RU2425246C1 - Combined charge of solid propellant rocket engine with flame arresting effect of effluent jet of combustion products (versions) - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: combined charge of solid propellant rocket engine with flame arresting effect of effluent jet of combustion products includes solid-propellant grain and grain of flame arresting compound, which is installed near one of edges of solid-propellant grain. As per the other version, charge of solid propellant rocket engine is made in the form of multi-grain charge including several grains of flame arresting compound, which are equally located along the perimetre. In each of the versions the fire arch of grain of flame arresting compound and its weight are made considering the ratios determined by this invention.

EFFECT: invention allows improving reliability and safety of solid propellant rocket engine.

6 cl, 2 dwg

Description

The invention relates to the field of rocket technology, and in particular to the field of developing a design of a charge of solid rocket fuel (TRT), including an additional checker (checkers) of flame-retardant composition (ASG), which ensures the safety of the use of charge in rocket engines of solid fuel (solid propellant rocket engine) during combat use - operation.

It is known that in the combustion products (PS) of the TRT flowing out of the solid propellant nozzle contain incomplete combustion products (Н ₂ and СО), which are oxidized upon interaction with atmospheric oxygen, which leads to the combustion of the PS stream in the atmosphere with the formation of a high-temperature plume and an abrupt increase in the temperature of the gases flowing through the nozzle of the solid propellant from 800-1000 K to 2000 K and more (the so-called phenomenon of the "secondary torch"). When launching aircraft rockets equipped with solid propellant rocket engines from under the fuselage of carrier aircraft, the presence of a “secondary torch” can lead to loss of gas-dynamic stability of aircraft engines (AD) due to suction of the torch into the diffuser of the carrier aircraft’s AD, namely to their surge (stalling) ) When using solid propellant rocket engines as brake engines of landing platforms with military equipment from transport aircraft, this equipment can be damaged due to the direct impact of the “secondary torch”, as well as fires at the landing site.

To eliminate the phenomenon of the “secondary torch”, additional checkers made of PGS (US Pat. No. 3,166,696-prototype) are used in the TPT charge, the formulation of which contains ≈40-70% potassium salts (potassium sulfate, potassium perchlorate).

The disadvantage of the prototype is reduced efficiency (the ratio of the combustion rates of TPT and ASG is not optimized, as well as the ratio of the second weighted expenses of TRT and ASG, and the ASG formulation itself has a reduced concentration of potassium-containing compounds). This does not allow to realize the highly efficient design of solid propellant rocket engines for aircraft missiles and brake engines of landing platforms.

An object of the invention is to develop the design of the combined charge of the TRT, providing a stable flame-retardant effect of the expiring stream of combustion products.

The technical result of the invention is to perform a combined charge for a rocket engine of solid fuel with a flame-retardant effect of an expiring jet of combustion products, made in the form of a solid rocket fuel checkers and checkers of flame-retardant composition. In this case, the checker made of ASG is installed at one of the ends of the TRT checker. The burning arch of checkers from ASG is carried out taking into account the conditions:

e _ASG · U _TRT = e _TRT · U _ASG

where e _ASG is the burning arch of checkers from a flame-retardant composition;

e _TPT - burning arch of solid rocket fuel drafts;

U _TPT - burning rate of solid rocket fuel checkers;

U _ASG - burning rate checkers flame retardant composition;

and the mass of the ASG checkers (m _ASG ) is made taking into account the ratio:

(0.05) m _TRT <m _ASG <(0.10) m _TRT ,

where m _TPT is the mass of TPT pieces.

The technical result of the invention also consists in performing a combined charge for a solid propellant rocket engine with a flame-extinguishing effect of an expiring jet in the form of a multi-cup charge from TRT and several checkers made of ASG and uniformly installed around the perimeter of the multi-cup charge TRT.

In this case, the burning set of ASG checkers (yet) is made subject to the conditions:

e _ASG · U _TRT = e _TRT · U _ASG ,

where e _ASG is the burning arch of ASG checkers;

e _TPT - burning arch of checkers TRT;

U _TPT - combustion rate TRT;

U _ASG - burning rate of ASG;

and the mass of ASG checkers (m _ASG ) is made taking into account the conditions:

(0.05) m _TRT <m _ASG <(0.10) m _TRT

where m _TPT is the mass of TPT pieces.

The technical result of the invention also lies in the implementation of the formulation of ASG for the above options for charges in the following ratio of components (wt.%):

Potassium Chloride - 46.0-48.0

Potassium sulfate - 35.0-37.0

Polyvinyl butyral - 7.0-9.0

Dibutyl phthalate - 3.0-4.0

Oleic acid - 1.0-2.0

Epoxy resin -1.5-2.5

Paraffin-0.5-1.5

Graphite - 0.3-0.7

Polyethylene polyamine - 0.3-0.7.

The solid rocket checker in the above charge variants is made of ballistic solid rocket fuel or mixed solid rocket fuel.

The essence of the invention lies in the efficiency of the implementation of the flame retardation of the combustion products of the TRT behind the nozzle of the taxiway, both due to the formulation of the flame retardant composition (ASG) and the charge structure as a whole. The presence in the flame-retardant composition of the thermal decomposition products of potassium perchloride and sulfate, which are realized in the flowing stream of PS, including in the form of potassium ions (K ⁺ ) and chlorine ions (Cl ^- ), which have an inhibitory effect [see Semenov N.N. "On some problems of chemical kinetics and reactivity." M .: Publishing House of the Academy of Sciences of the USSR, 1958], it is possible to efficiently bind free radicals in the combustion products of TPT and thereby eliminate the burning out of products of incomplete oxidation with a subsequent increase in the temperature of the outflowing jet. Compliance ratio:

(0.05) m _TPT <m _ASG <(0.10) m _TPT promotes effective flame retardation:

- when m _ASG / m _TRT <0.05, a satisfactory quenching of the flame stream is not achieved,

- at m _ASG / m _TRT > 0.10, the characteristics of the solid propellant rocket motor (traction impulse) are significantly deteriorated. Within m _ASG / m _TRT = 0.05 ... 0.10 - stable flame extinguishing of the PS jet is ensured with an acceptable level of ballistic characteristics of solid propellant rocket engines.

The placement of ASG checkers uniformly along the periphery (perimeter) of the multi-plate charge helps to increase the efficiency of the flame extinguishing process with a minimum number of ASG checkers.

Compliance with the ratio e _ASG · U _TRT = e _TRT · U _ASG allows you to provide the effect of flame suppression during the whole time of operation of the solid propellant rocket motor.

At the same time, up to 80 ... 85% of potassium-containing salts are introduced into the PGS formulation, and the homogeneity, homogeneity, and rheological characteristics of the flame-retardant composition are ensured by the introduction of polyvinyl butyral, dibutyl phthalate (DBP) and oleic acid in the specified proportions.

The solidity and strength of the ASG checkers also contributes to the introduction of epoxy resin and polyethylene polyamine into the ASG formulation, and the introduction of paraffin, as well as graphite, which simultaneously regulates the ASG burning rate, contributes to satisfactory rheological characteristics when pressing the ASG checkers.

The introduction of an increase in the amount of potassium-containing substances in the ASG formulation compared to the prototype makes it possible to substantially reduce the amount of energetically inert materials in the combined charge as a whole (i.e., the actual mass of the ASG charge) and, thereby, increase the energy characteristics of the combined charge as a whole.

The use of ASG recipes according to this application allows you to implement an effective design of the combined charge of TRT to aircraft missiles and brake solid propellant rocket landing platforms, namely in the form of:

1. A multi-cup charge of TRT, equipped with checkers made of ASG (Fig 1) and evenly installed around the perimeter of the charge.

2. Monoblock charge from TRT, equipped with a checker from ASG (Figure 2).

Graphic materials

Figure 1 - combined mnogoshechnaya charge of checkers TRT and ASG;

Figure 2 - combined charge with a checker-candy bar TRT and a checker ASG, where

1 - checker TRT;

2 - checker from ASG.

An example of practical implementation. Patented charge design is implemented as:

Example I

Multi-shell charge to the brake solid propellant rocket landing platform (Figure 1)

1.1. The geometric dimensions of the checkers TRT:

outer diameter - 28.0 mm

channel diameter - 8 mm

length - 320.0 mm

quantity - 34 pcs.

weight - 10.1 kg

1.2. The geometric dimensions of the ASG checkers (the recipe is in accordance with the patented technical solution):

outer diameter - 28.0 mm

channel diameter - 5.0 mm

length - 320.0 mm

quantity - 3 pcs.

weight - 1.0 kg

Example II

Monoblock charge for an aircraft missile in the form of checkers from TRT and checkers from ASG (Figure 2).

2.1. The geometric dimensions of the TRT checkers:

outer diameter - 76.0 mm

inner channel - shaped, star-shaped

length - 750.0 mm

weight - 3 kg

2.2 The geometric dimensions of the checkers ASG (recipe - in accordance with patented technical solution):

outer diameter - 70.0 mm

channel diameter - 40.0 mm

length - 60.0 mm

weight - 0.250 kg

Flare suppression results

For example I, the temperature of the PS flowing stream at a distance of 9 m from the nozzle exit along the axis of the jet was:

- using checkers PGS - 580 ... 630 K

- without the use of checkers ПГС - 1550 К

For example II, the temperature of the PS flowing stream at a distance of 5 m from the nozzle exit along the axis of the stream was:

- with the use of checkers ПГС - 650 ... 700 К

- without the use of checkers ПГС - 1550 К

Evaluation of the efficiency of flame suppression, in terms of recording the temperature of the jet at a certain distance from the nozzle exit of the solid propellant rocket along the torch axis, was chosen in relation to the operating conditions of specific missile systems.

Patented charge works as follows. The products of the combustion of the igniter charge ignite the TRT checkers and the ASG checkers. The combustion of the TRT and ASG checkers is carried out on equidistant surfaces. At the same time, due to the presence in the mixture of combustion products flowing out from the solid propellant nozzle of the thermal decomposition products of the ASG, the torch formation behind the solid propellant nozzle is practically suppressed.

The positive effect of the invention is the elimination of the "secondary torch of solid propellant rocket engines", increasing the efficiency, reliability and safety of solid propellant rocket engines for aircraft missiles and brake solid propellant rocket engines of landing platforms.

Claims (6)

1. The combined charge of a rocket engine of solid fuel with a flame-retardant effect of an expiring jet of combustion products, made in the form of a checker from solid rocket fuel and a checker from a flame-retardant composition, characterized in that the checker from a flame-retardant composition is installed at one of the ends of the checker from solid rocket fuel, and burning vault of checkers from flame-retardant composition is made taking into account the ratio
e _ASG · U _TRT = e _TRT · U _ASG ,
Where
e _ASG - burning set of checkers from flame-retardant composition;
e _TPT - burning arch of checkers from solid rocket fuel;
U _TPT - burning rate of solid rocket fuel drafts;
U _ASG is the burning rate of the checkers from the flame retardant composition, while the mass of the checkers from the flame retardant composition is made taking into account the conditions
0.05 m _TRT <m _ASG <0.10 m _TRT , where
m _TRT is the mass of solid rocket fuel drafts;
m _ASG - the mass of the checkers of the flame retardant composition. 2. The combined charge according to claim 1, characterized in that the checker of the flame-retardant composition is made in the following ratio of components, wt.%:
Potassium perchlorate 46.0-48.0 Potassium sulfate 35.0-37.0 Polyvinyl butyral 7.0-9.0 Dibutyl phthalate 3.0-4.0 Oleic Acid 1.0-2.0 Epoxy resin 1.5-2.5 Paraffin 0.5-1.5 Graphite 0.3-0.7 Polyethylene polyamine 0.3-0.7 3. The combined charge according to claim 1, characterized in that the solid rocket checker is made of ballistic solid rocket fuel or mixed solid rocket fuel. 4. The combined charge of a rocket engine of solid fuel with a flame-retardant effect of an exhausting stream of combustion products, made in the form of a multi-shell charge of solid rocket fuel, characterized in that the charge contains several checkers of a flame-retardant composition evenly spaced around the perimeter of the charge, while the burning set of checkers from a flame-retardant composition is made taking into account the ratio
e _ASG · U _TRT = e _TRT · U _ASG , where
e _ASG - burning set of checkers from flame-retardant composition;
e _TPT - burning set of drafts of solid rocket fuel;
U _TPT - burning rate of solid rocket fuel drafts;
U _ASG - burning rate of the checkers of the flame-retardant composition,
the mass of checkers from flame-retardant composition is made taking into account the conditions
0.05 m _TRT <m _ASG <0.10 m _TRT , where
m _TRT is the mass of solid rocket fuel drafts;
m _ASG - the mass of the checkers of the flame retardant composition. 5. The combined charge according to claim 4, characterized in that the checkers of the flame-retardant composition are made in the following ratio of components, wt.%:
Potassium perchlorate 46.0-48.0 Potassium sulfate 35.0-37.0 Polyvinyl butyral 7.0-9.0 Dibutyl phthalate 3.0-4.0 Oleic Acid 1.0-2.0 Epoxy resin 1.5-2.5 Paraffin 0.5-1.5 Graphite 0.3-0.7 Polyethylene polyamine 0.3-0.7 6. The combined charge according to claim 4, characterized in that the solid rocket fuel checkers are made of ballistic solid rocket fuel or mixed solid rocket fuel.

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