RU2451202C1 - Method of augmenting liquid-propellant rocket engine thrust and liquid-propellant rocket engine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed method comprises using gas turbine driven by vapor of one of fuel components generated in combustion chamber cooling loop and consists in increasing gas temperature upstream of turbine. Note here that proportioned amount of another fuel component is injected into vapor flow for mix produced to be fired. Proposed engine comprises combustion chamber with cooling circuit and injector head, fuel and oxidiser pumps, and turbine with its inlet communicated with combustion chamber cooling circuit. In compliance with this invention, device made up of diffuser and injector are arranged in pipeline communicating chamber cooling circuit and turbine. Besides, said device includes igniter and flame stabiliser.

EFFECT: expanded operating performances.

3 cl, 1 dwg

Description

The present invention relates to the field of rocket propulsion, focused on space transport systems.

One of the requirements for a liquid propellant rocket engine (LRE) is the requirement to provide the ability to control the magnitude of the thrust during the flight of the rocket, including upward (i.e., forcing). The process of changing the thrust of the rocket engine takes place through a change in fuel consumption through the combustion chamber, which, in turn, is achieved by changing the pressure of the fuel supply. The latter is achieved for liquid propellant engines equipped with a turbopump fuel supply system by changing the rotor speed of the turbopump assembly (TNA) by changing the turbine power.

There are two known methods for changing the power of a TNA turbine when regulating the thrust of a rocket engine: by changing the temperature of the gas in front of the turbine and by changing the mass flow of gas.

According to the first method, engines are usually controlled, which include a two-component gas generator to generate a turbine working fluid (see the scheme in the book of T. M. Melkumov et al. "Rocket Engines", M .: "Mechanical Engineering", 1968, p. 11, Fig. 1.5), and according to the second scheme - engines in which the turbine working body is produced by evaporation and heating of one of the components of rocket fuel in the cooling path (jacket) of the combustion chamber (see the diagram of the American rocket engine RL-10 (RL-10), Encyclopedia "Cosmonautics", M .: "Soviet Encyclopedia", 1985, p. 337 - prototypes P).

The proposed new method of forcing thrust rocket engines is applicable to rocket engines in which the working fluid of a turbine (or one of the turbines, for example, a rocket engine according to RF patent No. 2352804 is a prototype) is produced by evaporation of one of the components of rocket fuel. A feature of the liquid propellant rocket engine adopted for the prototype is that the temperature of the vapor of the fuel component vaporized in the jacket of the combustion chamber formed by the deterministic heat removal value (for a fixed combination of the heat-transfer surface area and the mass flow rate of the fuel component through the cooling path) is low (450-500K). This temperature is much lower than the permissible level under the condition of ensuring the turbine operability (up to 1200K) and, which is essential, can not be changed during operation of the engine by simple means of regulation. In view of the foregoing, the expenditure method for regulating the power of such a turbine (by regulating the bypass of a part of the gas past the turbine) is a forced and practically the only available method. Hence the disadvantages of this method: a decrease in the nominal power of the turbine (in proportion to the proportion of gas bypassed by the turbine) and the inability to realize a high level of forcing in the case of

an emergency situation during the launch or flight of a rocket (for example, if one engine fails in a four-engine installation when a rocket starts, in order to urgently withdraw the last from the launch facilities, it is necessary to force each of the remaining three engines to the level of 133% of the nominal thrust).

The aim of the present invention is to significantly expand the thrust boosting range of a liquid propellant rocket engine while increasing the turbine's rated power.

This goal is achieved in that a thrust-boosting method for a liquid propellant rocket engine containing a gas turbine driven by steam of one of the fuel components formed in the cooling path of the combustion chamber, based on increasing the temperature of the gas in front of the turbine, according to the invention, into the steam stream before feeding it a metered amount of another fuel component is injected onto the turbine and the resulting fuel mixture is ignited.

At the same time, it becomes possible to eliminate the parasitic bypass of a part of the gas past the turbine in the nominal engine operating mode, and also significantly expand the boosting range by increasing the upper limit of the gas temperature in front of the turbine to 1200K instead of (450-500) K. The latter advantage is also realized for engines that have two turbines, one of which is fed with gas produced by a two-component gas generator, and the other with steam from one of the fuel components (for example, the LRE according to patent No. 2352804).

This method is particularly easy and effective can be implemented in a liquid-propellant rocket engine containing a combustion chamber with a cooling path and a nozzle head, a fuel pump, an oxidizer pump and a turbine communicated by an inlet with a cooled path of the combustion chamber, while in a pipeline connecting the cooling path of the chamber and a turbine, a device comprising a diffuser and a nozzle is mounted. The device contains an igniter and a flame stabilizer, in which, in accordance with the circuit diagram, it is possible to select and inject the second component without the need for an additional pump to increase the pressure of the injected component (for example, on the engine according to patent No. 2352804). The essence of the proposed method and its implementation on the engine is illustrated by the diagram in figure 1, where the following notation:

1 - oxidizer supply line;

2 - fuel supply line;

3 - oxidizer pump;

4 - fuel pump;

5 - oxidizing turbine;

6 - recovery turbine;

7 - oxidizing gas generator;

8 - regulator of fuel consumption in the gas generator;

9 - a fuel throttle;

10 - combustion chamber;

11 - a pipeline for supplying fuel vapor to a recovery turbine;

12 - diffuser;

13 - nozzle (sprayer);

14 - flame stabilizer;

15 - igniter;

16 - pipeline for the selection of oxidizing gas for injection into the stream of fuel vapor;

17 - start-up valve.

The engine using the proposed method of forcing is as follows.

After starting, the engine operates in the main mode and can be adjusted by the ratio of components using the throttle 9, as well as by thrust in a small range using the flow regulator 8 by changing the ratio of components in the gas generator 7, which, in turn, changes the temperature of the gas supplied to oxidizing turbine 5. Since turbine 5 runs on gas with a high content of free oxygen, there is a limit on the maximum the gas temperature (typically at 850-900K level). In this regard, the range of possible engine boosting with the help of controller 8 is limited by the indicated temperature. When the thrust is forced to an extremely high level, the valve 17 opens, and the oxidizing gas passes through the pipe 16 to the device (afterburner) installed in the pipe 11, where, being sprayed in the diffuser 12 using the nozzle 13, it is mixed with fuel vapor, forming a fuel mixture, which spontaneously ignites or is forced to be ignited by means of an igniter 15. The flame is stabilized by a flame stabilizer 14. The productivity of the nozzle 13 is adjusted to a certain flow rate of oxidizing gas, based on the required It is necessary to obtain the required power increase of the turbine 6 during forcing. If it is necessary to stop forcing, the component supply is cut off through the pipeline 16 by closing the valve 17. The engine returns to the initial operation mode.

If it is necessary to use a liquid oxidizer to implement this method of forcing, the pipeline 16, instead of connecting to the outlet pipe of the gas generator 7, is connected to the pipeline after the oxidizer pump 3. Thus, the relatively simple structural means solve the problem of boosting the thrust of the rocket engine with a positive effect - a significant expansion of the range possible boost in relation to the prototype while increasing the rated power of the turbines. The use of this invention will improve the safety of launch vehicles at launch and in flight due to the implementation of the ideology of hot standby thrust of a multi-unit propulsion system (this ideology assumes a high level of forcing of properly functioning engines in case of failure of one or more engines).

Claims (3)

1. A method of forcing along a thrust of a liquid propellant rocket engine containing a gas turbine driven by steam of one of the fuel components formed in the cooling path of the combustion chamber, based on an increase in the temperature of the gas in front of the turbine, characterized in that it is introduced into the steam stream before it is fed to the turbine they inject a metered amount of another fuel component and ignite the resulting fuel mixture. 2. A liquid rocket engine for implementing the method according to claim 1, comprising a combustion chamber with a cooling path and a nozzle head, a fuel pump, an oxidizer pump and a turbine communicated by an inlet with a cooled combustion chamber path, characterized in that in a pipe connecting the chamber cooling path and a turbine, a device comprising a diffuser and a nozzle is mounted. 3. The liquid rocket engine according to claim 2, characterized in that the device is mounted in a pipeline connecting the cooling path of the chamber and the turbine, the device contains an ignitor and a flame stabilizer.