RU2740739C2 - Detonation jet engine - Google Patents

Abstract

FIELD: astronautics.

SUBSTANCE: invention relates to rocket engineering using solid-propellant fuel for various purposes and is intended primarily for systems for orientation of spacecraft in orbit. Light-erosion rocket engine includes housing with movable and controlled surface and supersonic nozzle, translucent cylindrical shell filled with inert gas, with electrodes located on opposite ends of translucent shell and connected to high-voltage discharge capacitor through pulse circuit breaker. Moving surface is made in form of solid light-absorbing material, for example, ebonite. Between body and surface there is a translucent cylinder with a nozzle forming a channel. Housing is equipped with a reflector, and the translucent cover is made in the form of a spiral and is located inside the housing.

EFFECT: simplified and longer engine life.

1 cl, 1 dwg

Description

The invention relates to rocket technology using solid propellants for various purposes and is intended primarily for attitude control systems of spacecraft in orbit

Known pulse electric discharge motors [1-3] containing combustion chambers and a nozzle with a charge of solid fuel and electrodes connected to discharge capacitors. However, in such engines, after each discharge, the conditions for the subsequent electrical impulse change. In other words, the conditions for the realization of an electric discharge are not constant.

Known rocket engine [4], containing a combustion chamber, a nozzle with a recessed part, a solid fuel charge, consisting of two parts, one of which has a reduced oxidant content and is located close enough to the recessed entrance to create a boundary layer of combustion products with an oxidant deficiency passing through the annular gap and flowing around the tapering part and the throat area, thereby reducing the entrainment of the said tapering part and the throat section. Two schemes of charges are considered: with a central channel and end combustion. However, such a rocket engine is based on the combustion of solid fuel, and the investigator, the combustion temperature cannot exceed 4-5 thousand Kelvin.

As an analogue, an electric-discharge [5] jet engine was selected, containing an accelerating section in the form of a hollow tube - a cathode, and a pointed anode, separated by a dielectric and connected to a high-voltage voltage source and equipped with a working fluid supply system. However, this engine is only able to partially use the working fluid.

As an analogue, a pulsed electric-discharge jet engine [6] was selected, containing a section in the form of a gas-dynamic resonator with a hollow accelerating tube, ending with a supersonic nozzle, an anode and a cathode, separated by a dielectric and connected to a high-voltage voltage source and a high-voltage capacitor, equipped with a system for supplying and igniting the working fluid ...

However, the working fluid supply system contains a working fluid supply dispenser; the system that initiates a detonation discharge is rather complicated due to the fact that the discharge is carried out in unstable conditions, since the use of a gaseous working fluid does not always allow it to be uniformly placed in the resonator.

As a prototype, a pulsed rocket engine was chosen [7] The peculiarity of this pulsed rocket engine is that the feed and ignition system is made in the form of a transparent dielectric tube filled with an inert gas, at the ends of which the anode and cathode are installed, and the working fluid is made in the form of a cylindrical a truncated cone made of light-absorbing material, with its wide base facing the supersonic nozzle, and a dielectric transparent tube installed along the axis of symmetry of the cylindrical truncated cone.

The disadvantages of such a pulsed rocket engine include the fact that the body itself is made of light-absorbing material. This leads to the fact that over time, after several tens of thousands of pulses of light, the body becomes thinner and after another pulse increase in pressure, it can be mechanically destroyed. It is difficult to replace such a housing due to its complex shape. The simplest warrant is to make such a housing from any hard metal equipped with a reflector. The resource of such a body is unlimited from the number of light pulses. The light-absorbing material made in the form of a cylinder can be easily interchanged by feeding through holes inside the end of the housing. The disadvantages include the fact that in the prototype the light source is made in the form of a transparent dielectric tube, which limits the distance between the anode and the cathode. This distance can be increased only by making it in the form of a spiral and positioning it inside the body.

The newly proposed light erosion rocket engine comprising a housing with a movable and controllable surface and a supersonic nozzle, a translucent cylindrical shell filled with an inert gas, with electrodes located at opposite ends of the translucent shell and connected to a high-voltage discharge source and a high-voltage capacitor.

A feature of the proposed light-erosion rocket engine is that the movable surface is made in the form of a solid light-absorbing material, for example, ebonite, equipped with a reflector, and the translucent shell is made in the form of a spiral and is located inside the body.

FIG. 1 depicts a proposed light erosion rocket engine. It contains a supply and ignition system made in the form of a transparent dielectric tube 1 filled with an inert gas 2, at the ends of which anode 3 and a cathode 4 are installed, connected to a high-voltage voltage source 5 and a high-voltage capacitor 6, and the working fluid is made of light-absorbing material 7 made in the form of a body and a supersonic nozzle 8.

The features of the proposed light-erosion engine include the fact that the movable surface is made of a solid light-absorbing material 7, for example, ebonite or graphite, a translucent cylinder 9 is located between the body and the surface, with a nozzle 8 forming a channel 10, the body is equipped with a reflector 11, and the translucent dielectric tube 1 is made in the form of a spiral and is located inside the body.

The proposed light erosion rocket engine works as follows. When energy enters from a high-voltage source 5 and a high-voltage capacitor 6, it is supplied to electrodes 3 and 4. A low-temperature plasma with a brightness temperature of more than 25,000 K appears between electrodes 3 and 4, which is difficult to achieve for any chemical combustion. The luminous flux easily penetrates through the translucent dielectric tube 1, the transparent cylinder 9, and being repeatedly reflected from the reflector 11 eventually hits the light-absorbing surface 7. The coefficient of conversion of electrical energy into light, thanks to the inert gas, reaches 70-80 percent. The heating temperature of the surface 7 can be estimated in accordance with the formula:

where α is the absorption coefficient,

,I - radiation intensity

,

t - time [s],

С - heat capacity,

ρ is the density,

- температуропроводность,

- thermal diffusivity,

λ - thermal conductivity.

Tube 1 800 mm long, wound into a spiral, withstands thousands of pulses with a discharge energy of 10,000 J, with a response time of the order of 10 ^-3 seconds. The developed capacity can be estimated at 10 MW. The products of light erosion at a supersonic speed flow out through the supersonic nozzle 8. The process is accompanied by a powerful sound pulse and on the paper near the nozzle 8 the products of erosion form shock interference fringes. As the surface 7 is triggered, it is fed from the receiving hopper (not shown in the figure)

Information sources

1. Grishin S.D., Leskov L.V., Kozlov N.P. Electric rocket motors. M .: Mechanical Engineering, 1975 p. 198 ... 223.

2. Favorskiy ON, Fishgoit VV, Litovskiy EI Fundamentals of the theory of space electric propulsion systems. M .: Mechanical engineering, Higher school, 1978, p. 170 ... 173.

3. Space engines - state and prospects. Edited by L. Keivney (translated from English under the editorship of A. S. Koroteev). M .:, 1988 p. 186 ... 193.

4 US patent No. 6226979.

5. Patent RU No. 200710731 - Pulse electric jet engine.

6. Patent RU No. 2433293 - Impulse detonation jet engine.

7. Prototype - RF Patent No. 2644798 for a pulse detonation engine.

Claims (1)

A light erosion rocket engine containing a housing with a movable and controllable surface and a supersonic nozzle, a translucent cylindrical shell filled with an inert gas, with electrodes located at opposite ends of the translucent shell and connected to a high-voltage discharge capacitor through a pulse breaker, characterized in that the movable surface is made in in the form of a solid light-absorbing material, for example ebonite, between the body and the surface there is a translucent cylinder with a nozzle forming a channel, the body is equipped with a reflector, and the translucent shell is made in the form of a spiral and is located inside the body.

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