RU2570911C2 - Staroverv's rocket engine-2 (versions) - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: claimed rocket engine comprises the combustion chamber whereto fed is the mix of borane and ammonia, or the solution or borane solution in the liquid ammonia. The components are fed at the following ratio: diborane - 44.8±10 wt %, ammonia - 55.2±10 wt %. Additionally, 0.0001-1 wt % of the bulk of reacting substances of fine coal, and/or soot, and/or graphite, and/of methane are fed into said combustion chamber. In compliance with the second version, the rocket engine comprises the combustion chamber or the body with nozzle running on liquid or solid propellant. Besides, the exhaust gas of the engine running on diborane, or tetraborane and ammonia are fed additionally to the combustion chamber or to the body.

EFFECT: higher specific thrust pulse.

4 cl

Description

The invention relates to rocket engines of liquid and solid fuels.

Rocket engines are known, see, for example, my “Self-feeding Open Frame Engine”, US Pat. No. 2431052. All existing chemical rocket engines use the principle of high-temperature heating of gas or a gas-dust working fluid (dust is solid fractions of decomposed solid rocket fuel). This is done in order to increase the flow rate of the working fluid from the jet nozzle. This speed is determined, firstly, by the speed of sound in the gas and, secondly, by the degree of expansion of the gas in the expanding supersonic jet nozzle, and reaches 4000 m / s in the best engines. Moreover, engine parts operate in very intense thermal conditions, even taking into account their cooling.

Meanwhile, the speed of sound in hydrogen even at normal temperature and pressure of 1330 m / s. And if you also slightly increase the temperature of hydrogen, then the speed of sound in it and the speed of its outflow from the nozzle will increase sharply. For example, hydrogen with a temperature of only 650 degrees C (this is below its ignition temperature) will have a sound speed of 2360 m / s, and will be able to accelerate itself in the jet nozzle and disperse dust particles to a speed of about 4300 m / s. That is, a “cold rocket engine” is obtained in which, due to adiabatic expansion, the gas at the outlet of the jet nozzle can have approximately the ambient temperature. This is the basis of the idea of this invention. The purpose of the invention is to increase the speed of a jet stream and the specific impulse of a rocket engine. And also, in some cases, a decrease in unmasking infrared radiation.

OPTION 1. This engine contains a combustion chamber (we will call it that, although there is no “combustion” process in it), into which a mixture of borane and ammonia, or a solution or emulsion of borane in liquid ammonia, is supplied under pressure.

When the reaction is initiated by a heat source, the exothermic decomposition of diborane (up to 300 degrees C) occurs first with the release of heat 38.5 kJ / mol, after which the released boron interacts with two ammonia molecules. Example 1

B2N6 + 2NH3 = 2BN + 6H2 + 451 kJ / mol

That is, the specific heat release is 7.27 kJ / g, which is approximately like most solid rocket fuels. Approximate calculations show that the reaction temperature will be at a constant pressure of 1800 degrees C. The speed of sound in such hydrogen will be 3510 m / s, and the speed of the reactive dust-gas jet will be about 6300 m / s. However, the too small amount of hydrogen released raises doubts as to whether it can accelerate the entire initial mass to such a speed. The verification calculation (excluding component heating) according to the law of energy conservation showed that the maximum speed even at 100% efficiency It will be 3810 m / s. Really - even less.

But since the efficiency 100% does not happen, then an unexpected conclusion follows from what has been said - this engine does not need an expanding supersonic nozzle. Tapering enough. Preferably, with a small cylindrical part at the outlet, in order to better disperse the dust particles. The absence of a nozzle confuser will significantly reduce the weight of the engine and sharply reduce its dimensions.

The relatively low operating temperature will significantly facilitate and simplify the design of the engine. For example, a tungsten engine can operate without cooling, and a titanium engine must have cooling, but will be much lighter than a tungsten engine.

Since boron reacts with ammonia and nitrogen resulting from its thermal decomposition above 1200 degrees, the whole reaction proceeds in an avalanche-like manner, that is, independently.

The formation of boron nitride is more intense in the presence of a reducing agent. Such may be hydrogen evolved. To increase the reaction rate, the presence of finely divided coal, soot, graphite, or a small amount of methane (0.0001-1% by weight of the reacting substances), or a mixture thereof, is desirable. Methane at a temperature above 1100 degrees C exothermically (with a specific heat of 4.68 kJ / g) decomposes with the release of two molecules of hydrogen and carbon in the form of soot, which will be a catalyst for the formation of boron nitride.

As can be seen from the reaction, the stoichiometric ratio of diborane and ammonia should be 27.67: 34.06 and 12.1 g / m of hydrogen will be released. In reality, up to 10% deviations in one direction or another are possible due to the difference in reaction rates. That is, the stoichiometric ratio in percent is 44.8: 55.2, and 19.6% of hydrogen will be released in relation to the initial mass.

For such an engine to start, it needs an initial heat source. It can be a burner or a pyrotechnic checker mounted on the launcher, which is directed inside the combustion chamber. For some time, it warms up the chamber, and then, after supplying the fuel components (we will call it that, although it does not “burn”), it initiates the beginning of their reaction.

A more interesting option is that a checker of quick-burning solid rocket fuel is installed in the combustion chamber itself - in the center and / or on its walls. Such a checker, with the correct calculation of its power, immediately begins to move the rocket, warms up the combustion chamber and at the end of the work (about 25-10% of the power) initiates the reaction of fuel reagents. It is possible to smoothly replace the performance of the checkers by smoothly supplying fuel to the combustion chamber. The working time of such a checker is small - seconds or even fractions of a second. Since it is desirable to warm the walls of the combustion chamber, then if there are two checkers in the center and along the edges of the combustion chamber, the central checker should work a little longer to warm up the walls that open after the side checker is completely burned out.

OPTION 2. To increase the specific heat, the engine can be combined with a classic rocket engine, liquid or solid fuel. That is, such an engine contains a combustion chamber or a housing with a nozzle, runs on liquid or solid rocket fuel, and is characterized in that the exhaust chamber of an engine operating on diborane or tetraborane and ammonia is additionally fed into the combustion chamber or into the housing of a solid propellant rocket engine.

As a result of burning conventional (redox) rocket fuel and the operation of a hydrogen engine, a gas-dust mixture is obtained in which the speed of sound will be lower than hydrogen, but higher than in conventional rocket gases. The total impulse of such an engine can turn out to be higher than a purely hydrogen engine, and higher than a redox engine (a series of experiments is required). But, even if the pulse turns out to be approximately the same, such an engine continues to retain the advantage of a low process temperature, that is, it will have reduced infrared visibility and low thermal tension of the engine structure, i.e. its low weight and lack of cooling.

Example 2. In a classic liquid rocket engine (for example, oxygen-kerosene), the engine exhaust is additionally supplied according to option 1, in an amount of 1: 1. The engine runs as usual.

Claims (4)

1. A rocket engine containing a combustion chamber into which a mixture of borane and ammonia or a solution or emulsion of borane in liquid ammonia is fed under pressure, characterized in that the components are supplied in the following ratio: diborane - 44.8 + -10%, ammonia - 55 , 2 + -10%, moreover, 0.0001-1% of the mass of reacting substances of finely dispersed coal and / or soot, and / or graphite, and / or methane is supplied to the combustion chamber. 2. The engine according to claim 1, characterized in that a burner or pyrotechnic checker mounted on the launcher is directed into the combustion chamber. 3. The engine according to claim 1, characterized in that in the center and / or along the edges of the combustion chamber a checker of solid rocket fuel is installed. 4. A rocket engine containing a combustion chamber or a housing with a nozzle operating on liquid or solid rocket fuel, characterized in that the exhaust chamber of an engine operating on diborane or tetraborane and ammonia is additionally fed into the combustion chamber or into the housing of a solid propellant rocket engine.