DE4426411A1 - Internal ballistic process for tubular weapons - Google Patents

Abstract

In a tubular weapon, H2 is supplied (21) from a H2 reservoir (20) to the combustion chamber (13) for the propellant, after it has been ignited, so that it can be chemically reacted with the propellant. Also claimed is a process similar to the above, in which a module can be fitted, e.g. a tank with a membrane which ruptures under the explosive pressure of the propellant.

Description

The invention relates to the internal ballistics of guns firing with fuel.

Previously (e.g. "Weapon technical paperback" from Rheinmetall, 7th edition 1985, from page 70), the weft development takes place in the following steps:

• - loading the ammunition
• - closing the combustion chamber
• - Ignition of the propellant charge
• - Generation of a gas pressure (combustion phase)
• - acceleration of the projectile.

There are limits to the performance of today's fuels. On the one hand the chemical composition determines the one released during combustion Energy. On the other hand, thermodynamic parameters have to be considered. So can Performance increases in fuel only over an upper limit Temperature increase. Higher propellant temperatures are undesirable to avoid excessive erosion of the projectile tubes.

The invention has for its object in a shooting with fuel Pipe weapon to increase the shooting performance while lowering the propellant gas temperatures.

This object is achieved by the features of claims 1, 4 or 5 solved.

An advantage of the invention is that the performance of the fuel is significantly increased. This is due to the hydrogenation of certain Propellant gas components. Despite the increase in performance of the fuel, the drive is reduced gas temperature because part of the hydrogen supplied does not match the Propellant reacts exothermically, but is thermodynamically stabilized and one Cooling causes. At the same time, the average molecular weight is reduced and the  Mole number of propellant gas increased. The low temperatures come on the one hand a long service life of the gun barrels. This also makes it possible powerful and accordingly high combustion temperatures winding, conventional propellant charges with correspondingly higher energetic Starting point to use.

Various embodiments of the invention are described below with reference to the Drawings explained in more detail. Show here

Fig. 1-3 differently trained tubular weapons in longitudinal section;

Fig. 4 is a diagram showing the composition of the propellant gases of an exemplary propellant charge in response to the amount of water supplied to the substance;

Fig. 5 is a diagram of the thermodynamic constants depending on the amount of hydrogen supplied.

method

The interior ballistic process for guns firing with fuel sees before that after the ignition of the fuel in the combustion chamber in the Combustion phase supplies hydrogen, which then partially with the obtained Combustion gases react chemically.

Devices

A tube weapon suitable for carrying out the aforementioned method is shown in FIG. 1. The gun 10 shown there initially consists of the conventional parts:

Closure 11
Propellant charge 12
Combustion chamber 13
Projectile tube 14
Projectile 15

In this barrel weapon 10 , the hydrogen is fed to the combustion chamber 13 from the outside. A hydrogen storage device 20 and a supply line 21 connected thereto, which opens into the combustion chamber 13, serve this purpose. The feed line 21 extends in the axial direction and is guided through the closure 11 . In deviation, the embodiment of FIG. 2 shows that the supply lines 21 can also be guided radially through the wall of the projectile tube 14 into the combustion chamber 13 . The hydrogen can be supplied with the help of external energy (e.g. mechanical pressure generators) or by using part of the energy contained in the propellant gases.

Module as an additive to the fuel

Instead of supplying the hydrogen to the combustion chamber from the outside, it is also possible to introduce the hydrogen into the combustion chamber in addition to the propellant charge during the charging process. This variant is shown in Fig. 3. There the fuel 12 is initially housed in the combustion chamber 13 . In addition, a hydrogen-containing module 30 is located in the combustion chamber 13 . After the fuel is ignited, module 30 releases the hydrogen. He then hydrogenates the propellant gases obtained from the fuel 12 in accordance with the previously described method. The module 30 could be constructed like a tank, the wall of which tears open like a membrane under the explosion pressure of the fuel 12 . Furthermore, the module 30 can be designed as a component of the ammunition (integral construction) or separately from the fuel and projectile (differential construction).

Mode of action

All fuels for guns lead to combustion gases, which are essentially always consist of the same components: water, carbon dioxide, carbon monoxide and nitrogen. These propellants depend on the recipe and are independent of Type (1-, 2- or 3-based; solid, pasty, gel-like or liquid). The quantitative proportions These gases differ depending on the type of fuel.

The oxygen-containing propellant components carbon dioxide and carbon monoxide have a high oxidation potential at the high combustion temperatures compared to hydrogen. In other words, they are easily hydrated. this is also valid for the nitrogen content.

Using the example of a modern high-performance propellant powder, Fig. 4 shows that with increasing ratio of supplied hydrogen to fuel gradually binds all the carbon dioxide and carbon monoxide with the hydrogen. At the same time, methane and water are generated:

The nitrogen in the fuel combustion gases becomes simultaneous and also exo Therin hydrogenated to ammonia:

The in-situ high-temperature hydrogenation of the propellant gases in the combustion chamber represents an increase in performance for the fuels. It is irrelevant whether the hydrogen is supplied in gaseous, liquid or solid storage. Ent the only difference is the mass ratio of hydrogen to propellant, which alone  determines the level of performance increase. Optimal mass ratios are included liquid hydrogen because of the maximum hydrogen density present here reachable.

FIG. 5 concerns the amendment of all major LPG constant with increasing the ratio of fuel to hydrogen. 10 mass% hydrogen in the propellant gas means, for example, that 100 g of hydrogen are supplied per kg of fuel. The values at 0% by mass of hydrogen in the fuel gas correspond to the parameters of the conventional, exemplary fuel and show its changes.

As can be seen from the diagram, there is an increasing proportion of free water The substance in the shot gas is thermodynamically stabilized. This leads to an ongoing ab cooling of the propellant gases, even though the hydrogenation reaction itself is exothermic.

The strong increase in heat of explosion (Q _ex ), sound speed (V _S ), pressure (p) and powder force (f) as well as the drastic drop in the gas temperature (T) can be clearly seen. Advantageously, the enormously increasing output is combined with a simultaneous and strong reduction in the gas temperature.

If we look at the course of the curve for the temperature T (influences the pipe ver wear) and the powder force f (determines the range), you can see that clear Improvements occur even with the smallest mass% of hydrogen.

Claims (5)

1.Internal ballistic method for guns firing with fuel, such that after the ignition of the fuel in the combustion chamber in the Combustion phase supplies hydrogen, which then partially with the obtained Combustion gases react chemically. 2. The method according to claim 1, wherein the hydrogen from the outside of the burner space is supplied. 3. The method of claim 1, wherein the hydrogen ent a hydrogen ent holding module is supplied, which together with the charging process the fuel is introduced into the combustion chamber and which is in the Combustion phase opens and releases the hydrogen. 4. fuel shooting tube weapon (10) having a space from the outside into the combustion (13) debouching supply line (21) for hydrogen, in order to supply to the ignition of the fuel in the combustion chamber (13) in the combustion phase hydrogen then partially reacted chemically with the combustion gases obtained. 5. Hydrogen-containing module ( 30 ) for fuel-firing Rohrwaf fen ( 10 ), which can be introduced together with the fuel ( 12 ) into the combustion chamber ( 13 ) during the charging process and is designed such that after the ignition of the fuel in the combustion chamber ( 12 ) in the combustion phase, the hydrogen contained in the module ( 30 ) is released, which then partially reacts chemically with the combustion gases obtained.