RU2486434C1 - Staroverov's shot - 5 (versions) - Google Patents

Abstract

FIELD: weapons and ammunition.

SUBSTANCE: proposed shot comprises combustible hydrogen, fuse with delay, shell filled with hydride or mix of hydrides with positive enthalpy of formation, or mix of hydrides with positive and negative enthalpy of formation at the ratio to allow release of heat at hydrides decomposition in amount sufficient for sustaining avalanche-like decomposition of said hydrides but insufficient for hydrogen self-ignition. Fuse or explosive charge is arranged at geometrical center of shot shell.

EFFECT: higher brisance.

6 cl

Description

The invention relates to civilian and, especially, to military explosive charges. The invention is applicable in all types of civilian blasting and in all military ammunition.

Volumetric explosion ammunition is known, see Internet, Wikipedia. They use an explosive reaction of a combustible substance, such as ethylene oxide, with oxygen in the air, which is mixed with air and ignited by a fuse with a time delay. However, existing ammunition on chemical reagents is not powerful enough, and nano-ammunition is quite expensive. And the presence of an internal explosive charge reduces the mass of a useful substance. The objective of the invention is the elimination of these shortcomings and the strengthening of the damaging factors of the combat charge.

A mixture of hydrogen with air has a very good explosibility, but it is problematic to store and deliver hydrogen to the place of combat use. However, you can use substances that produce hydrogen during thermal decomposition. The idea of this charge is based on this.

The charge, in addition to a separate delayed fuse, has a shell filled with a hydride or a mixture of hydrides with a positive enthalpy of formation, or a mixture of hydrides with a positive and negative enthalpy of formation in such a ratio that the heat released as a result of hydride decomposition is sufficient to maintain an avalanche-like decomposition of hydrides but insufficient for autoignition of hydrogen, and the charge also has a fuse or charge of explosive in the geometric center of the shell (hereinafter BB).

If hydrides are in a gaseous or supercritical phase state, then it is desirable that their pressure in the shell be as high as possible. Firstly, there will be more reagents in the shell, and secondly, the potential energy of the compressed gas in combination with the heat of the decomposition reaction can give its own sufficiently strong explosion. For example, if a hydrogen cylinder in the form of a shell at room temperature simply bursts from internal pressure, then the fragments and the shock wave will have greater destructive power than when a shell with an ordinary explosive bursts. We call such an explosion a “cold” explosion.

Hydrides with a positive enthalpy of formation can be silanes (mono-, di-), boranes (di-, tetra-), phosphines, germanium hydride. With negative enthalpy of formation - hydrides of beryllium, lithium, aluminum, calcium, magnesium. It is possible to use hydrides of intermetallic compounds (rare-earth elements, calcium, magnesium), as well as borohydrides, for example beryllium borohydride or double aluminum-lithium borohydride.

When choosing hydrides, it is advisable to guide the highest percentage of hydrogen in it.

The temperature of the reaction products should be selected taking into account the heat released during the operation of the explosive charge, if any (the heat of the fuse can be neglected), so that the temperature is in the range from the decomposition temperature of the most heat-resistant hydride mixture (usually 106-250 degrees C) to the temperature auto-ignition of hydrogen (700 degrees C).

SPARE OPTION. If the velocity of propagation of the reaction front in a confined space in a given medium (by analogy with explosives is called the “detonation velocity”) is below the limit of requirements for explosives (quite tentatively, this lower limit in this case can be designated as the speed of sound in air, i.e. 350 m / s on average), then two fallback options are possible. First, the shell strength is selected from the condition of its destruction at an internal pressure equal to 80-95% of the maximum pressure at the end of the reaction. And in this case, the shell after some time (fractions of seconds or even seconds) self-destructs, scattering fragments and causing a shock wave.

The second - the shell is made a little stronger (and heavier) and can withstand the maximum pressure of the reaction products. That is, she herself will not be destroyed. Then, after the end of the reaction, it is cut by a perforating linear cumulative charge located outside or inside the shell. The shape of the cut can be chosen in the most diverse way: for high-explosive charges in a bomb-shaped shell, a cut across the horizontal plane is advantageous, in which case the main energy of the shock wave will be directed to the sides. A fragmentation of ammunition is advantageous to cut into small parts.

One drawback of this charge should be noted - a charge with gaseous hydride is desirable (but not necessary) to store and use at a temperature higher than the critical temperature of the reagents included in it. For diboran, the critical temperature is 16.7 degrees C, and for monosilane it is -3 degrees C. That is, you need to store and apply the charge with diborane at room temperature, for which it may be required carefully in the winter or when flying on an airplane at high altitude heat, otherwise a liquid phase of the reagent may form in the shell. However, this will slightly reduce the charge power, since the atomized liquid hydride, firstly, will immediately evaporate, and secondly, it will explode no worse than in an aerosol state.

On the shell, it is desirable to provide for the presence of micro notches or zone hardening for uniform crushing, and therefore, for uniform dispersion of hydrogen in the atmosphere.

It should be noted non-obvious, but very useful quality of this charge is a very strong fragmentation effect. In the example below, the temperature of the reaction products is 420 degrees C, and the specific energy release is only 1.27 kJ / g. It would seem that such parameters are not able to give destructive power to the fragments and create a strong shock wave. But the fact is that at the time of rupture of the shell, it will contain only solid finely dispersed reaction products and pure hydrogen at a pressure of about 500 atm (or even more). And the speed of sound in hydrogen at this temperature is 2050 m / s, which can give the fragments an initial speed of 1900 m / s. Of course, no one has canceled the energy conservation law - the kinetic energy of fragments and a shock wave cannot be greater (moreover, taking into account the efficiency) of the compressed gas energy and the hydride decomposition energy.

That is, such a charge, like the usual charge of a volume explosion, explodes twice. But, if in the ordinary or in the nanosized charge the first explosion is practically safe, then in the given charge a field of fragments is formed at a speed of 1900 m / s, then a strong shock wave created by expanding hydrogen, and then the second explosion is volumetric. Moreover, it is not even clear which explosion will be stronger in pressure at the front of the shock wave — the first or second. That is, such a charge has a triple striking ability: the first “cold” explosion is its shock wave, high-energy fragments and a volume explosion.

There are some requirements for the shell material: of course, it must have high tensile strength and the absence of defects, but, in addition, it should not have too much ductility. Otherwise, part of the energy of the first explosion will be uselessly spent on its plastic deformation.

It is useful to use the double nature of the explosion. Suppose we need to make the greatest destruction of some buildings (for military or civilian purposes) - houses, bridges, overlapping pillboxes. Knowing the nature of the structures, it is possible to calculate (and check with a vibrator practically) the resonant frequency of the walls or ceilings of these buildings, or the bridge and adjust the time difference between the first explosion and the second so that it is a multiple of the period of natural vibrations of the structure. Then the first explosion will swing the structure, then it will bend in the opposite direction, and then, during the deflection of the structure to the original side, a second shock wave will come, which will destroy the structure.

Such a charge, as an anti-personnel weapon, such as a hand grenade, will have another useful feature. Suppose the first grenade explosion occurred on the surface of the earth, and the enemy’s manpower, taking refuge in the folds of the terrain or in the trenches, did not suffer losses. But after a “cold” explosion, a cloud of hydrogen-air mixture, if it was not set on fire by a random source of fire, will fly to a certain height (say 3-5 meters), and the shock wave from the second explosion will be directed at some angle from top to bottom and can hit the enemy in the trenches.

To use such a triple striking ability of a given charge, a fuse with a delay must be retuneable with sufficient accuracy.

Example: consider a mixture of two components - diborane M = 27.67, ent = + 38.5, percentage of hydrogen 21.9%, specific heat +1.39 kJ / g, and monosilane M = 32.12, ent = +34.7, the percentage of hydrogen 12.5%, specific heat + 1.08 kJ / g.

We take the initial charge temperature of 20 degrees C and the desired temperature of the reaction products 420 degrees C. The specific heat of the products of both reactions at a constant pressure in this temperature range is approximately 3.94 j / g for diborane and 2.43 j / g for monosilane. We determine the ratio of reagents, for which we take the amount of diborane as “x” and compose the energy balance of the reaction:

1000 / 1.39x + (1-x) 1.08 / = 400 / 3.94x + (1-x) 2.43 / or 2.5 (0.31x + 1.08) = 2.43 + 1.51x or 0.775x + 2.7 = 2.43 + 1.51x or -0.735x = -0.27 or x = 0.367

that is, the charge should contain 36.7% of diborane and, naturally, 63.3% of monosilane.

It should be noted that the decomposition reaction of diborane at constant pressure would give a temperature of 350 degrees C, and the decomposition reaction of monosilane would be 445 degrees C, and if the volume diborane was 440 degrees C and for monosilane 550 degrees C, which would also be much lower than the ignition temperature . This means that one could make a charge of pure diborane or monosilane.

However, this temperature should not be overestimated, since the efficiency explosion, as a kind of heat engine, falls with increasing initial temperature of the combustible mixture. And the combustible mixture in this example is, of course, the hydrogen formed, as well as the released boron and silicon, which during the explosion can also participate in the reaction with atmospheric oxygen.

If the charge contains only a fuse and does not contain an internal explosive charge, then the shell strength should not be chosen too large, since the increase in pressure in it due to the reaction will not be very large - approximately 5 times in the considered example. That is, if the initial pressure in the shell was 100 atm, then it should be destroyed, for example, at 400 atm.

The charge works like this: hydrogen, boron and silicon dissipate in the air with a strong “cold” explosion and form fragments at a speed of 1900 m / s, and then the fuse delays the hydrogen-air mixture with a delay and it detonates.

Claims (6)

1. A charge containing a combustible substance and a fuse with a delay, characterized in that it contains a shell filled with a hydride or a mixture of hydrides with a positive enthalpy of formation, or a mixture of hydrides with a positive and negative enthalpy of formation in such a ratio that the heat released from the decomposition of hydrides was sufficient to maintain an avalanche-like decomposition of hydrides, but insufficient for self-ignition of hydrogen, and the charge has a fuse in the geometric center of the shell or an explosive charge wow substance. 2. The charge according to claim 1, characterized in that the charge used hydrides of lithium or aluminum, or beryllium, or calcium, or magnesium, or germanium, or intermetallic hydrides, or borohydrides, or double borohydrides, or boranes, or silanes, or phosphines. 3. The charge according to claim 1, characterized in that it contains 36.7% diborane and 63.3% monosilane. 4. The charge according to claim 1, characterized in that the fuse with a delay has an adjustable delay time. 5. The charge according to claim 1, characterized in that the shell strength is 80-95% of the maximum internal pressure at the end of the reaction. 6. The charge according to claim 1, characterized in that it has an explosive or cumulative charge inside or outside the shell that can pierce or cut through the shell.