RU2794391C1 - Pulsed laser rocket engine for low-mass orbital spacecraft orientation, stabilization and correction systems - Google Patents

Abstract

FIELD: spacecraft; spacecraft control devices.

SUBSTANCE: invention is designed in particular for orientation and stabilization of vehicles in space. Pulsed laser rocket engine for systems of orientation, stabilization and correction of low-mass orbital spacecraft contains a laser radiation source that generates laser pulses, a focusing lens, a preliminary chamber, a tank for storing a working fluid under pressure, an electrovalve that regulates the flow of a working fluid into the preliminary chamber, a channel of arbitrary section connecting the tank with the solenoid valve, the cylindrical chamber and the rear wall of the cylindrical chamber. The cylindrical chamber is located perpendicular to the pre-chamber. The focusing lens is located at an angle to the preliminary chamber for focusing the laser pulse on the back wall of the cylindrical chamber.

EFFECT: specific impulse of the laser rocket engine is increased.

1 cl, 1 dwg

Description

The invention relates to spacecraft and their control devices, in particular, for orientation and stabilization of vehicles in space.

Known device "Motor system orientation and stabilization of spacecraft" (RF patent No. 2281890, IPC B64G 1/34 (2006.01), published 20.08.2006). The device consists of a housing, a working fluid in the form of a substance that sublimates when heated, electric heaters and refrigerators. The device contains a sealed housing, inside which the working fluid and electric heaters are placed, and refrigerators are located at the ends of the housing. The device works as follows: when the electric heater is turned on, the working fluid is heated, it passes into a gaseous state and is distributed inside the sealed housing. Turning on the refrigerator at the opposite end of the housing creates a larger temperature gradient along the length of the housing, while the working fluid will condense mainly on the cold part of the housing, creating a greater torque. If it is necessary to change the direction of the moment of forces, then it is necessary to turn on the opposite pair of electric heater - refrigerator. With this engine design, the electric heater-refrigerator system is switched on and off in pairs.

The disadvantage of this solution is the increased energy consumption of the engine due to the use of a heater and a refrigerator, which affects the dimensions and weight of the engine, as well as the low reliability of the engine due to the fulfillment of the conditions for ensuring the tightness of the housing for the implementation of the working process.

Known technical solution "LASER-ABLATIVE THRUSTER MICROLAS", given in the publication Overview of Laser Ablation Micropropulsion Research Activities at DLR Stuttgart (Hans-Albert Eckel, Stefan Scharring, Stephanie Karg, Christian Illg, and Johannes Peter, International High Power Laser Ablation and Beamed Energy Propulsion Symposium (HPLA/BEP (2014), April 21-25, 2014 (https://core.ac.uk/download/pdf/31010835.pdf). The device consists of a pulsed laser, an electro-optical zoom lens, an electro-optical device for planar longitudinal control of a laser beam, f-theta lenses with a fixed focal length, a flat reflector (mirror) and a metal target.The device works as follows: a pulsed laser beam passes through an electro-optical lens and enters an electro-optical device, from where it exits through f-theta The disadvantage of this solution is the difficulty of pointing and obtaining a laser spot of the required size due to the presence of a reflecting mirror, as well as the size of the device, which makes it difficult to use in stabilization and orientation systems for small spacecraft.

An f-theta lens is a lens that allows you to focus a laser beam at a given (focal) distance.

The closest in technical essence is the device "Laser-plasma micromotor" (RF patent No. 139344, IPC F02K 1/00 (2006.01), published 04/20/2014). The device consists of a laser radiation source, a system for introducing radiation into an optical fiber, an optical fiber, a mechanism for feeding the optical fiber into the nozzle chamber, a vacuum seal, a nozzle chamber, and a paraxial tube of the optical fiber end holder. The device operates as follows: laser radiation from the source is fed through the radiation input system into the optical fiber, where, interacting at the output of the optical fiber with the radiation-absorbing end, it initiates an optical breakdown of the material of the output end of the optical fiber as a working fluid in the nozzle chamber with the formation of a paraxial gas-plasma jet, providing the transfer to the walls of the nozzle chamber of the oppositely directed recoil reactive impulse. To ensure a quasi-continuous operation of the engine, the generation of laser radiation pulses is consistent with the speed of the mechanism for feeding the light guide into the nozzle chamber to restore the initial position of the radiation-absorbing end of the light guide above the cut of the paraxial tube of the light guide end holder.

The disadvantage of this solution is the complexity of the design, which consists in the presence of a vacuum seal, the complexity of the practical implementation of the device due to the high requirements for the material of the end of the fiber, which must absorb the energy of the laser radiation source, another significant disadvantage is the wear of the end due to the evaporation of the material, as well as the complexity use in low-mass spacecraft orientation engines due to the fact that the working process proceeds under the condition of organizing a quasi-continuous mode of laser pulses supply.

The technical problem of the invention is the creation of a pulsed laser rocket engine for orientation and stabilization of orbital spacecraft with low mass

The technical result is to increase the specific impulse of the laser rocket engine for orientation, stabilization and correction of low-mass orbital spacecraft, reduce the consumption of the working fluid, reduce the weight and size characteristics and simplify the conditions for placement on board a small spacecraft.

The technical result is achieved by additionally containing a focusing lens, a preliminary chamber, a tank, an electrovalve, a channel of arbitrary section, a cylindrical chamber and a rear wall of the cylindrical chamber; the cylindrical chamber is located perpendicular to the pre-chamber.

The proposed device consists of a source of laser radiation (1), which creates laser pulses, a focusing lens (2), through which laser pulses pass and are focused on the rear wall of the cylindrical chamber (8), where pulsed near-surface optical discharges occur and which is located at an angle to the preliminary chamber (3). The working fluid is stored in the tank (5) under pressure, which, through a channel of arbitrary section (7), enters the electrovalve (4), which regulates the flow of the working fluid into the preliminary chamber (3). The working fluid from the pre-chamber (3) due to high pressure tends to the environment through the cylindrical chamber (6), creating an area inside the cylindrical chamber (6) filled with the working fluid. At the moment of occurrence of a pulsed optical near-surface discharge in this area, the internal energy of the working fluid increases and the temperature rises, as a result of which the working fluid accelerates and flies out of the cylindrical chamber (6), creating a thrust impulse of the order of several tens of microns to stabilize the orbital spacecraft with a low mass . Created by a laser source and focused by a lens on the back wall of a cylindrical chamber, a pulsed surface optical discharge has a high temperature (at the discharge point, the temperature reaches several hundred thousand degrees and quickly decreases to tens of thousands at the discharge boundary with the environment). When a pulsed near-surface optical discharge occurs on the rear wall of the cylindrical chamber, the working fluid is heated to high temperatures. Due to this, the gas acquires a high temperature and the internal energy increases, as a result of which a high outflow rate from the cylindrical chamber is achieved, and the outflow rate is estimated by the specific impulse parameter. Thus, it is possible to use a small amount of the working fluid due to the pulsed near-surface optical discharge. The advantage of a pulsed near-surface optical discharge lies in the possibility of creating a discharge under low pressure conditions, when a high power density (of the order of 10 ¹² W/ ^cm pulsed near-surface optical discharge. The reduction in weight and size characteristics is achieved through the use of a compact laser (mass 1 kg, size 25 cm x 15 cm x 15 cm), capable of providing a pulsed laser source.

A pulsed laser rocket engine for low-mass orbital spacecraft orientation, stabilization, and correction systems is shown in FIG. 1.

Implementation example

The working fluid (air) is stored in a pressure tank of 13.61 MPa. When the solenoid valve is open, air from the tank through the pipeline enters the preliminary chamber. The LQ529B laser light source with an energy of 0.35 J, a pulse duration of 10 ns and a wavelength of 1064 nm creates a laser pulse passing through a focusing lens with a focal length of 7 cm and forms a pulsed optical near-surface discharge on the surface of a cylindrical chamber made of aluminum. At the moment air enters the cylindrical chamber, a pulsed optical near-surface discharge occurs, as a result of which the air acquires a temperature of up to 900,000 K and flies out of the cylindrical chamber 3 mm in diameter and 12 mm long, creating a thrust impulse of 17 μNs.

Claims (1)

Pulsed laser rocket engine for systems of orientation, stabilization and correction of orbital spacecraft with low mass, consisting of a source of laser radiation that creates laser pulses, characterized in that it additionally contains a focusing lens, a preliminary chamber, a tank for storing a working fluid under pressure, an electrovalve , regulating the flow of the working fluid into the preliminary chamber, a channel of arbitrary section connecting the tank with the electrovalve, the cylindrical chamber and the rear wall of the cylindrical chamber, the cylindrical chamber is located perpendicular to the preliminary chamber, while the focusing lens is located at an angle to the preliminary chamber for focusing the laser pulse on the rear wall of the cylindrical chamber.

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