RU2511877C2 - Fluid-gas jet engine - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to aerospace engineering and may be used in clustered rocket bodies as a correction engine. Proposed engine comprises tank filled with working fluid and having the bore in cover, chamber and jet nozzle. Working fluid phase splitter is arranged inside the engine chamber, at tank outlet. Control valve with spring and electromagnet is arranged downstream of said splitter. This engine incorporates the device to heat working fluid in area adjoining the tank outlet. Fluid-gas engine generates jet thrust by outflow of water steam formed at gas vaporisation from liquid phase.

EFFECT: thrust adjustment, lower power consumption, non-polluting working fluid.

2 cl, 1 dwg

Description

The present invention is intended for use in rocket and space technology as a corrective propulsion system (KDU) of a spacecraft (SC).

Known liquid jet engine with additional electromagnetic acceleration of the working fluid containing a source of electrical energy, an annular combustion chamber, a mixing head, a disk nozzle and an energy storage device with a switching device (Patent of the Russian Federation No. 2374481 for IPC: F02K99 / 00, 2008). This engine has such disadvantages as a relatively high traction price, the presence of two tanks for storing fuel and an oxidizer. For the normal operation of such an engine, a metered supply of components is necessary.

Known liquid-gas jet engine (GGRD), containing a tank filled with a liquid working fluid, with an outlet in the lid, a chamber and a jet nozzle, after the outlet is installed a capillary tube, behind which is the engine cavity, from which the working fluid enters the nozzle ( Issues of Electromechanics. V. 109. 2009. V. Khodnenko, A. Khromov (FSUE NPP VNIIEM) Corrective propulsion systems for a small spacecraft.). This engine is selected as a prototype. Hydrazine is used as the fuel of this engine.

This engine has a lower traction price, one tank with a liquid working fluid. But this engine has a number of other disadvantages - the inability to regulate engine thrust over a wide range due to the characteristics of the fuel used, the relatively high energy consumption due to the need to heat the engine cavity to carry out a thermocatalytic reaction, and there is also a drawback such as the toxicity of the fuel used.

The technical result of the claimed invention is to obtain the ability to control engine thrust in a wide range, reducing engine power consumption and the use of environmentally friendly working fluid.

The technical result is achieved by the fact that in the liquid-gas jet engine containing a tank filled with a liquid working fluid, with an outlet in the lid, a chamber and a jet nozzle, according to the invention, a control valve with an electromagnet and a spring installed in the chamber at the outlet of the tank after phase separator of the working fluid, and water is used as the working fluid.

At the same time, it is proposed to equip the working chamber with a device for heating the area adjacent to the outlet of the tank.

In the proposed technical solution to create traction, the phenomenon of vaporization is used, and not the thermocatalytic reaction, as in the prototype.

The drawing shows an example of a specific implementation of the claimed jet engine.

A liquid-gas jet engine consists of a tank 1, a control valve 2 with an electromagnet 3 and a spring 4 installed in the chamber 5 at the outlet of the tank 1 after the phase separator 6 of the working fluid, and a nozzle 7 installed after the chamber 5 and the valve body 8.

The essence of the engine is that the working fluid from the tank 1 evaporates and, passing through the capillaries of the phase separator 6, enters the chamber 5, from where, in the case of a signal to the electromagnet 3, the steam passes through the valve 2 through the channels 2 into the nozzle 7 . In the absence of a signal on electromagnet 3, spring 4 provides valve preload (automatic engine shutdown). Since the pressure in the area in front of the nozzle exceeds the pressure overboard, a jet thrust occurs. The engine can work until all the liquid in the tank 1 has evaporated. Thanks to the valve, the engine is regulated until it is completely turned off with the possibility of repeated starts. The advantages of this engine are its low power consumption, non-toxic fuel, non-explosive, regulation in a wide range. In the case of crystallization of the working fluid, the specific impulse and thrust drop, but operability is preserved, in contrast to the thermocatalytic engine. According to the formula (A.A. Dorofeev. Fundamentals of the theory of thermal rocket engines (General theory of rocket engines) MSTU named after NE Bauman Moscow 1999):

$$W\max =\sqrt{\frac{2k}{k-\mathrm{one}}RT}[\mathrm{one}]$$

where Wmax is the gas flow rate through the Laval nozzle in vacuum at the optimal nozzle profile, k is the adiabatic index of water vapor, R is the gas constant of water vapor, T is the absolute temperature in the chamber. At a temperature of T = 273 K, Wmax reaches 1065 m / s. With a valve diameter of d = 10 mm and a maximum lift height x = 2.5 mm, the area of the cylindrical gap in the valve at its maximum lift will be:

f = xdπ = 7.85 × 10 ^-5 m ²

At a temperature of 273 K, the pressure of saturated water vapor is approximately Рнп = 600 Pa, while the gas density (if we consider the gas ideal) will be:

$$\rho g=\frac{Mr}{Vm}\times \frac{PnP}{R\mathrm{about}}$$

where Mr is the molar mass of water, Vm is the molar volume of gas at n.o., Po is the gas pressure at n.o. Thus, ρg = 4.82 * 10 ^-3 kg / m ³ . We assume that the hydraulic pressure loss on the valve is approximately equal to the pressure of saturated losses, then the mass flow through the valve will be:

$$Q=\mu \times f\times \rho g\times \sqrt{\frac{2\times RnP}{\rho g}}=1.133\times {10}^{-\mathrm{four}}\frac{\mathrm{to}g}{\mathrm{from}}$$

Then the engine thrust will be:

F = Q × Wmax = 120 mN,

which exceeds traction compared to the prototype. From the formula [1] it follows that the higher the temperature, the higher the flow rate and, as a consequence, the higher the impulse and thrust of the engine. Thus, in the presence of large available capacities, it becomes advisable to install the heating device directly in the chamber, in the area adjacent to the outlet of the tank, to increase the engine momentum.

Literature

1. Patent of the Russian Federation N 2374481, IPC F02K 99/00, 2008

2. Questions of electromechanics T.109. 2009 V.P. Khodnenko, A.V. Khromov (FSUE NPP VNIIEM) Corrective propulsion systems for a small spacecraft, p.30-31 (prototype).

3. A.A. Dorofeev. Fundamentals of the theory of thermal rocket engines (General theory of rocket engines) MSTU. N.E.Bauman Moscow 1999

Claims (2)

1. A liquid-gas jet engine containing a tank filled with a liquid working fluid, with an outlet in the lid, a chamber and a jet nozzle, characterized in that a control valve with an electromagnet and a spring is installed in it, installed in the chamber at the outlet of the tank after the separator phases of the working fluid, and water is used as the working fluid. 2. The liquid-gas jet engine according to claim 1, characterized in that the chamber is equipped with a device for heating the working fluid in the area adjacent to the outlet of the tank.

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