pos. 6 achieve optimal coordination parameters for specific aircraft samples (see Fig. 7).

Drives with variable stroke of the working rod and associated console pos. 2 (for example, based on traditional electric, or pneumatic, or hydraulic steering machines) provide both a variable range and a variable extension / extension frequency of the console pos. 2, including in the entire allowed range.

Pre-start sealing of recessed consoles pos. 2 it is advisable to carry out, for example, by means of breakthrough film rings (membranes) pos. 8, which cover the cross section of the housing pos. 1 aircraft in the plane (s) of the HP.

The application of the proposed technical solution is advisable, first of all, for small-sized container-based aircraft flying (including along ballistic and aeroballistic trajectories) with maneuvering at relatively small - for example, up to 10 ° ... 15 ° - angles of attack and slip. The advantages in this case will be a denser arrangement compared to traditional schemes of folding aerodynamic rudders, less structural complexity and power consumption of the drives, the absence of specialized opening systems (including synchronous) and fixation of the steering wheel consoles, the convenience of sealing (for example, with a film ring) , increased overall reliability during storage and operation due to the placement of consoles completely inside the aircraft body, etc. In the framework of the universal criterion “efficiency - cost - time spent”, the proposed technical solution forms a rational “ecological niche” between the well-known aircraft control methods: “complex”, but with low resistance losses through aerodynamic rudders and “simple” “relay” with speed loss through interceptors.

Claims (9)

1. The method of aerodynamic control of an aircraft is an aircraft, including the periodic extension of the consoles into the airflow around the aircraft with their subsequent recession into the initial position, characterized in that the consoles are placed in the aircraft fuselage symmetrically to its pitch plane, each console is extended by 10% ... 100 % of its span with an input frequency of up to 200 Hz into the air stream, a cross-section of the cantilever is configured as a flat plate or an aerodynamic profile, at least two pairs of cantilevers are placed on the aircraft, and if each pair deploy until reaching their mean aerodynamic chord - MAR angle ± (0,5 ... 45) degrees relative to the plane of symmetry of the pair parallel to the longitudinal axis LA, the LA in ambient air stream is introduced simultaneously at least two consoles. 2. The aerodynamic control method of an aircraft according to claim 1, characterized in that the minimum extension of the console is set at least 1% of the distance from its leading edge to the nose of the aircraft. 3. The aerodynamic control method of an aircraft according to claim 1, characterized in that the console along the span has an aerodynamic twist. 4. The aerodynamic control method of an aircraft according to claim 1, characterized in that the console along the span has a geometric twist, while in the process of extending and sinking the console with a geometric twist, it is twisted relative to an axis parallel to the span. 5. The aerodynamic control method of an aircraft according to claim 1, characterized in that the SAH spell angle of each console smoothly or discretely with a step of at least 0.1 angular degrees is changed directly during the flight of the aircraft. 6. The aerodynamic control method of an aircraft according to claim 1, characterized in that the simultaneous extension of the consoles is carried out at the same or unequal value within the range of allowed ranges. 7. The aerodynamic control method of an aircraft according to claim 1, characterized in that the console is pushed into the air stream and recessed into the aircraft body by the force of a linear electromagnet, while the console is stopped at the extreme end positions by means of a mechanical damper-damper. 8. The aerodynamic control method of an aircraft according to claim 7, characterized in that the console is connected to a linear electromagnet by means of a rocking chair. 9. The aerodynamic control method of an aircraft according to claim 1, characterized in that in the pre-launch position, the recessed console is sealed by a breakthrough film ring.

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