14results about How to "Improve stealth performance" patented technology

The utility model belongs to the technical field of ships, and discloses a base, a ceiling lamp and a ship. The base is installed in an installation hole of a cabin roof structure of a ship, and the two opposite sides of the cabin roof structure are the invisible installation side and the illumination side respectively. The base comprises a base bottom structure, a liner structure, a transition structure and a ceiling lamp base structure. The gasket structure is of an annular structure and is connected to the invisible installation side, and the base bottom structure is connected to the gasket structure. The transition structure is located in the mounting hole, connected to the base bottom structure and extends towards the lighting side. The ceiling lamp base structure is connected to the side, away from the base bottom structure, of the transition structure. According to the base, the thickness of the bulged part of the ceiling lamp relative to the ceiling structure can be reduced, and the hiding effect of the ceiling lamp is improved.

This invention discloses an integrated S-curve nozzle design method and nozzle for aircraft with a blended wing-body layout, belonging to the field of aero-engines. The method comprises the following steps: obtaining the external surface of the blended wing-body aircraft and the position and size parameters of the engine exit; establishing a model of the S-curve section of the nozzle; obtaining and modifying the upper expansion surface at the nozzle exit; designing the centerline of the nozzle's aft deck using Lee curves; designing the double sidewalls of the nozzle's aft deck using Lee curves; obtaining the aft deck profile of the nozzle based on the centerline and double sidewalls determined in steps 3 and 4; and obtaining the sidewall profile of the nozzle exit. This invention solves the problems of limited space layout, large drop between the nozzle exit and the aircraft's tail edge, and maintaining the streamline of the aircraft's external surface after nozzle installation when designing an integrated S-curve nozzle in a blended wing-body layout.

The embodiment of the present disclosure discloses a flexible combined multifunctional broadband metasurface antenna for synthetic aperture radar, which comprises, from inside to outside, a core metasurface antenna located at the center and a peripheral metasurface located at the periphery, and the core metasurface antenna and the peripheral metasurface are connected through a U-shaped slot plug structure, wherein the core metasurface antenna and the peripheral metasurface can be replaced according to different application scenarios. The present disclosure has the characteristics of simple and reliable modular structure and flexible configuration according to task requirements; it meets the requirements of high-precision multiple transmission modes and corresponding amplitude-phase consistent multiple polarization reception of synthetic aperture radar, effectively increases the working bandwidth of the core antenna under low profile, reduces the radar scattering area of the antenna, optimizes the antenna radiation pattern and reduces the mutual coupling characteristics, further improves the imaging performance of the synthetic aperture radar, and reduces the signal-to-interference ratio of the synthetic aperture radar system.

The application discloses a rear body contraction type fluid thrust vector nozzle, which comprises a contraction section, a static pressure cavity, a main jet outlet, a control valve, a contraction wall surface, a secondary flow inlet and a wall surface secondary flow hole. The contraction section is arranged above and below the static pressure cavity, the main jet outlet is arranged at the tail end of the contraction section, the contraction wall surface is arranged at the tail of the static pressure cavity, the secondary flow inlet is arranged on the side of the rear body contraction type fluid thrust vector nozzle, and the wall surface secondary flow hole is arranged on the contraction wall surface. The static pressure cavity is in communication with the secondary flow inlet and the wall surface secondary flow hole, and the secondary flow inlet is controlled by the control valve. The rear body contraction type fluid thrust vector nozzle can realize jet vector deflection control while reducing the thickness of the rear body, has a good application prospect in the integration design of the fluid thrust vector and an aircraft, and can further promote the practical application of the fluid thrust vector nozzle.

This invention belongs to the field of metamaterials technology, specifically relating to an adjustable integrated absorption and reflection metamaterial structure. It includes several basic units arranged in a periodic array. Each basic unit comprises a resonant unit, a dielectric layer, and a reflector layer stacked sequentially. The dielectric layer is deformable to create a cavity between itself and the reflector layer or to fit tightly against it. The resonant unit includes four sequentially connected arc-shaped segments arranged centrally symmetrically. The ends of adjacent arc-shaped segments connect to form sharp corners extending towards the center of the resonant unit, with a gap between opposing sharp corners. This invention offers good reconfigurability, high flexibility, and deformability, allowing for easy adjustment of the state and switching of operating modes according to actual usage needs, achieving broadband absorption or complete reflection functions from 4.9 GHz to 16.3 GHz.

The utility model provides a kind of integrated stealth water column antenna, through the integration design of shell, water pump assembly, ground net plate and signal transmission component, significantly reduce antenna volume and promote stealth performance, shell columnar structure inlaying injection channel and isolation magnetic ring, realize the physical isolation of radio frequency signal and seawater, avoid the radar scattering problem caused by exposed metal parts of traditional shipborne antenna;Water pump assembly is directly connected with the lower side of shell, and forms radiator by injecting seawater, and after communication, pump can be stopped to realize antenna invisibility, signal transmission component and ground net plate are horizontally arranged on the upper end surface of shell, form compact plane layout, ground net plate arranged on the upper end surface of shell floats in sea level during use, only makes nozzle part above sea level, greatly enhances stealth performance, avoids the technical problem that water column antenna in the prior art is only applicable to ship platform use, use scene has great limitation, cannot meet the stealth demand.

The application belongs to the technical field of skin materials, and particularly relates to an X-waveband stealth skin, a preparation method and application thereof. The preparation method of the X-waveband stealth skin comprises the following steps: (1) preparing a modified epoxy resin system; (2) laying a carbon fiber mixture to obtain a carbon fiber mixture film layer; (3) laying a conductive mixture on the surface of the carbon fiber mixture film layer to obtain a conductive mixture film layer; (4) laying a wave-absorbing mixture on the surface of the conductive mixture film layer to obtain a wave-absorbing mixture film layer; (5) laying a wave-transmitting mixture on the surface of the wave-absorbing mixture film layer to obtain a skin material; and (6) vacuumizing and heating and curing the skin material to obtain an X-waveband stealth lightning-proof skin. The X-waveband stealth skin has excellent stealth performance and lightning-proof capability, and has a higher mechanical performance retention rate in an ultralow-temperature environment.

This invention discloses a ship's bridge roof structure, comprising: a sealing plate, a reinforcing web, and a wiper mounting base. The sealing plate is integral, with both edges connected to the hull plating, providing a smooth transition and completely covering the upper area of ​​the bridge window. The reinforcing web connects the sealing plate to the hull plating, and the wiper mounting base extends from it. The wiper mounting base consists of a panel and an elbow plate, allowing for the installation of wipers. This invention completely conceals the wiper mounting area along the upper edge of the bridge window with an integral sealing plate, effectively improving the ship's stealth capabilities without compromising its overall aesthetic appearance. Secondly, it completely protects the wipers from direct impact by seawater and storms, significantly reducing equipment failure rates. Finally, it changes the conventional front-mounted wiper installation to a top-down installation between the sealing plate and the hull plating, allowing workers to operate from the upper deck, ensuring safety and reliability, and enabling rapid wiper installation and removal, greatly improving maintainability.

The utility model belongs to the technical field of full-automatic ship equipment, and provides a stealth protection device for ship equipment. Comprising a ventilation device, a door stopper, a door, a sealing device, a protection device body and a cover plate. Three doors capable of being opened are arranged on the protection device body, and the doors can be closed and opened by rotating the hinges. A door stopper is arranged on the protection device body and used for fixing an opened door. Two detachable doors are arranged on the lateral front portion of the protection device body, and a cover plate is arranged below the front portion of the protection device body. A ventilation device is arranged above the rear part of the protection device body, and a sealing device is arranged in front. A carbon fiber composite interlayer is arranged in a shell of the protection device body, the inner surface or the outer surface of the protection device body is coated with a stealth coating, and the outer surface of the protection device body is coated with corrosion-resistant paint. By adopting the polyhedral appearance reflection principle and utilizing the wave absorbing effect of the carbon fiber composite interlayer and the wave absorbing effect of the stealth coating, the protection device is smooth and simple in appearance, light in weight and good in stealth effect, and the requirements of equipment stealth and adaptability are met.

The invention discloses a large-size frequency selective surface invisible antenna housing and a preparation method thereof. The antenna housing comprises an outer skin layer, a frequency selective surface layer, a sandwich layer and an inner skin layer which are sequentially stacked from outside to inside. The preparation method comprises the following steps: splicing the frequency selective surface layer by adopting small-size diaphragms, filling butt joint gaps with conductive slurry, and curing to realize electric connection to form a complete surface. The method has the advantages that: 1, the production cost is less than 10% of that of a laser etching method; and 2, large-size products are manufactured by slicing and then splicing. And 3, the process is controllable. And 4, the stealth performance is excellent.

This invention discloses an air conditioning control method, device, electronic device, and storage medium. The method includes: in harsh environments, controlling the air conditioner to operate according to a preset operating strategy corresponding to the preset level; for air conditioners whose preset level requires normal operation even in harsh environments, controlling them to maintain normal operation; for air conditioners whose preset level allows for low-energy operation in harsh environments, adjusting the air conditioner's operating parameters according to adjustment rules that improve the air conditioner's stealth and / or shock resistance; and for air conditioners whose preset level requires forced shutdown in harsh environments, controlling them to be forcibly shut down. This method can solve the technical problem in related technologies where air conditioning control methods cannot coordinate comfort and safety in harsh environments.

The invention relates to the technical field of fastening connection of aerospace, and particularly discloses a high-shear-resistance slotless titanium alloy threaded self-plugging rivet and a preparation process thereof.The self-plugging rivet comprises a core rod, a pipe body, a rivet body and a driving nut, the driving nut, the rivet body and the pipe body are sequentially arranged on the core rod in a sleeving mode, and the rivet body is divided into a head part, a middle part and a tail part; the end face of the end, close to the driving nut, of the nail body head is flat, the driving nut abuts against the end face, a threaded groove allowing the core rod to penetrate through is formed in the center of the end face, the surface roughness of the end face is 1.6-2.2 micrometers, and the diameter of the outer circle of the end face is larger than that of the circumcircle of the driving nut. The end face of the head of the rivet body is flat, the center of the end face is only provided with the threaded groove allowing the core rod to penetrate through, after the core rod is broken, the core rod can completely shield the threaded groove in the center of the end face, and the structure can reduce the radar reflection area and improve the stealth performance of an airplane.

This utility model discloses a flush-fitting, concealed fire door, including a door frame. Both sides of the door frame are hinged to door panels via concealed hinges, and the surface of each door panel has a mounting groove. This utility model employs a flush-fitting frame and door panel design, using concealed hinges to connect the door frame and door panel, ensuring that the front of the door frame and the front of the door panel are on the same plane, parallel to the wall. This allows it to seamlessly integrate into the overall decoration style of modern buildings, avoiding the visual abruptness caused by uneven frame and door panel openings in traditional fire doors. This significantly enhances the aesthetics of the building's interior space and achieves an excellent concealed effect. By setting mounting grooves on the door panel surface and fixing fire-resistant sealing strips within the grooves, the sealing performance of the device is effectively improved. Multiple insulation layers work together to greatly enhance the heat insulation performance of the device. This device possesses the advantages of being aesthetically pleasing, having a good concealed effect, excellent sealing performance, and good heat insulation performance.

This invention provides an embedded air intake structure, relating to the field of flight equipment. It includes an air intake body with a bottom wall and an air inlet. The bottom wall of the air intake body is fixedly connected to the trailing edge of an aircraft wing. The upper surface of the bottom wall of the air intake body is streamlined, allowing for a smooth transition with the upper surface of the wing. The opening of the air intake body near the wing end serves as the air inlet. When the aircraft is in horizontal flight, the air inlet is located above the bottom wall of the air intake body and below the highest point of the upper surface of the wing. This invention also provides an aircraft, including a wing, a fuselage, and the aforementioned embedded air intake structure. The bottom wall of the air intake body is fixedly connected to the trailing edge of the wing, and the wing is fixedly connected to the fuselage. The embedded air intake structure and aircraft provided by this invention can improve air intake efficiency, reduce strong radar echoes, and improve radar stealth performance.