RU2498101C2 - Loaded case of solid propellant rocket engine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: loaded case of a solid propellant rocket engine comprises a charge released from the case bottom with a collar and a shield. The shield is arranged in the cavity between the case bottom and the collar and is fixed to the latter with an elastic ring, made in the form of two coupled circular shells along the large diameter. Shells of the elastic ring in the coupling zone are fixed to each other at the circular section via a circular gasket differing in colour from the shells.

EFFECT: invention makes it possible to provide for design mode of rocket engine operation at the initial section, to reduce swing in time of engine stabilisation and to increase reliability of its operation.

5 dwg

Description

The invention relates to the field of engineering, in particular to rocketry, and can be used in the design and development of curb cases of rocket engines of solid fuel (RDP).

Known are the designs of the equipped RPD case containing a charge unfastened from the bottom of the case by a cuff (see "Designs of solid propellant rocket engines", edited by Corresponding Member of the Russian Academy of Sciences, Doctor of Technical Sciences, Professor L.N. Lavrova. - M.: Mechanical Engineering, 1993. Fig.2.19 on p. 62).

As mining experience shows, such constructions are inherent in the possibility of particles and even pieces of fuel mass getting into the cavity between the cuff and the bottom of the body during filling of the body with solid fuel when it is equipped.

The presence of particles and pieces of fuel mass in the cavity between the cuff and the bottom is unacceptable, since their ignition when the engine starts leads to an unintended exit of the engine to the mode, reducing the efficiency of the RPM and, in some cases, can lead to destruction of the engine casing.

To prevent fuel mass from entering the cavity between the cuff and the bottom, the end part of the cuff can be fastened to the equipment before filling the casing, blocking the entrance to the specified cavity.

However, this is not possible in the recently found wide application of the design of the equipped case, having a charge with a partially burning end, the surface of which can be a significant part of the initial surface of the combustion of the charge, and the length of the forming cuff is significantly reduced.

This design of the equipped casing (see, for example, RU 2313685) is most effective for solid-state solid propellant solid propellant with small elongation with a charge having a blind channel.

In this design, it is practically impossible to completely exclude the possibility of particles of fuel mass entering the cavity between the cuff and the bottom of the casing during filling the casing with solid fuel when it is equipped without significant changes to the design.

Removing the fuel mass from the cavity between the cuff and the bottom of the housing is extremely difficult due to the small width of the gap with the large dimensions of the housing, and in some cases is not feasible.

Also known is the curb casing of a solid fuel rocket engine containing a charge unfastened by a cuff from the bottom of the casing and a screen located in the cavity between the bottom of the casing and the cuff and fastened to the last elastic ring made in the form of two annular shells conjugated over a larger diameter (see FR 2466627 A1, Fig.2-5), which is the closest analogue.

In this design, the entrance to the cavity between the cuff and the bottom of the body is blocked by an elastic ring, which eliminates the ingress of particles (pieces) of fuel mass into this cavity during the filling of the body with fuel when it is equipped, and thereby ensure the operability of the solid propellant rocket motor.

When the engine enters the mode, the elastic ring is destroyed under the influence of a pressure differential, ensuring the passage of the combustion products of solid fuel charge into the cavity between the cuff and the bottom of the housing, which is necessary from the condition of ensuring the strength of the charge.

However, in the known design, the destruction of the ring under the action of the combustion products when the solid propellant rocket enters the regime occurs randomly in unintended areas, since the shells of the elastic ring in the conjugation zone are individually sealed with their ends with the ends of the ring tissue reinforcement in which rigid tubes are fixed.

In the known construction it is impossible to program the process of destruction of the elastic ring, in particular, to ensure uniform destruction along the perimeter for the required time, the same for all manufactured engines, due to inevitable differences in the strength characteristics of the material of the shells of the elastic ring, in their thickness, etc.

The random destruction of the elastic ring leads to a non-uniform perimeter filling of the cavity between the cuff and the bottom of the body with solid fuel combustion products, the appearance of “pressure peaks” and, as a result, instability of the engine reaching the mode, while the time spread between the engines can be unacceptably large.

In addition, during the manufacturing process of the housing, it is practically impossible to determine the alleged fracture zones of the elastic ring.

At the same time, it is difficult to control the quality of bonding the shells before filling the housing with solid fuel, and the presence of areas of partial violation of the bonding of the shells is practically impossible to visually determine, which leads to an off-design process of fracture of the elastic ring, in particular, to variations in the time of its opening.

Thus, a significant drawback of the known technical solution is the instability of the output of the solid propellant rocket engine to the mode associated with the possibility of non-calculated destruction of the elastic ring, the opening of which ensures the passage of combustion products of solid fuel charge into the cavity between the cuff and the bottom of the housing.

The technical task of this invention is to increase the reliability of the equipped solid rocket motor with a stable output of solid propellant rocket motor to the mode.

The technical result is achieved by the fact that in the equipped casing of the rocket engine of solid fuel containing a charge, unfastened from the bottom of the cuff, and a screen located in the cavity between the bottom of the casing and the cuff and fastened to the last elastic ring, made in the form of two annular larger diameter the shells, the shells of the elastic ring in the mating zone are fastened together in an annular section through an annular gasket that differs in color from the shells.

The design of the elastic ring, the shells of which are fastened in the mating zone with each other on the annular section, allows the programmed process of opening the elastic ring under the influence of pressure drop when the engine enters the mode, while ensuring uniform opening of the elastic ring along its perimeter.

This embodiment of the elastic ring makes it possible to open it on the same surface with the gradual peeling of the shells from each other on the annular section of the bond, the same for all manufactured engines of width.

The presence of an annular gasket, which differs in color from the shells, allows you to visually control the width of the bonding section of the shells, to facilitate and simplify the process of detecting areas of partial adhesion failure, which allows them to be eliminated in a timely manner.

The set of essential features of the technical solution allows to ensure a stable output of the solid propellant rocket motor to the mode.

The essence of the proposed technical solution is illustrated by drawings.

Figure 1 shows a cross section of the curb body of the solid propellant solid propellant rocket in the area of the rear bottom: bottom 1 with TZP, channel charge of solid fuel 2, partially bonded to the body, armor cuff 3, screen 4.

Figure 2 shows the area of the elastic ring 5, fastening the armor cuff 3 with the screen 4.

The elastic ring 5 consists of two annular shells 6, 7 conjugated over a larger diameter, which are fastened together along the inner surface in an annular section of width l.

The shell 6 is bonded to a smaller diameter with a screen 4.

The shell 7 is bonded to a smaller diameter with an armor cuff 3.

Figure 3 shows the fastening of the shells 6, 7 through the annular gasket 8.

Figure 4, 5 shows the elastic ring 5 at the beginning of the operation of the solid propellant rocket motor.

In the process of filling the casing with solid fuel when it is equipped, the presence of a preformed elastic ring 5 in the casing 5 (Figs. 1, 2) allows you to block the entrance to the cavity between the cuff 3 and the bottom 1 of the casing and thereby prevent particles (pieces) of fuel mass from falling into this cavity .

At the same time, the screen 4, which is fastened in small diameter with equipment, allows you to create a vacuum in the cavity between the cuff 3 and the bottom 1 through the filters installed in it (not shown in Fig.) Before filling the body with fuel mass.

After filling the case with solid fuel, the quality control of gluing the shells 6 and 7 is carried out on the width l of the bonding section, since gluing during routine maintenance related to the manufacture of the charge may be partially violated.

The presence of the gasket 8, which differs in color from the shells 6 and 7, can significantly simplify the quality control of gluing in a section of width l and refinement in case of partial breaking of gluing before filling the body with solid fuel.

The need for refinement of the body will be indicated by the appearance of a colored area in the area of fastening of the shells 6, 7 of the elastic ring 5 against the background of their surfaces.

At the beginning of the operation of the solid propellant solid propellant rocket igniter and the surface of the open end of the charge create a pressure drop on the elastic ring 5, resulting in a process of gradual peeling of the shells 6, 7 from each other (figure 4).

After complete peeling, the elastic ring 5 opens into two parts (Fig. 5) and the solid fuel combustion products fill the cavity between the cuff 3 and the bottom 1.

The fastening of the shells 6, 7 on the annular section of the same width l for all engines ensures the break of the elastic ring 5 at the same time and at the same pressure drop, which is necessary to ensure the stability of the output of the engine to the regime and to reduce the variation in operating time between manufactured engines.

The proposed technical solution allows to provide a design mode of operation of the solid propellant rocket motor in the initial section, to reduce the spread in the time the engine reaches the mode and increase its reliability.

Claims (1)

An equipped casing of a solid fuel rocket engine containing a charge, unfastened by a cuff from the bottom of the casing, and a screen located in the cavity between the bottom of the casing and the cuff and fastened to the last elastic ring made in the form of two annular shells conjugated with a larger diameter, characterized in that the shell elastic rings in the mating zone are fastened together in an annular section through an annular gasket that differs in color from the shells.

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