RU2345283C1 - Method of rocket engine solid fuel utilisation - Google Patents

Abstract

FIELD: heating, fuel.

SUBSTANCE: invention relates to the spent rocket fuel processing technologies. The method of rocket solid fuel utilisation under field conditions includes the fuel burning off from the engine housing. The circular groove is made in the front bottom of the utilised engine from the condition that the bottom is opened along circular relief under the pressure in housing 5…25 kgf/cm². In addition the outer diameter of circular groove (D) is derived taking into account the condition:

where F_cr - area of critical cross section in rocket engine operating on solid fuel, P_op - operating pressure in rocket engine under F_cr, P_up - pressure in the utilised rocket engine operating on solid fuel if F_cr and additional opening with D diameter in the front bottom are available, ν - is an indicator of propellant burning velocity in power law. The rocket engine is placed in the grounded pit and provided with a line to supply pulse to triggering pyrocartridge and engine is started remotely from the shelter. In addition the pit depth is no less than two calibers of the utilized rocket engine operating on solid fuel.

EFFECT: simple and safe utilisation method.

3 dwg, 1 ex

Description

The invention relates to the field of rocket technology and can be used in the disposal of solid propellant rocket engines (solid propellant rocket engines), preferably small and medium calibers.

A known method of utilization of solid propellant solid propellant solid propellant solid propellant (TRT) charge according to patent RU 2064659, which consists in the mechanical grinding of the charge, followed by dissolution of ammonium perchlorate (PCA) - the main component of TRT using sodium hydroxide. The specified method is characterized by high complexity and duration.

There is also a known method for utilization of solid propellant solid propellant by burning a solid propellant charge connected to the body according to patent RU 2021560, according to which the charge channel is filled with refrigerant, the utilized solid propellant is installed with the nozzle up and the solid propellant is started up and the solid propellant is burned out of the housing. The method according to patent RU 2021560, IPC F23G 7/00, claimed 15.04.93, published 10.15.94 adopted by the authors as a prototype.

The disadvantages of the prototype method are the high financial and economic costs in its implementation associated with the preparation for transportation, sometimes very long and long to the places of disposal (landfills, stands). The process of delivery to equipped disposal sites is not always safe, especially in the case of transportation of solid propellant solid waste, with expired (extended) life.

The technical task of the patented invention is the development of a simple, with increased reliability and safety of the method of disposal of solid propellant solid propellant (by burning TRT from the housing) of small and medium calibers (diameter up to 0.5 m, weight up to 500 kg) in the field (usually near technical positions operational rocket systems or arsenals), which provides a reduction in the negative impact on the environment with reduced financial costs.

The technical result of the invention is to develop a method for utilization of solid propellant by burning solid rocket fuel charge from the solid propellant rocket in the field, while in the front bottom of the solid propellant rocket, ring weakening is performed before the charge is burned - a groove from the opening condition of the bottom by ring weakening at a pressure in the housing of 5 ÷ 25 kgf / cm ² , the outer diameter of which (D) corresponds to the ratio

where F _cr - the critical section area of the solid propellant nozzle;

R _RD - working pressure in the housing of the solid propellant rocket engine at F _cr ;

R _urd - pressure in the housing of the solid propellant solid propellant in the presence of F _cr and an additional hole F _up in the front bottom of the engine;

ν is the exponent in the power law of the burning rate of solid rocket fuel at ambient temperature during the solid propellant waste disposal.

The disposed solid propellant rocket is placed in a space buried in the ground - a pit, the depth of which is at least two calibers of the solid propellant solid propellant rocket, equip the disposable solid propellant rocket motor with a pulse supply line to the launch igniter and remotely start the solid propellant rocket motor from a safe distance.

The essence of the invention is to provide, when a TRT is burned with an additional hole, the front cover of the utilized solid propellant rocket, which allows, on the one hand, to provide a lowered, safe (eliminating the destruction of the solid propellant solid propellant) pressure in the combustion chamber (CS), on the other hand, due to critical expiration of products of combustion (PS) from CS, mainly, afterburning of nitrogen oxides, carbon and other components of TS TPT in CS, which helps to reduce the negative impact of the latter during TR burning (Fire tests) on the ecology of the environment. In this case, the operation of the utilized solid propellant is directly carried out at a pressure in the COP 3 ... 5 (or less) times less (Fig. 1) provided for its operation. The critical conditions for the expiration of the PS of solid rocket fuel (TRT) are ensured by the implementation in the front bottom of the solid propellant rocket engine of an additional hole of area F _up , obtained due to an annular groove (attenuation) with an outer diameter D. The ratio for D is obtained from the following considerations.

For the quasistationary mode of operation of the solid propellant rocket engine the following is true [Shapiro Ya.M., Mazint G.Yu., Prudnikov N.E., Theory of a solid propellant rocket engine, M., 1966, p. 69]:

where S is the area of the burning surface of the charge;

u = u ₁ p ^v is the rate of combustion of the TRT;

αA is the expiration coefficient;

F _cr - the critical section area of the solid propellant nozzle;

P is the pressure in the solid propellant solid propellant rocket;

γ is the density of TRT.

In view of the foregoing, for solid propellant rocket motors without an additional hole (F _to ), we have

For solid propellant rocket motors with an additional hole, we have

In the relations [2], [3]:

R _RD - working pressure in the solid propellant rocket without an additional hole;

R _urd - working pressure in the utilized solid propellant solid propellant with an additional hole;

From the relations [2], [3], [4] it follows

In the case of performing an annular groove (attenuation), given that

we have

where π = 3, 14, D is the diameter of the annular groove - attenuation along the outer diameter.

In accordance with the technical task, in the patented technical solution, reliability and safety during disposal and minimally harmful impact on the environment should be ensured.

Reliability and safety when disposing of solid propellant solid propellant by the proposed method is achieved (Fig. 2) due to the maximum possible reduction of the operating pressure in the COP of the solid propellant solid propellant (25 kgf / cm ² or less) to the level of a stable lower limit for combustion of solid propellant fuel, taking into account the tightness of the engine (for due to the implementation of the ring groove - weakening (8) in the front bottom (7) without depressurization of the engine) until the solid fuel charge is burned (3), as well as a significant decrease in the pressure level in the solid propellant rocket engine, and the harmful minimal impact on the environment environment - by ensuring efficient afterburning of substrates in the SC of the utilized solid propellant rocket during critical expiration of substrates.

The provision in the process of disposal (burning TRT) in the front bottom of the solid propellant rocket engine of an opening of area F _to also completely or substantially “nullifies” the traction along the axis of the solid propellant solid propellant to be eliminated and thereby eliminate or significantly reduce the probability of failure (Fig. 3) of the solid propellant solid propellant (11) ) from the place of attachment of lodgements (12), clamps (13), and the destruction of the solid propellant rocket during the fire test during disposal. Deepening the utilized solid propellant rocket into the soil to a depth of not less than 2 calibres practically excludes the solid propellant rocket from escaping when the latter is removed from the mount. Providing a remote supply (14) of impulse to the igniter contributes to the safety of disposal.

The invention is illustrated in the drawings.

Figure 1 The diagram "pressure-time"

P is the pressure;

τ is the time;

1 - for “combat” solid propellant rocket engines;

2 - for utilized solid propellant solid propellant.

Figure 2 The design of the utilized solid propellant rocket engine prepared for burning fuel

3 - solid fuel charge;

4 - the body of the solid propellant rocket engine;

5 - the back bottom;

6 - nozzle;

7 - front bottom;

8 - annular groove;

9 - ignition unit;

10 - squib.

Figure 3 Installation diagram of a disposable solid propellant solid propellant rocket for burning TRT (fire burning)

11 - solid propellant rocket engine;

12 - lodgement;

13 - a collar;

14 - line supply electric pulse to the squib.

An example implementation of the method.

The starting solid propellant rocket with a solidly charged TRT charge was disposed of. The charge mass is 480 kg, the solid propellant caliber is 0.5 m, ν = 0.35, F _cr = 266 cm ² , P _rd = 75 kgf / cm ² . An annular groove was performed in the front cover of the solid propellant rocket motor - attenuation, which, when opening the cover along the groove, provided an additional hole F _to calculated by the ratio [5]:

The solid propellant rocket motor was placed (Fig. 3) in a pit-depth buried in a pound, providing a depth of penetration relative to the axis of the solid propellant rocket of at least two solid propellant rocket motors, providing at least 7 calibers of solid rocket motor from the front and rear bottoms of solid rocket motor (11). The impulse (14) was supplied remotely from the buried shelter to the RDTT launch squib. The charge was burned off satisfactorily (completely, up to the walls of the CS) without destruction of the solid propellant rocket engine.

Claims (1)

A method of utilizing a solid propellant rocket engine in the field, including burning fuel from the engine casing, characterized in that an annular groove is performed in the front bottom of the utilized engine — attenuation from the condition of opening the bottom by annular weakening at a pressure in the housing of 5 ... 25 kgf / cm ² , while the outer diameter of the annular groove (D) provide, subject to the conditions:

where F _cr - the critical section area of the solid propellant nozzle,
R _RD - working pressure in the housing of the solid propellant rocket engine at F _cr ,
R _urd is the pressure in the housing of the solid propellant solid propellant in the presence of F _cr and an additional hole in the front bottom of the engine with a diameter of D,
ν - exponent in the power law of the burning rate of solid rocket fuel,
the rocket engine is placed in a pit buried in the ground, equipped with a pulse supply line to the launch squib and remote start the engine from the shelter, while the depth of the pit is at least 2 calibers of the solid propellant rocket propeller.

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