Shock wave of various ammunition: radius of guaranteed destruction

Modern body armor can provide reliable protection to a soldier not only from bullets fired from small arms weapons certain calibers, but also from fragments resulting from the explosion of shells and mines.

Meanwhile, in the case of the latter, the greatest danger to manpower is posed not so much by fragments as by high-explosive effects, from which body armor is not capable of protecting, regardless of its class.

True, it is worth noting here that the radius of damage of the shock wave, which can kill or cause concussion, is much smaller than that of fragments. Its range is directly related to the mass and composition of the explosive in a particular ammunition.

Typically, the radius of damage from the shock wave is equal to the cube root of the TNT equivalent of the explosion power. Consequently, to double the radius of destruction by a shock wave, the amount of explosive in the projectile must be increased eightfold.

Now about the ammunition. The smallest of those that can kill a fighter with a blast wave is the F-1 grenade, widespread in the post-Soviet space, which contains 60 grams of explosives.

Such ammunition is guaranteed to kill with a shock wave within a radius of 0,63 meters. At the same time, the high-explosive effect of the F-1 is not lethal even at a distance of 2,5 meters from the epicenter of the explosion. At the same time, concussion can be avoided at a distance of 5,5 meters.

In turn, the RGD-5 grenade is guaranteed to kill with a shock wave at a distance of 0,81 meters.

The 82-mm mortar mine, widely used during air defense, can contain from 413 to 450 grams of explosive. In this case, the high-explosive effect is guaranteed to be fatal to manpower within a radius of 1,7 meters. Such a mine (we are talking about a shock wave) at a distance of 7 meters will not kill, but concussion can be avoided by being 12 meters from the epicenter.

Regarding the projectile for 122-mm howitzers under the symbol OF-56, which is filled with 4050 gr. hexal, its shock wave will definitely kill at a distance of 4,2 meters. At the same time, the high-explosive effect of this ammunition becomes non-lethal at a distance of 17 meters from the epicenter of the explosion, and concussion can be avoided at a distance of 28,5 m.

Comments

[Nexcom]

Well, how about the True Life channel, you can watch it yourself.....

[Mavrikiy]

In turn, the RGD-5 grenade is guaranteed to kill with a shock wave at a distance of 0,81 meters.

Normally, at a distance of 0,81 m you are dead, but at 0,82 m you will still serve! To make your conclusions more accurate, try rounding.

[Hitriy Zhuk]

Quote: Mavrikiy

and at 0,82 m - you will still serve!

But at 0.82 it is no longer guaranteed. If the fragments fly by.
Well, like not 100% but 99.5%.

[bk316]

Why didn’t the author continue?
ODAB -500
FAB -3000
It would be very useful to know what this is
ONLY 30 and 39 meters respectively

Useful to straighten the minds of some VO readers.
Otherwise, they argue with foam at the mouth that ODAB is practically tactical nuclear weapons.
But it costs the Russian Federation nothing to level the cities of ODAB and it’s all a matter of agreements.

So for reference, for a 6 km by 6 km square of such bombs you will need DTHERE ARE THOUSANDS
And there are only NINE low-power atomic ones (20 kt) (the radius of lethal damage by the shock wave is 1 km)

[alebdun2000]

So that’s true, but ODAB and FABs are also used pointwise, almost like Krasnopol. Their correction is quite accurate. So 10K is not necessary, and there are no VSU headphones in every meter of six sq. km.

[hammer it]

Quote: bk316

Otherwise, they argue with foam at the mouth that ODAB is practically tactical nuclear weapons.

They didn’t come up with this themselves, the colonel general suggested it to them.

[fiv]

And vodka kills only through direct contact. And this is not always the case.

[Hitriy Zhuk]

Consequently, to double the radius of destruction by a shock wave, the amount of explosive in the projectile must be increased eightfold.

What if we make a bomb, say not a cylinder but a pancake/ring?
Or try directed explosions?

[cpls22]

Apparently, this list of distances refers to direct exposure if a person is caught by a blast wave in an open space. In this situation, fragments are difficult to avoid. But how does a blast wave behave as it spreads across rough terrain, how deep does it fly into a trench, does it go around trees? How does it spread when a projectile hits the ground, does a helmet protect you from it? Here are some interesting details that could help you survive. But for this it is not enough to retell the reference book in an electronic voice.

[fiv]

Like any wave propagation taking into account the properties of the medium

[cpls22]

Quote: fiv

Like any wave propagation taking into account the properties of the medium

I read somewhere that a shock wave is not an ordinary wave, because its speed is greater than the speed of other acoustic waves characteristic of a given medium. And the propagation of shock waves at the boundaries of media is especially interesting from the point of view of the impact on targets. An example comes to mind from some fiction, where a figure cut out with a knife on a TNT block gives a hole in a sheet of iron, but the place of close contact between the iron and the block remains unpierced. I don't know if this is true.

[Grossvater]

Quote: bk316

Why didn’t the author continue?
ODAB -500
FAB -3000
It would be very useful to know what this is
ONLY 30 and 39 meters respectively

And, I’m embarrassed to ask, where does the firewood come from for ODAB?
Apparently, you have a poor understanding of the physics, and even the chemistry, of a volumetric explosion.
Firstly, the only energy sources are carbon and hydrogen. In a traditional explosive, a significant part is made up of oxygen-containing NO or something. The filling of ODAB consists almost entirely of hydrocarbons. So, the TNT equivalent of such ammunition is significantly greater.
Secondly, not all explosives detonate. A significant part of it is sprayed by a detonation wave and does not participate in the explosion, unlike bulk ammunition.
Thirdly, the explosion zone itself is significantly larger. Therefore, with ODAB it is not entirely clear from which point to measure this very “cube root”.
Fourthly, a shelter that saves you from a blast wave will not save you from igniting the ODAB filling. Here you need complete tightness of the shelter.
Of course, ODAB is not a powerful loaf and the effects of such ammunition, especially in the open air, are highly dependent on weather conditions, but the lethality of ODAB is significantly higher than that of a traditional bomb.
Let’s not forget barotrauma and suffocation.

[fiv]

For ODAB, the “square root” should most likely be measured from the boundaries of an imaginary reduced hemisphere (or sphere??) with a volume corresponding to the volume of the region with the reactive concentration of fuel and oxidizer

[bk316]

For ODAB, the “square root” should most likely be measured from the boundaries of an imaginary reduced hemisphere (or sphere??) with a volume corresponding to the volume of the region with the reactive concentration of fuel and oxidizer

Well, more or less, yes.
But this changes almost nothing.
Let's take the mass of explosives in ODAB 500 300 kg
Let it form a cloud with an air density and a concentration of 5% (as you understand, less air density will not work, and 5% is a characteristic concentration for the detonation of hydrocarbons)
In total we get the volume (300/1,2)*20 = 5000 cubic meters
This is a ball with a diameter of only 17 meters.
And for ODAB 9000 it’s only 51 meters.

[bk316]

And, I’m embarrassed to ask, where does the firewood come from for ODAB?

Oh another ODAB witness.
Is it really hard to Google?
Well, here we go.
http://www.airwar.ru/weapon/ab/odab-500pm.html

ODAB-500PM has already been demonstrated so many times at various exhibitions from Max to Abu Dhabi with all the parameters, naturally, that it was time to learn and not rewrite mantras about barotrauma.

[hammer it]

Quote: Grossvater

You have a poor understanding of the physics, and indeed the chemistry, of a volumetric explosion.

A few boring numbers about specific heat and detonation speed:
TNT 15 MJ/kg during combustion and 4,2 MJ/kg during explosion. 6 m/s
Dis. fuel 43 MJ/kg, 2 m/s
Methane 75 MJ/kg, 1 m/s
Hydrogen 1 MJ/kg in air, 344 m/s air mixture.

Hydrogen is 340 times more powerful than TNT!
The most powerful chemical explosive is Octanitrocubane = Octanitrocubane (ONC) TNT equivalent 2,38, detonation speed 10 m/s.

Next we look:
The direct action of the shock wave causes lesions of varying severity: Mild lesions - 20-40 kPa (concussions, mild bruises). Moderate severity - 40-60 kPa (loss of consciousness, hearing damage, dislocation of limbs, bleeding from the nose and ears, concussion). Severe damage - more than 60 kPa (severe contusions, broken limbs, damage to internal organs). Extremely severe lesions - more than 100 kPa (fatal).

The radii of pressure zones can be calculated using the following formula: R = C * X⁰´³³³,
R is the radius in kilometers, X is the charge in kilotons, C is a constant depending on the pressure level:
C = 2.2, for 1 psi pressure
C = 1.0, for 3 psi pressure
C = 0.71, for 5 psi pressure
C = 0.45, for 10 psi pressure
C = 0.28, for 20 psi pressure

[bk316]

Thank you. Interesting, but pointless for conventional ammunition.
Firstly, because each ammunition has a TTX which is obtained not by approximate calculations, but at the test site by direct measurements (this, by the way, applies not only to ammunition, but also to protective equipment). It's much more accurate.
Secondly, to people like Alexei, whether you prove it or not, it’s all the same. They are millet believe and faith does not require proof and is not refuted by argument. But it’s better to believe in the pasta god Kuzya than to believe in such a practical thing as ODAB.

[hammer it]

Quote: bk316

Thank you. Interesting, but pointless for conventional ammunition.

Please. All these numbers are quite suitable for any landmines. Since the TNT equivalent is used.
The situation with ODAB is somewhat different.

Quote: bk316

Firstly, because each ammunition has a TTX which is obtained not by approximate calculations, but at the test site by direct measurements (this, by the way, applies not only to ammunition, but also to protective equipment). It's much more accurate.

These data were also obtained experimentally...

Quote: bk316

But it’s better to believe in the pasta god Kuzya than to believe in such a practical thing as ODAB.

In this world everything is relative. And if you recalculate the power of ammunition in TNT, then ODAB in terms of high explosiveness will indeed be much more powerful than conventional FAB.

Quote: bk316

Let it form a cloud with an air density and a concentration of 5% (as you know, it won’t work out less than the air density

Detonating gas is capable of burning in a wide range of hydrogen concentrations in the air, from 4-9 percent by volume in lean mixtures and up to 75% in rich mixtures. It is capable of detonating within approximately the same limits.

300 kg of hydrogen is 3 m³ (360% of volume). Let's add 5 m³ of air (63% of the volume). We get 840 m³ of detonating gas. Which is equal to a hemisphere with a diameter of 95 meters.
This is the radius of the explosion, from which it is necessary to calculate the range of propagation of a shock wave with a pressure of only 0,6 ATM. (60 kPa)...

In reality, everything is much more modest, of course. And God Kuzya has nothing to do with it.

[hammer it]

Quote: bk316

at the test site by direct measurements (by the way, this applies not only to ammunition, but also to protective equipment). It's much more accurate.
Secondly, to people like Alexei, whether you prove it or not, it’s all the same. They simply believe, and faith does not require evidence and is not refuted by argument. But it’s better to believe in the pasta god Kuzya,

Let's send it back to YouTube. There, his namesake demonstrates the effects of a wide variety of ammunition, including thermal bars. Epic video with RPG-7, on the channel "Large Caliber Trouble".

[vh48905]

How is the exposure time taken into account? Let's say Okfol 3.5 gives a detonation speed of the order of 9000 m/s and, accordingly, high pressure in the shock wave front, and Temobara has several times lower detonation speed and, accordingly, the pressure in the shock wave front, but due to the negative oxygen balance it burns out in the air much longer and affects person or equipment longer. How to evaluate the damage radius and effectiveness of ammunition of equal mass?

[hammer it]

Let's try from the beginning...
The volume of a solid explosive explosion is equal to the volume of the ammunition itself. And outside this volume, the wave speed decreases in cubic progression.
But detonation during a volumetric explosion occurs in the entire volume filled with explosives.
Despite the (approximately) three times lower detonation speed of the mixture, the volume of the explosion itself is comparable to the damage radius of a solid explosive of similar mass. The reaction itself of the supersonic thermodynamic transformation of the volumetric mixture is slower, which makes it possible to burn not only hydrogen, but also carbon, as well as metallic inclusions (boron, cerium, aluminum, lithium, sodium). Such a reaction is possible during the explosion of supercritical masses of solid explosives. Like saltpeter in Lebanon.
The energy intensity of the metal components of the mixture is very high. Especially boron, lithium is dangerous when in contact with oxygen even under normal conditions...

Well, the mass of the mixture in modern ODAB is 195 kg, despite the fact that in the first there was 130 piperylene... In terms of thermal power, ≈ 2 tons of TNT. Yes, with the air required for the explosion, the mixture will weigh about 2 tons...

Quote: vh48905

How to evaluate the damage radius and effectiveness of ammunition of equal mass?

Very approximately, empirically. Since the effectiveness of the mixture depends on temperature, wind speed, the presence of precipitation, humidity, the shape of the cloud and its flow into shelters. A small amount of moisture in the air is rather useful, a large amount is harmful... If you stick ODAB, like FAB, into the ground, you get zilch, deflagration - subsonic combustion.

[Sergey Valov]

“being from the epicenter” - dear author, since you have begun to write about shell explosions, then take an interest in what “the epicenter of the explosion” is.

[hammer it]

Quote: Sergey Valov

"being away from the epicenter"

Listen carefully to his calculations.
He considers the detonation of an explosive of a given mass, in the air, strictly above the patient’s head.
In this case, it takes exclusively the direct impact of a shock wave with a pressure of 100 kPa (1 ATM) as a 100% result. As a physicist he is right.
But the military considers it a complete defeat - 82%, for which a shock wave pressure of 60 kPa (0,6 ATM) is quite sufficient.

And yes, according to the technical characteristics, the radius of complete destruction of the RGD-5 = 4 meters! And not 0,9 meters is just minced meat...
What is happening in real life can be seen on the CCTV cameras of the village council meeting. In western Ukraine, a ZSU veteran detonated 4 RGD-5 grenades. The bodies of those who were closer to the explosions protected those who were behind them.

[mc1aren]

YouTube branch...
Soon they will just post links to Zen here...
sad...

[the same doctor]

The author’s figures are questionable, since they are very small, but let’s take them as a guide.
.
Moral and conclusion:
For missiles and UAV projectiles, shellless warheads with a volumetric detonating filling should be used. Then the dimensions of an 82 mm mine will fit the equivalent of 20 kg of explosives and the guaranteed lethal effect of the blast wave will be about 10 meters, which exceeds that of even a 6-inch projectile.
It is important that the absence of fragments will allow one to advance behind the barrage not at 300 meters, as usual, but at a distance of 50 meters. It will also be possible to use such ammunition directly near your fighters.
.
Conventional mines and shells have a niche for destroying shelters and tanks, as well as shooting at invisible targets. Well, with proper control, the reaction time to a detected target for barrel artillery is minimal.
.
While we do not have an abundance of guided ODB carriers (and even when there are heaps of them), we should increase the production of conventional projectiles. An ordinary projectile will not move either the electronic warfare or the shot charge from its trajectory. But it’s very easy to counteract UAVs and guided missiles, if, of course, Nabiulina gives money for development.