Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/04—Air intakes for gas-turbine plants or jet-propulsion plants
  • F02C7/057—Control or regulation
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/04—Air intakes for gas-turbine plants or jet-propulsion plants
  • F02C7/042—Air intakes for gas-turbine plants or jet-propulsion plants having variable geometry
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2220/00—Application
  • F05D2220/80—Application in supersonic vehicles excluding hypersonic vehicles or ram, scram or rocket propulsion

Definitions

• the invention relates to aircraft, in particular, to the air intakes of the power plants of supersonic aircraft.
• the preferred field of application of the invention are aircraft with turbofan engines with a maximum Mach number of not more than 3.
• the creation of an aircraft which is hardly noticeable in the radar range, implies that the shape of all its elements contributes to a decrease in the level of the effective scattering area (EPR) of the aircraft. This also applies to the intake form of the engine intake.
• EPR effective scattering area
• all edges of the air intake should have a sweep and be parallel to any elements of the aircraft (the edges of the wing, plumage, etc.).
• the implementation of such an air intake which has high internal characteristics in the entire operational range, is impossible without its regulation.
• Adjustable, as a rule, are the braking surfaces of the air intake (for example, a wedge or cone). At supersonic speeds, a change in the angle of the solution of the braking surface leads to a change in the intensity of braking of the flow in the air intake, as well as a change in the area of its throat. In total, the effect of such regulation allows to obtain high characteristics of the air intake in the entire range of flight speeds of the aircraft on which it is installed.
• a known method of regulating a supersonic flat (two-dimensional) air intake the braking surface of which is represented by a multi-stage non-sweep wedge (N. N. Remeev, “Aerodynamics of the air intakes of supersonic aircraft.” TsAGI Publishing House, Zhukovsky, 2002, 178 s).
• the regulation of the air intake is carried out using rotary relative to the respective axes of the panels.
• the panels are located in the channel one after another.
• the front panel contains the steps of the brake wedge, except for the first. Its axis coincides with the line of intersection of the first and second steps of the wedge.
• the back panel is part of the channel and has a complex shape.
• the axis of the rear panel extends over its trailing edge.
• the absence of sweep of the edge and the steps of the brake wedge allows the use of parallel to the axis of rotation of the panels, perpendicular free flow.
• the disadvantage of the method of regulating a flat air intake in relation to an air intake with swept edges is the impracticability of its regulation axes perpendicular to the direction of flow, because all elements of the air intake are sweep.
• a method for controlling a supersonic air intake is adopted, in which the throat area and the position of the shock waves are changed (RU 2343297 C1).
• spatial flow inhibition is realized through the use of a V-shaped wedge (i.e., two arrow-shaped wedges adjoining each other, oriented towards each other in a front view at an obtuse angle).
• the air intake is made sweeping all edges of the entrance.
• the regulation of the air intake is carried out using two pairs of panels that rotate relative to the respective axes.
• the front panels of each pair are part of the braking surfaces.
• the rear panels are part of the channel.
• the method of regulating the air intake does not provide the necessary throat area at subsonic and low supersonic flight speeds, because the amplitude of movement of the movable panels is small. Otherwise, the aforementioned longitudinal slots of unacceptable sizes arise. This means that the air intake does not provide the operation of the turbojet engine in the entire operational range of speeds and is not multi-mode.
• the technical result to which the invention is directed is to provide the possibility of changing the angle of the steps of one of the arrow-shaped braking wedges and the minimum passage area of the air intake (throat) without the formation of undesirable longitudinal gaps and seizing of moving elements in its channel.
• the specified technical result is achieved by the fact that in the method of controlling a supersonic air intake, in which the throat area and the position of the shock waves are changed, the throat area and the position of the shock waves are changed by simultaneously turning the front adjustable panel, the rotation axis of which coincides with the intersection line of the first and second stage one of the arrow-shaped wedges, not perpendicular to the incoming flow, and the rear adjustable panel, the rotation axis of which is located in the zones e of the trailing edge of the rear adjustable panel and is oriented based on the condition of a point of intersection with the axis of rotation of the front adjustable panel, while turning the front and rear adjustable panels, their side edges move relative to the profiled side surfaces of the channel without creating gaps between them.
• the orientation of the transverse gap between them in the top view does not change, and its position coincides with the straight line passing through the intersection of the rotation axes of the front and rear adjustable panels, while the gap has a shape close to rectangular for any possible position of the adjustable panels.
• the curtains are rotated relative to its axis of rotation and are oriented in such a way that they have a common intersection point between the wall and the axis of rotation of the rear adjustable panel.
• FIG. 1 shows an adjustable supersonic air intake - bottom view
• FIG. 2 adjustable supersonic air intake - side view
• FIG. 3 adjustable supersonic air intake - front view
• FIG. 4 is a section AA of FIG. one
• FIG. 5 is a braking diagram in a supersonic adjustable air intake at a design flight mode
• FIG. 6 is a plan view of a supersonic air intake and its control panels 5
• FIG. 7 is a side view of a supersonic air intake and control panels thereof
• FIG. 8 is a section BB in FIG. 6.
• the supersonic adjustable air intake contains the following elements:
• the front intake inlet form - a parallelogram or its special case - a rectangle, with an arbitrary ratio of its height and the length of the corresponding side. It is possible to perform trimming, for example, 19 and 21, or rounding corners, for example, 20 of the inlet of the air intake, with the exception of the angle formed by arrow-shaped wedges.
• the edges of the air intake inlet lie in a plane oriented to the direction of flow at an acute angle. Thus, all edges of the entrance have a sweep.
• the supersonic diffuser 24 is a flow braking system consisting of a pair of swept wedges 7 and 22, forming a dihedral angle and shells (3, 4 - the edges of the shell).
• Arrow-shaped wedges 7 and 22 have at least one step, while the number of steps on these wedges may not coincide.
• FIG. 1, 2, 3, 4 shows the air intake, which has three steps on one swept wedge and two on the second.
• the fractures of the corresponding steps 16, 17, 18 of the arrow-shaped wedges 7 and 22 intersect at a point lying on the intersection line of the surfaces of the corresponding steps of the wedges forming a dihedral angle.
• the sweep angles of the steps on each of the sweep wedges may differ from the sweep angle of the edge of the corresponding wedge, as well as between themselves.
• the solution angles of the steps of swept wedges are determined when constructing the braking system from the condition that each pair of corresponding steps of the wedges creates a single oblique shock wave of a given intensity, i.e. the principles of gas-dynamic design are used (Schepanovsky VA, Gutov BI “Gas-dynamic design of supersonic air intakes”. Nauka, Novosibirsk, 1993). Perforation may be performed on some steps of the swept wedges.
• the shell as well as swept wedges 7 and 22 forms a dihedral angle.
• a characteristic feature is the shell orientation in which it additionally inhibits the flow, i.e. the shell is not oriented along streamlines behind the shock waves from swept wedges.
• the angle of undercut of the shell may be variable. In the area of the dihedral angle formed by the shell, it is possible to organize a cutout in the edge of the inlet of the air intake, and in the shell itself, the placement of holes of arbitrary shape is possible.
• air supply flaps 8 providing access of an external stream of air flowing around the air intake to the subsonic diffuser 25.
• the make-up flaps 8 contribute to an increase characteristics of the air intake at low speeds (take-off modes and flight modes at high angles of attack).
• the method of controlling the above-described air intake is as follows.
• the front adjustable panel 1 containing the steps of one of the arrow-shaped wedges 7, except for the first one, rotates relative to the axis 9 located at the intersection of the first and second steps of the wedge 7.
• the response rear adjustable panel 12 is part of the subsonic diffuser 25 and rotates around the spatially located axis 10 . If the axis 9 of the front adjustable panel is uniquely defined, then the choice of the orientation of the axis 10 of the rear adjustable panel passing over its trailing edge is determined from the condition of intersection of the axis 10 of the rear adjustable panel adjustable panel with axis 9 of the front adjustable panel 1 1.
• the transverse gap between them has a shape close to rectangular.
• the front adjustable panel 1 1 is connected to the rear adjustable panel 12 via rods 43.
• the front 1 1 and rear 12 adjustable panels When adjusting the air intake, the front 1 1 and rear 12 adjustable panels, turning, simultaneously change their position in accordance with the given law.
• the panels 11 and 12 When the panels 11 and 12 are rotated, the area of the throat of the air intake changes, the angle of the moving steps of the swept wedge 7, the size of the transverse drain slit 15 between the panels 1 1 and 12, while the side edges of the panels 1 1 and 12 move relative to the profiled side surfaces of the channel 47 without the formation of cracks .
• a kinematic mechanism 42 can be applied, connecting by rods and a rocker rotary leaf and axis 9 of the front adjustable panel 1 1.
• discharge openings 39 are made to equalize the pressure in the channel and in the cavity above the rear adjustable panel 12.
• the cavity above the adjustable panels 1 1, 12 is divided into two halves by a curtain 45, made in the form of a folding partition, and serves to separate air with different pressures that entered the subpanel space through perforations, a transverse drain slot 15 between the adjustable panels and discharge openings 39.
• the shutter 45 is a pivotally connected two flat panels - the upper and lower.
• the upper panel is pivotally mounted on the design of the compartment 46 of the control mechanism of the rear adjustable panel, the lower is pivotally mounted on the rear adjustable panel.
• To ensure the kinematic operability of the curtain 45 its rotation axes 32, 33, 34 are oriented in space in such a way that they have one intersection point 35 lying on the rotation axis 10 of the rear adjustable panel 12.
• the method of regulation of the air intake with swept edges is as follows.
• the adjustable air intake panels 1 1 and 12 are in the maximum throat position (retracted position, main line in the drawings), providing its area at which there are no supersonic flow velocities in the channel.
• the efficiency of an aircraft power plant is related to the efficiency of flow inhibition in the air intake.
• the supersonic flow in the air intake is inhibited in the shock waves 26, 27, 28, which are formed during the flow around the wedges of the braking system.
• the adjustable panels 1 1 and 12 synchronously deviate from the position corresponding to subsonic flight.
• the synchronization of the deflection of the panels 1 1, 12 is ensured by mechanical coupling between the front and rear adjustable panels 1 1, 12 using rods 43.
• the front adjustable panel 11 is simultaneously driven.
• the transverse gap 15 is formed when the position of the adjustable panels 1 1 and 12
• the gap 15 is absent.
• Drainage of the boundary layer is additionally possible through an additional transverse gap located in the throat area on the stationary braking wedge
• An additional transverse gap opens mainly at supersonic flight modes when the position of the adjustable panels 11 and 12 is different from the removed one. With the retracted position of the adjustable panels 1 1 and 12, the aforementioned additional transverse gap is closed by the sash 23.
• the shutter 45 begins to open at the same time, separating the air that enters the cavity above the rear adjustable panel 12 through the discharge openings 39, and the air that enters the cavity above the front adjustable panel And through the perforation and the transverse drain slot 15 between the adjustable panels 1 1 and 12.
• the proposed control method provides high internal gas-dynamic characteristics of the air intake, the configuration of which at the same time helps to reduce its radar signature due to the parallelogram shape of the entrance in the front view and the sweep of all the edges of the entrance and the steps of the braking wedges.
• the choice of orientation of the mentioned elements forming the input, 0 allows you to orient their design in relation to the direction of the radar radiation in such a way as to deviate from this direction the signal reflected from the structure, as well as to exclude the presence of corner reflectors.

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• 2011
  • 2011-04-29 RU RU2011116972/06A patent/RU2460892C1/ru active
• 2012
  • 2012-04-28 CN CN201280032672.XA patent/CN103797229B/zh active Active
  • 2012-04-28 WO PCT/RU2012/000342 patent/WO2012148319A1/ru active Application Filing

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