RU2313685C1 - Solid-propellant rocket engine - Google Patents

Abstract

FIELD: rocketry.

SUBSTANCE: invention can be used in designing solid-propellant rocket engines with high propellant loading ratio, particularly, with blind channel. Proposed solid-propellant rocket engine has charge with central channel connected with body and burning end face, nozzle assembly and igniter. The latter is arranged in zone of mating of burning end face and channel of charge. Ignition consists of housing in form of tubular ring with perforation filled up with pyrotechnical compound. Perforation is made in form of holes arranged over circumference with axis common with axis of engine and pointed inside charge channel, and holes pointed to zone of mating of burning end face and change channel.

EFFECT: improved energy producing characteristics and provision of quick and stable coming to conditions with high propellant loading ratio owing to simultaneous ignition of charge over entire burning surface.

3 cl, 5 dwg

Description

The invention relates to rocket technology and can be used to create solid propellant rocket engines (solid propellant rocket engines), in particular, having a large volumetric filling factor, in particular with a blind channel.

Known constructions of solid propellant solid propellant rocket engines containing a charge with a blind channel or a charge with a narrow through channel and fully or partially detached burning ends. These solid propellant motors are characterized by the fact that a significant part of the initial surface of the combustion of the charge (> 50%) is made up of the ends, which at the initial moment of the engine’s operation are pressed against the heat-shielding coating of the solid propellant motor or have a slight gap with it. Because of this, when using ignitors of a traditional design, these engines have a very long and time-unstable exit to the regime (ignition of the charge and a set of working pressure in the chamber), which entails significant loss of energy characteristics (ballistic efficiency) of the engine and the need for increased control efforts at the initial stage of work (which is characterized by a maximum level of disturbing influences), which leads to an increase in the passive mass of the engine and, again, to a decrease ballistic efficiency.

Known solid propellant solid propellant rocket engine containing a housing with a central recessed nozzle, a charge with a central channel, an igniter installed on the recessed part of the nozzle, consisting of a housing filled with a pyro-composition in the form of a tubular ring with perforations in the form of holes located around the circumference and directed inward (along the wall) of the charge channel (V.V. Kalinin et al. "Non-stationary processes and methods for designing solid propellant assemblies", M., Mechanical Engineering, 1986, p. 17, 18, Fig. 1.7). If the main part of the initial surface of the combustion of the charge is created by burning ends (charges with a small diameter or a small elongation of the channel), then the engine will have the above-mentioned disadvantages: a prolonged, unstable exit to the regime with a corresponding decrease in ballistic efficiency and an increase in passive mass.

The technical task of the present invention is to improve the energy characteristics of the engine by providing faster and more stable ignition of the charge over the entire combustion surface.

The technical result is achieved by the fact that in the known solid propellant rocket engine containing a housing with a central recessed nozzle, a charge with a central channel mounted on the recessed part of the nozzle is an igniter consisting of a housing filled with a pyro-composition in the form of a tubular ring with perforations in the form of holes located around the circumference and directed inward (along the wall) of the charge channel, in the igniter, perforation is additionally performed in the form of holes directed to the interface between the burning end and the charge channel.

In addition, the holes forming the perforation can be located along the perimeter of the igniter in groups between which there is no perforation, and the igniter body can be made in the form of one or more parts of a tubular ring, between the ends of which there are gaps.

Figure 1 shows a solid fuel rocket engine made in accordance with the present invention.

Figure 2 is a partial view of I in figure 1 (enlarged).

Figure 3 - the movement of gas flows in the gap along the end of the charge.

Figure 4 - the movement of gas flows in the gap with the location of the holes on the igniter in groups.

Figure 5 - the movement of gas flows in the gap when performing an igniter of several parts.

Figure 1 shows the solid propellant rocket engine consisting of a housing 1, a central nozzle 2, a solid fuel charge 3 with a blind channel 4 and a detached, partially armored burning end 5. In the vicinity of the interface zone 7 of the channel wall and the burning end of the charge, an igniter 6 is located.

Igniter 6 consists of a housing 8 (FIG. 2), which is a tubular ring (annular tube) and equipped with a pyro-compound 9. Perforation in the form of two groups of holes arranged in circles is made on the igniter body. The holes of the first group 10 are directed inside the charge channel along its wall, and the holes of the other group 11 are directed into the interface zone 7 of the channel wall and the burning end face 5 of the solid fuel charge.

When the igniter is activated, the flow of hot gases from the holes of the first group sets fire to the surface of the charge channel. Since on all charges in the interface between the channel wall and the end of the charge, a conical chamfer is made for gas to enter the stagnant region, when gases flow out of the holes of the second group, an increased pressure region is created in this zone due to braking and reversal of the gas flow. There is a so-called "proppant" effect, as a result of which a gap is formed (increases) between the end of the charge and the thermal current transformer 12 of the engine casing. The flow of hot gases from the holes of the second group, injected into this gap, leads to its even greater increase and ignites the end face of the TT charge. The creation of pressure in the cavity of the charge channel during its ignition also contributes to an increase in the gap between the end of the charge and the thermal current transformer of the housing and improves the conditions of ignition of the charge over the entire surface.

Thus, almost simultaneous ignition of the charge is ensured over the entire burning surface, which can significantly reduce the time to exit to the mode and increase the energy characteristics of the engine.

However, with an increase in the radial length (length along the generatrix) of the burning end of the charge, it may turn out that the proposed design will not be sufficiently effective. The fact is that when gases are injected into the gap along the end of the charge along the entire perimeter, due to the deceleration of the gas flow, a stagnant zone is formed at the top of this gap, into which practically no hot gas comes from the igniter and there is no heat influx to the surface of the charge. This zone can block part of the burning end of the charge, which worsens the ignition conditions. Schematically, the movement of gas flows 13 is shown in FIG. 3, which also shows the boundary of the stagnant zone 14 and the tip of the armor cuff 15.

To overcome this, it is necessary to organize the so-called "flow" system of washing the end of the charge with hot gases from the igniter.

This is achieved in two ways.

The first method is to blow hot gas into the gap between the end face of the charge and the charge protection plate of the housing on the entire perimeter, and in separate sections, for which the holes of the perforation of the igniter body, designed to blow gas into the gap, should not be placed uniformly around the perimeter, but in separate sections, between which the perforation is not to be done, as shown in figure 4, where 16 are parts of the igniter body, free from perforation.

The second way of organizing a "flowing" flushing of the end of the charge is to divide the igniter body along the perimeter into several parts, between which there will be free space for gas to pass from the gap between the end of the charge and the charge transformer, as shown in Fig. 5, where 17 are parts of the ignitor body .

The igniter body may also be made not of several parts of the tubular ring, but of one of its parts - the so-called "broken ring" - between the ends of which there will be free space for the passage of gases.

Figures 4 and 5 also show a pattern of washing the end of the charge with gas flows 13, from which it can be seen that due to the displacement of the cooled stagnant gases, the stagnant zone in the gap between the end of the charge and the TZP is practically absent.

Thus, the present invention allows for a quick and stable exit to the solid propellant rocket motor mode having a high volumetric filling factor when it is started, and thereby improve its energy characteristics.

Claims (3)

1. A solid propellant rocket engine (RDTT) comprising a charge bonded to the body with a central channel and a detonated burning end face, a nozzle block located in the interface between the burning end face and the charge channel, an ignitor consisting of a housing filled with a pyrostructure in the form of a tubular ring with perforation made of holes located on a circle having a common axis with the axis of the engine, and directed into the charge channel, characterized in that the perforator in the form of holes is additionally made in the igniter body, directed into the interface between the burning end and the charge channel. 2. The engine according to claim 1, characterized in that the holes forming the perforation are located along the perimeter of the igniter in groups between which there is no perforation. 3. The engine according to claim 1, characterized in that the igniter body is made in the form of one or more parts of a tubular ring, between the ends of which there are gaps.

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