5results about How to "Improve stealth performance" patented technology

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.

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.

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.

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.