RU2558525C1 - Method of hypersonic drone active heat protection and aerodynamic drag - Google Patents

Abstract

FIELD: aircraft engineering.

SUBSTANCE: invention relates to active thermal protection of hypersonic drone heat-beat leading edges. Proposed device comprises heat carrier and heat protection ply generation means. Drone nose accommodates cylindrical gas-jet resonator arranged between its leading edge and combustion chamber and provided with the system of control valves located at resonator sidewall. Resonator open inlet is aligned with the drone leading edge and directed toward incident flow. Resonator outer surface supports container with heat carrier composed of methane hydrate and methane hydrate transformer into the mix of steam and methane. The latter is kept under pressure in pulse mode at frequency over 100 Hz with the help of gas-jet resonator to produce protective ply at resonator open inlet to protect the drone leading edge against peak hear loads.

EFFECT: decreased heat loads, higher fuel efficiency.

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Description

The invention relates to aircraft and rocket technology, in particular to active thermal protection of heat-stressed leading edges of a hypersonic unmanned aerial vehicle (UAV).

Analogs of the proposed device are passive means of protecting heat-stressed structural elements of the aircraft using high-temperature coatings (Problems of mechanics and heat transfer in space technology. Edited by Belotserkovsky OM M .: Mechanical Engineering, 1982; US Patent No. 6497390, 12/24/2002; patent RU No. 2383476C1, IPC B64G 1/58, B64G 1/62, 12/25/2008).

A known method of non-destructive thermal protection of the leading edge of the aircraft from exposure to intense heat flux and the leading edge of the aircraft with non-destructive thermal protection (patent RU No. 2149808 C1, IPC B64G 1/58, B64C 1/38, 1/36, 08.06.1999), including a shell with minimal aerodynamic drag and means of transporting energy from the leading edge, perceiving peak thermal loads.

A disadvantage of the known technical solution is the additional aerodynamic drag of a blunt leading edge with a shell at hypersonic flight speeds.

The closest technical solution to the proposed device for active thermal protection and modulation of the aerodynamic drag of a hypersonic UAV is a prototype device that implements a method of thermal protection and modulation of the aerodynamic drag of an object launched from a spacecraft (patent RU No. 2211910 C1, IPC B64G 1/58, S09D 1 / 02, B64C 1/38, 05/31/2002) containing a heat carrier and means for forming a heat-protective layer.

A disadvantage of the known technical solution is the increased power consumption.

The objective of the claimed invention is the creation of effective thermal protection of the heat-stressed front edge of the aircraft and the modulation of its aerodynamic drag in hypersonic flight modes in the atmosphere.

The technical result obtained by carrying out the invention is to reduce peak thermal loads on the structural elements of a hypersonic UAV and increase the fuel efficiency of its power plant.

The solution of the problem and the technical result are achieved by the fact that in the device of active thermal protection and modulation of the aerodynamic resistance of a hypersonic UAV containing a coolant and means for forming a heat-protective layer connected to the UAV control system, inside the nose of the UAV between its front edge and the combustion chamber of the power plant along the axis The UAV has a cylindrical gas-jet resonator with a system of controlled valves located on the side wall of the resonator, the resonance being open of the torus is aligned with the leading edge of the UAV and directed towards the incoming flow, on the outer surface of the resonator on its side walls around the circumference there is a container with a coolant in the form of methane hydrate and a methane hydrate converter into a mixture of water and methane vapors, which, under pressure in a pulsating mode with a frequency of more than 100 Hz, with the help of a system of controlled valves of a gas-jet resonator, it is possible to form a protective layer at the open entrance of the resonator that protects the front edge of the UAV from pi ovyh thermal loads.

A diagram of the device of active thermal protection and modulation of the aerodynamic drag of a hypersonic UAV is shown in Figure 1. In the nose 4 of a hypersonic UAV 1, between its leading edge 2 and the combustion chamber 11 of the power plant 12, a cylindrical gas-jet resonator 7 with a system of controlled valves 6 located on the side wall of the resonator 7, and the open entrance 8 of the resonator 7 is aligned with the front edge 2 of the UAV and is directed towards the oncoming flow. On the outer surface of the resonator 7, a container 3 with a coolant in the form of methane hydrate and a methane hydrate converter 5 into a mixture of water and methane vapors are installed on its side walls around the circumference. In addition, in figure 1 is indicated: 9-UAV control system, 10-fuel.

The device operates as follows.

During the movement of a hypersonic UAV 1 in the atmosphere, an air stream rushes at it at a speed of V ₀ , a head shock wave is formed and the temperature of the deceleration of the flow reaches about 2000K. The structural elements of the aircraft, and primarily on its front edge 2, receives heat flux, which can damage the structure or change the configuration of the front edge 2, which determines the aerodynamic characteristics of the UAV.

In order to cool the UAV leading edge 2 in front of it using a converter 5 through a system of controlled valves 6 located on the side wall of the gas-jet resonator 7, a protective layer is created from the decomposition products of methane hydrate in the form of a mixture of water vapor and methane. The resulting mixture is sent to a gas-jet resonator 7, in which a pair of water and methane under pressure in a pulsating mode with a frequency of more than 100 Hz through the open inlet 8 of the gas-jet resonator is introduced towards the incident flow. As a result, a protective layer is formed, which shields the leading edge of the UAV from peak thermal loads. It was experimentally established that more than 242 kJ is required for the complete dissociation of one mole of water vapor. The dissociation of methane in the presence of water vapor also occurs with intensive energy absorption and a good yield of hydrogen, atomic carbon, acetylene and other components with high enthalpy, which can be effectively used in the combustion of the air-fuel mixture in the combustion chamber 11 of the power plant 12 of a hypersonic UAV 1.

Introducing a mixture of water vapor and methane with a gas-jet resonator 7 towards the incoming flow in a pulsating mode also modulates the aerodynamic drag of the UAV and contributes to the stability of the UAV boundary layer.

Thus, the present invention allows:

- create effective thermal protection of the heat-stressed leading edge of a hypersonic UAV by reducing peak thermal loads on UAV structural elements with the formation of a protective layer;

- to improve the stability of the boundary layer by creating a modulation of the aerodynamic drag of the UAV when injected into the incoming high-speed stream using a gas-jet resonator of water vapor and methane under pressure in a pulsating mode;

- organize the absorption of free flow energy during the dissociation of water molecules, methane, as well as the synthesis of acetylene and other components;

- to increase the fuel efficiency of the UAV and improve its overall dimensions due to the use of the obtained decomposition products of methane hydrate with added enthalpy in the combustion chamber of the power plant of a hypersonic UAV.

Currently, a decision has been made to create a prototype device (technology demonstrator).

Claims (1)

A device for active thermal protection and modulation of the aerodynamic drag of a hypersonic UAV, containing a coolant and means for forming a heat-shielding layer connected to the UAV control system, characterized in that a cylindrical gas-jet resonator with a system is placed inside the UAV nose part between its leading edge and the combustion chamber of the power plant along the UAV axis controlled valves located on the side wall of the resonator, and the open entrance of the resonator is aligned with the leading edge of the UAV and is directed towards I meet the incoming flow, on the outer surface of the resonator on its side walls around the circumference there is a container with a coolant in the form of methane hydrate and a methane hydrate converter into a mixture of water and methane vapors, which, under pressure in a pulsating mode with a frequency of more than 100 Hz, using a system of controlled valves a gas-jet resonator provides the possibility of forming a protective layer at the open entrance of the resonator that protects the leading edge of the UAV from peak thermal loads.