38results about How to "Improve infrared stealth performance" patented technology

The invention relates to the design technique of aero-engine nozzles, in particular to a convergent-divergent nozzle with a stealth function, and aims to at least solve the problem of large occupation of a conventional convergent-divergent nozzle. The convergent-divergent nozzle with the stealth function comprises a convergent segment, a divergent segment and a straight tubular transition throat segment, wherein the end surface of a first inlet end of the convergent segment is circular, the end surface of a first outlet end, parallel to the end surface of the first inlet end, is semi-circular, and the centers of the two end surfaces are on the same plane; the end surface of a second inlet end of the divergent segment is semi-circular, the end surface of a second outlet end, parallel to the end surface of the second inlet end, is circular, and the centers of the two end surfaces are on the same plane; and the straight tubular transition throat segment is connected with the first outlet end in a sealing manner through a third inlet end and connected with the second inlet end in a sealing manner through a third outlet end. The convergent-divergent nozzle with the stealth function is simple in structure, light in weight, high in reliability and convenient to mount, manufacture and lose weight, and can enhance the infrared stealth effect and the radar stealth effect without changing the structure of a plane.

The invention provides a pre-evaporation type integrated afterburner. An oil cavity is formed inside an afterburning inner cone, and is connected with a fuel oil channel inside a rectification support plate flame stabilizer. Fuel oil is heated in the oil cavity to become gas or a supercritical body, and then the gas or the supercritical body enters the fuel oil channel inside the rectification support plate flame stabilizer and is sprayed out from direct-injection type spraying nozzle small holes in the two sides. The spraying nozzle small holes are reasonably formed so that the mixing effect of the fuel oil and the gas can be effectively improved, and the burning efficiency is improved. In addition, a large amount of heat is transmitted to the fuel oil through the afterburning inner cone, so that the self temperature is decreased, and the infrared stealth performance is effectively improved. The pre-evaporation type integrated afterburner has the beneficial effects that on the basis of an integrated afterburner structure, by reasonably leading in the structure of the oil cavity inside the afterburning inner cone and the structure of the fuel oil channel inside the rectification support plate flame stabilizer and reasonably forming the direct-injection type spraying nozzle small holes, the burning efficiency is effectively improved, and the infrared stealth performance is effectively improved.

The invention discloses a stealth exhaust pipe provided with an adjustable conical cavity. The exhaust pipe comprises an exhaust system; the exhaust system comprises an outer duct, an inner duct, a supporting plate, a central cone, a spraying pipe wall surface, a telescopic sleeve, the conical cavity and an aerosol injection device; the telescopic sleeve is arranged at the cone vertex of the central cone of the exhaust system and comprises an inner sleeve and an outer sleeve; the inner sleeve penetrates through the conical cavity to communicate with the aerosol injection device arranged insidethe conical cavity; a plurality of aerosol storage devices are arranged inside the conical cavity and communicate with the aerosol injection device; a plurality of aerosol discharging pipelines are connected onto the aerosol injection device; outlets of the aerosol discharging pipelines are arranged on the outer surface of the conical cavity; and an air pump is arranged inside the aerosol injection device. According to the exhaust pipe, the stealth requirement of an aircraft for the exhaust pipe is considered, and meanwhile, the problems that wave absorbing media are prone to loss and fallingdue to coating of high-temperature wall surfaces and the thrust loss is relatively high due to exhaust pipes adopting S-bend structures are avoided.

The invention discloses a throat offset type pneumatic vectoring exhaust nozzle with saw-tooth-shaped solid tabs at an outlet. The throat offset type pneumatic vectoring exhaust nozzle comprises an exhaust nozzle body, wherein a flow channel in the exhaust nozzle sequentially comprises an exhaust nozzle inlet, an isometric section, a first throat front part convergent section, a first throat, a second throat front part expanding section, a second throat front part convergent section and a second throat; and the saw-tooth-shaped solid tabs are arranged on upper and lower wall surfaces at the downstream of the second throat front part convergent section and a projection area of the outlet of the exhaust nozzle is not changed. According to the throat offset type pneumatic vectoring exhaust nozzle disclosed by the invention, the saw-tooth-shaped solid tabs which are inclined toward are arranged at upper and lower sides of the outlet; and an infrared stealth function of the exhaust nozzle is improved under the condition that the projection area of the outlet is equal to an original projection area. Compared with a standard throat offset type pneumatic vectoring exhaust nozzle with a rectangular outlet section, the exhaust nozzle provided by the invention can be used for effectively reducing the speed of a flow spraying central line and reducing the length of a core region and noisesthrough reinforcing flow spraying and blending of the outlet; and meanwhile, the exhausting temperature is reduced and the infrared stealth function is improved.

This application relates to the field of aero-engines. It is a binary nozzle structure for ejecting cold air from the engine compartment, including a circular turning square section, a converging section and an expanding section connected in sequence. There is a cooling channel, the outside of the convergent section and the expansion section is provided with an outer cover, and the two sides of the convergence section and the expansion section protrude up and down respectively to form a side wall structure, and the upper and lower sides of the side wall structure are provided with The first ventilation hole, the fourth cooling passage communicated with the first ventilation hole is opened in the side wall structure, and the inlet end of the fourth cooling passage communicates with the cooling passage in the circular section, the cooling in the engine compartment The device can enter into the first vent hole. It has the technical effect of improving the cooling performance of the nozzle and reducing infrared radiation.

The invention discloses a design method of an elliptical throat offset type aerodynamic vectoring nozzle. The inner flow path of the elliptical throat offset type aerodynamic vectoring nozzle includes nozzle inlets, equal straight sections, Convergent section at the front of the first throat, first throat, expansion section at the front of the second throat, convergent section at the front of the second throat, and second throat; by designing the shape of the flow section of each section as an ellipse, the flow of the inner runner is changed. Field structure, so it can provide omnidirectional vector angle and ensure high-efficiency vector thrust performance, and has a good mixing effect of internal and external flow, effectively improving the infrared stealth performance of the nozzle, thus solving the problem of strong stealth performance of modern aircraft and high maneuverability; in addition, the unique flat shape of the elliptical throat offset aerodynamic vector nozzle is more suitable for some aircraft with special shapes such as flying wing layout, and can also meet the aerodynamic-stealth integrated layout of future aircraft requirements, a wide range of uses.

The invention relates to an exhaust system applied to an air vehicle, in particular to a stealth exhaust system. A cross-section shape of a throat of a spray pipe is designed to a non-round shape with an aspect ratio greater than 1, so that mixing of high-temperature exhaust airflow of an engine and ambient air is strengthened, the exhaust temperature is reduced, and an infrared stealth property of the exhaust system is improved. Central lines of the stealth exhaust system are three longitudinal S-bent curves, and the bent central lines can enable sidewalls of the spray pipe to shield high-temperature components of the engine, therefore, the infrared stealth property of the exhaust system can be improved; and simultaneously, the bent central lines can also cause radar waves going into the stealth exhaust system from the rear to difficultly generate backward waves, therefore, a radar stealth property of the exhaust system can be improved. Properties of the exhaust system are considered while the stealth properties are ensured, so that a requirement of the stealth exhaust system on the layout space is reduced, and adaptability of the stealth exhaust system is strengthened.

The invention relates to a preparation method of an organic-inorganic composite infrared stealthy material. The preparation method comprises the following steps: firstly preparing alumium-doped zinc oxide by virtue of a sol-gel method, and then covering the alumium-doped zinc oxide with a layer of conductive polymer by virtue of in-situ chemical oxidative polymerization. The excellent infrared stealth property of the alumium-doped zinc oxide is organically combined with unique infrared absorption and reflection properties of the conductive polymer, and consequently, the obtained material is wide in infrared absorption band and good in infrared stealth effect.

The invention discloses a mechanically adjustable S-bend nozzle nozzle structure, belonging to the field of aero-engines; it includes an S-bend section and 8 adjustment pieces, and the 8 adjustment pieces are hinged in the circumferential direction to form an annular structure; the annular structure is hinged to the S-bend. The inner wall of the rectangular outlet of the curved section constitutes a sealed air flow channel; the 8 regulating pieces are an upper regulating piece, a lower regulating piece, two side regulating pieces, two upper regulating pieces, and two lower regulating pieces; Each side regulating piece is hinged on the short sides of the rectangular outlet of the S-bend segment; the upper regulating piece and the lower regulating piece are respectively hinged on the long sides of the two sides of the rectangular outlet of the S-curve segment; the two upper regulating pieces are hinged on the between the two side adjustment pieces and the upper adjustment piece; the two lower side adjustment pieces are hinged between the two side adjustment pieces and the lower adjustment piece respectively. The invention can enhance the infrared stealth performance of the nozzle through the shielding of the high-temperature engine components by the S-bend section, and compared with the conventional axisymmetric nozzle, the infrared radiation intensity can be reduced by more than 70%.