RU2561820C2 - Staroverv's-8 rocket engine (versions) - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: nozzle-free rocket engine comprises the grain of solid rocket propellant with one or several lengthwise channels filled with propellant of high combustion rate than that of the main propellant. Grain outer surface is reinforced with pipe of melting or combustible material, or reinforced with high-modulus fibres. Note here that said fibres are directed across the grain axis, or across and along, or in solid spiral in different directions.

EFFECT: higher engine efficiency, higher strength of the grain.

5 cl, 1 dwg

Description

The invention relates to non-nozzle end-face rocket engines and is suitable for all types of rockets - from small-caliber uncontrolled to strategic and space rockets. This engine is especially suitable for missiles with high final speed.

Known non-exhaust engines with channel and end combustion, but they have a low specific impulse, since it is impossible to ensure the effective expansion of the resulting gases. Known for my "Open Frame Engine" pat. No. 2398125, in which to obtain the desired sufficiently high linear burning speed of the fuel, the checker has longitudinal holes along the entire length, filled with a mixture based on black powder or otherwise. To increase the strength of the checker, it has longitudinal reinforcement with high modulus fibers.

However, the same technical solutions can ensure that the nozzle surface in the form of an expanding cone is provided at the back of the checkers, which ensures the expansion of the gases formed with an efficiency equal to that of the present jet nozzle.

OPTION 1. So, this engine contains a block of solid rocket fuel, having one or more longitudinal channels for the entire length of the block, filled (filled) with faster burning fuel than the main fuel (hereinafter “leader fuel”, and the channel with it is “ leader charge ”).

So faster burning fuel can be a mixture based on black powder. Moreover, to change the burning rate of this mixture, it may partially contain ammonium nitrate (anhydrous) instead of potassium nitrate (for example, 50: 50%). Or it may contain finely dispersed low-explosive explosives (for example, trinitro-m-xylene). To reduce the burning rate, the mixture may contain ballast combustible or non-combustible substances, for example hexamethylenetetramine.

The main fuel is required to be of sufficient strength. The main fuel can be existing solid fuels, for example ammonium perchlorate or ammonium dinitramide in polymerized methacrylic acid ester (in plexiglass, radiation polymerization), in polyurethane, in synthetic resins, etc.

At the same time, in the process of burning checkers, the point of combustion front of the quick-burning mixture will be ahead of the process of burning the main fuel, and will be, as it were, the top of the cone facing back the bell. That is, if the said channel is one, then an expanding jet nozzle is formed, consisting of checker material, that is, from fuel (hereinafter “nozzle”). See attached sketch.

True, this engine needs an accurate selection of the burning rate of the fuel, or rather, two fuels. If in a conventional solid-fuel engine, knowing the burning speed of some fuel at a given pressure, we select the desired nozzle diameter, then in this engine we must do the opposite - knowing the nozzle cut-off diameter, CHOOSE THE BURNING SPEED of the main fuel and leader fuel, and, with a different pressure. But what is the gain - there is no housing or nozzle, no step-up is necessary!

To verify the operability and efficiency of such an engine, we compare it with a conventional solid-propellant rocket engine (RDTT) with the same specific heat of fuel, with the same nozzle exit area and the same nozzle exit pressure. Suppose, in a solid propellant rocket engine, the mass of fuel “M” burns per second. We select the burning rate of the main fuel and the leader fuel of this engine so that the taper of the combustion front is 10-15 degrees to the side (approximately as in a real jet nozzle), and so that “M” of fuel burns per second on the resulting conical surface. That is, fuel consumption is the same. The specific heat of the fuel and the pressure at the nozzle exit are also the same, therefore, the temperature of the gases will be the same. If the gas flow through the nozzle exit and the gas parameters are the same, then the gas flow rate is the same. That is, the operation of this engine is completely identical to the operation of a conventional solid propellant rocket motor.

So that the edges of such a nozzle do not break off from the pressure drop inside and out (although this difference in the nozzle exit is small or even absent if the pressure at the exit is chosen equal to atmospheric), the outer surface of the checker can be reinforced with high-modulus fibers. The fiber module must be larger than the fuel material module, so that they perceive the tensile load. But, unlike the prototype, the fibers should be oriented mainly transverse to the axis of the checker. Or both transversely and longitudinally. Or in a volumetric spiral in different directions.

So that the fibers do not dangle behind the nozzle as the checkers burn, they must be either fusible (synthetic high-strength high-modulus fibers such as 3ylon, Dainima Spectra, Vectran, low-melting grades of fiberglass), or combustible (the same synthetic fibers, carbon fiber, combustible metals, for example, from aluminum-magnesium alloy).

Or, as a reinforcement, the checker can be enclosed in a thin-walled tube of these materials.

If there are several channels, then they should be located fairly evenly over its cross section, for example, in a honeycomb order, in squares, or better, in circles. At the same time, not one, but several expanding nozzles located in the same plane are formed in the back of the checker, that is, the back end of the checker will have a multicone shape. The same shape of the butt should be and initially - when igniting the checkers. At the same time, the time spent by the burning fuel components in the reaction zone will be reduced, however, as the experience of rocket modeling shows, this is not significant - even micromodels of rockets the size of a half fly well.

This shape allows you to better use the checker to the very end, when the combustion cone becomes a truncated cone when approaching the front end of the checker. And the efficiency of a multicone nozzle is the same as that of a single cone.

Due to some manufacturing inaccuracy or combustion unevenness, the nozzle of such an engine may become somewhat skewed during the combustion process, therefore, for unguided missiles with such an engine, rotation stabilization is especially relevant. This is especially true also because it is difficult to install rear aerodynamic stabilizers on a rocket with such an engine - there is nothing to fix them with.

However, they can be mounted on a sliding clip. In this case, the clip can shift forward as the checkers burn themselves, due to the presence of an expanding conical section at the back - this section will be part of the said expanding nozzle and will create thrust directed forward, similar to my invention “Self-feeding open-frame engine” pat. 2431052. Or, the clip can be moved forward by means of a thread connected to a forced drive, for example, a turbine in a gas stream or in an air stream (similar to my aforementioned invention, Pat. No. 2398125).

It is especially advisable to use such light and cheap engines in multiple launch rocket systems that are forcibly stabilized by rotation (for example, Grad).

But such an engine can also be used in a guided missile, in which flight stabilization is carried out by its control system, for example, in air-to-air, ground-to-air, air-to-ground missiles, in medium-range missiles, in universal missiles similar to the Standard-3M missile. True, a stable flight of such a rocket without rotation and without stabilizers is possible when using only one aerodynamic scheme - “Weathervane duck” in my stalemate. No. 2410286. Or with the use of gas-dynamic control. Self-stabilization will be carried out due to the fact that the fuel, as a rule, is lighter than the payload (if it is well arranged), and therefore the center of gravity will be in front of the aerodynamic focus.

OPTION 2. To start the rotation, the reactive force of the piece itself can be used. To do this, the checker should have several channels (at least 2, optimally 6 or more), and along the entire length or in the back of the checker, the channels on the periphery (that is, everywhere except on the longitudinal axis) are spiral or inclined to one side. Spiral channels are more efficient, but inclined - straight, and therefore easier to manufacture. It is difficult to make inclined or spiral channels along the entire length of the checker; therefore, it is sufficient to obtain the desired rotation speed if such channels are only at the back of the checker. This rear part can be manufactured separately and glued to the main checker in compliance with the coincidence of the channels.

Such channels form several jet nozzles inclined towards the longitudinal axis of the checker (they must be molded on the checker initially), which will twist it when the rocket starts.

It should be noted a feature of the manufacturing technology of such an engine: the channels can be drilled or cast, and then filled with a quick-burning mixture. But another option is also possible - sections with a quick-burning mixture are made in advance in the form of wicks (for example, nitrated cotton twine, then impregnated with the composition of black powder). These wicks are stretched between the front and rear ends (grease their casting molds with a release agent), the ends are placed in a pipe, for example, from a zylon, and a pyrotechnic mixture of solid fuel in the form of epoxy, polyester, or other resin is added in a vertical position with the addition of perchlorate. If Plexiglass will be used, then its thermal polymerization is impossible, it is necessary to apply radiation polymerization.

The attached sketch shows this engine in option 1 with one channel.

The engine consists of solid rocket checkers 1 in the form of a cylinder. On the axis of the checkers there is a channel 2 with a powder mixture. Outside, the checker has a reinforcing layer in the form of a thin-walled zylon winding 3 with epoxy resin. Behind there is a conical recess 4, forming an expanding jet nozzle.

To spin the rocket in flight, the checker can have inclined stabilizers mounted separately or on a common clip (for simultaneous separation), which separates after burning the end of the checker.

The engine works like this: the fuel in channel 2 burns faster. And therefore, the combustion front of the main fuel is formed in the form of a cone, from which the gases formed flow at a supersonic speed. Traction is created.

It should be noted another positive quality of such an engine - a rocket does not need a multi-stage design to achieve high final speeds. A two- or more-stage design is used only in order to dump tanks, housing, liquid engine, nozzle (in a frameless engine) that become too heavy (in relative terms). But in this engine there is none of this. Even if we conditionally consider the winding of the checker in one or two layers as high-modulus fibers with the body, this “body” weighs only 0.1-1% of the mass of the engine and is shortened as the engine runs. That is, the achievement of any real speeds (for example, 14.1 km / s) is possible in one step. True, in this case, at the end of acceleration, a large overload will act on the payload. And, if the payload does not withstand this, then this can be avoided by applying again a multi-stage design in which the second stage checker will have a smaller diameter and less traction. But at the same time, the disadvantages of the usual multi-stage design do not appear - there are no tanks, bodies, nozzles. Or you can use a cone motor.

Claims (5)

1. The engine is a nozzle-free rocket containing a solid rocket rocket that has one or more longitudinal channels along the entire length of the block, filled (filled) with faster burning fuel than the main fuel, and characterized in that the outer surface of the block is reinforced with high modulus fibers, moreover, the fibers are oriented transversely to the axis of the checker, either transversely and longitudinally, or along a volumetric spiral in different directions, or the outer surface of the checker is hardened by a pipe of melting or combustible material la 2. The engine under item 1, characterized in that the more quickly burning fuel is a mixture based on black powder. 3. The engine according to claim 2, characterized in that for changing the burning rate of this mixture it partially contains ammonium nitrate instead of potassium nitrate, or contains fine explosives of low-explosive action, for example, trinitro-m-xylene, or contains ballast combustible or non-combustible substances for example hexamethylenetetramine. 4. The engine according to claim 1, characterized in that it has a sliding clip with stabilizers, and in the rear of the clip there is an expanding conical section. 5. The engine according to claim 1, characterized in that the cage is shifted forward by means of a thread connected to a forced drive, for example, with a turbine in a gas stream or in an air stream.

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