RU52939U1 - DETONATION CAMERA - Google Patents

Abstract

The detonation chamber refers to pulsating jet engines with resonant combustion chambers. The objective of the utility model is to increase the reliability of the detonation chamber. The technical result of the proposed detonation chamber is to increase the likelihood of organizing a continuous detonation process, as well as in the reliable separation of the supplied fuel components and their detonation products. The task is achieved in that the detonation chamber contains a fuel supply system located in a single housing, a supersonic nozzle and a coaxial cavity located with it, facing the open end towards the outflow of detonation products. In this case, the inner surface of the resonator is made in the form of a cone, and the fuel supply system is an Laval ring nozzle made in the device body and facing the resonator. The traction force is created due to the interaction of the detonation wave with the inner conical surface of the resonator 2, as well as due to the reactive force formed by the supersonic gas stream flowing through the nozzle. The total thrust impulse of the detonation chamber is directly proportional to the pulsation frequency and the pressure on the walls of the resonator 2. By changing these parameters, it is possible to control the thrust vector module. The developed detonation chamber is characterized by: the possibility of organizing a continuous detonation process, high reliability due to the separation of the areas of the supplied fuel components and their detonation products; smaller geometrical dimensions of the resonator; lack of initiation and purge systems. The proposed design of the detonation chamber allows you to get the maximum frequency of detonation processes.

Description

The utility model relates to pulsating jet engines with resonant combustion chambers.

Known pulsating detonation combustion engines, in which the detonation chamber contains a flat or special shape of the front wall, turning into a cylindrical shape, and the opposite (rear) end of the chamber is open and equipped with a conventional nozzle such as a rocket engine nozzle (see R.I. Kurziner. Jet engines for high supersonic flight speeds (Moscow: Mashinostroenie, 1989, pp. 214-215).

Known detonation chambers designed for a more complete (shock) afterburning of the combustion products of rocket fuel and provide the most favorable conditions for the occurrence of detonation. One of the options for the structural embodiment of this effect is the "Jet nozzle of a pulsating detonation combustion engine with a central body" (RF patent No. 2066779, IPC F 02 K 7/04, 1996). It contains a semi-closed cavity located in the central body of the engine chamber, a supply unit for the working fluid, as well as nozzles and a device for generating shock waves. In this case, the nozzles are made in the form of a supercritical part of the Laval nozzle, the inner surface of which is a continuation of the surface of a semi-closed cavity, and the device for creating shock waves is in the form of a hollow streamlined body, the supply of the working fluid is in the form of an annular gap formed by the engine chamber body and the central body .

When the working fluid enters through the supply unit to the detonation chamber, all filling takes place. As the chamber fills, it is blocked by a plane supersonic stream converging to the center. At the same time, part of the working fluid enters the nozzle. In the process of filling a semi-enclosed cavity, the pressure and temperature in it increase stepwise, which leads to the formation of detonation. At the same time, a part of a planar supersonic jet converging toward the center, which did not participate in the working process taking place in the detonation chambers, rushes into the nozzle and flows onto a device for generating shock waves. A system of shock waves is formed, which converges at the focus of the detonation chamber and in which there is a sharp increase in temperature and pressure. In turn, this leads to detonation afterburning of the working fluid in the nozzle and its further outflow.

However, this device is characterized by a significant drawback, consisting in the low reliability of the device, associated with a low probability of detonation. This disadvantage is eliminated in those devices in which the additional energy supply is necessary for the detonation process to occur, for example, RF patent No. 20548 “Device for the detonation combustion of fuel mixtures”, 2001. A piezoelectric type pressure sensor is installed in the region of the center of the bottom of the resonator, connected to the initiator through an amplification-converting device.

The closest in technical essence and the achieved technical effect to the proposed technical solution is "Pulse detonation engine having an aerodynamic valve" (US patent No. 6584765, IPC F 02 K 7/02, 2004.). It combines both effects: introducing additional energy by introducing an electric candle and supplying the fuel components in such a way that they intersect at the focus located on the camera axis.

However, this device is also characterized by disadvantages of

- supply of separate fuel components to the detonation chamber (in recent years, leading experts in the field of detonation engines have come to the conclusion that it is necessary to supply the finished fuel-air mixture to the chamber);

- the impossibility of organizing a continuous detonation process, because the processes taking place in the detonation chamber are accompanied by the intersection of the regions of the supplied fuel components and the products of their detonation;

- the dependence of the frequency of detonation processes on the frequency of operation of the electric candle and which can excite the detonation process only if there is a fresh portion of the fuel-air mixture, which is difficult to do without organizing a purge system.

To eliminate these shortcomings, it is necessary to provide the most favorable conditions for the occurrence and maintenance of detonation.

The objective of the utility model is to increase the reliability of the detonation chamber.

The technical result of the proposed detonation chamber is to increase the likelihood of organizing a continuous detonation process, as well as in the reliable separation of the supplied fuel components and their detonation products.

The task is achieved in that the detonation chamber contains a fuel supply system located in a single housing, a supersonic nozzle and a resonator located coaxially with the open end facing the outflow side of the products

detonation. In this case, the inner surface of the resonator is made in the form of a cone, and the fuel supply system is an Laval ring nozzle made in the device body and facing the resonator.

The drawing shows a detonation chamber,

where: 1 - device for supplying a fuel-air mixture;

2 - resonator;

3 - supersonic nozzle;

4 - annular Laval nozzle;

5 - housing.

The detonation chamber consists of consists of a device for supplying a fuel-air mixture 1, a resonator 2 and a supersonic nozzle 3, assembled in a single device.

The fuel-air mixture supply device 1 is designed to accelerate the working mixture to supersonic speeds (M> 1) and direct it into the cavity 2. It is an Laval ring nozzle 4 made in the body 5 of the detonation chamber 2.

The resonator 2 is designed to create shock waves and excite the detonation process. It has a conical shape, closed at one end and facing the open end towards the nozzle 3.

The supersonic nozzle 3 is designed to disperse gases (detonation products) flowing out of the cavity of the resonator and creating engine thrust.

The detonation chamber operates as follows.

The fuel-air mixture flowing through the Laval 4 nozzle 4 acquires supersonic speed. Accelerated to a supersonic speed, the working mixture flows onto the internal cavity of resonator 2. Reflecting from the inner surface of resonator 2, reflected shock waves form

These waves are focused on the axis of the device, forming a standing focusing center line, the length of which X is determined by the expression

X = L cosα,

where: L is the length of the conical part of the resonator 2;

α is the half-angle of the cavity 2.

In this case, a sharp increase in temperature and pressure occurs on the focusing center line (Springer effect), which leads to the appearance of a detonation wave in the working mixture and its detonation ignition. The pressure pulsation in the resonator 2 depends on the depth of the resonator and is determined only by the number M of the incident jet.

The oscillation frequency is determined by the depth of the resonator L and the speed of wave propagation in it.

Thus, a high-frequency oscillatory process is excited with the formation of shock and detonation waves.

Improving the efficiency of the device lies in the fact that during detonation combustion of the fuel mixture, the temperature and pressure are much higher than similar parameters obtained by conventional combustion of the same amount of the working mixture. Consequently, the work done by the detonation products will be more than the work done by the combustion products.

Detonation products flowing out of the cavity of the resonator, through a supersonic nozzle 3, rush to its exit and create engine thrust.

The traction force is created due to the interaction of the detonation wave with the inner conical surface of the resonator 2, as well as due to the reactive force formed by the supersonic gas stream flowing through the nozzle. The total thrust impulse of the detonation chamber is directly proportional to the pulsation frequency and the pressure on the walls of the resonator 2. By changing these parameters, it is possible to control the thrust vector module.

The developed detonation chamber is characterized by: the possibility of organizing a continuous detonation process, high reliability due to the separation of the areas of the supplied fuel components and their detonation products; smaller geometrical dimensions of the resonator; lack of initiation and purge systems.

The proposed design of the detonation chamber allows you to get the maximum frequency of detonation processes.

Claims (1)

A detonation chamber containing a fuel supply system located in a single housing, a supersonic nozzle and a cavity located coaxially with it, facing the open end towards the outflow of detonation products, characterized in that the inner surface of the resonator is made in the form of a cone, and the fuel supply system is an Laval ring nozzle, made in the housing of the device and facing toward the resonator.