Cratering question (calc-help)

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Shadow WarChief
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Cratering question (calc-help)

Post by Shadow WarChief »

For these calcs I'm trying to do, I need to know how much energy is required to make a crater 29.27 meters in diameter.

I have no idea where to begin with this so could someone help me?


Also, is there an equation where you could just plug in crater size/ energy and get energy/crater size?
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Durandal
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Post by Durandal »

What material? What method? Are you blowing the material away? Are you vaporizing it? Transitioning it out of the continuum? How far away is the ejecta going to go?

You need to give a lot more information.
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Darth Wong
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Post by Darth Wong »

If we assume you are merely excavating dirt (as opposed to cratering a giant piece of nickel-iron, for example), we can start from the fact that an M180 cratering demolition kit uses a shaped charge to bury a 40 pound charge to optimal depth. It creates a 12-22 foot diameter crater (let's say 17 foot average).

Cratering is a volumetric effect, so we can roughly estimate that it should follow the third power scaling law. Therefore, it would take a 3.5 ton charge to produce a 30 metre diameter crater. Of course, there are numerous assumptions therein; it would be good to know the exact scenario.
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Sea Skimmer
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Post by Sea Skimmer »

The shaped charges job is to blast a deep narrow hole and a rocket shoves the main charge down into it. That’s why the size can vary by huge margins even in the same material. The depth of the burial is key.
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Shadow WarChief
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Post by Shadow WarChief »

Durandal wrote: You need to give a lot more information.
Like I said earlier..."I have no idea where to begin with this"
I'll try to answer your questions as best I can.
Durandal wrote:What material?
Concrete


Durandal wrote:Are you blowing the material away?

yes

Durandal wrote: Are you vaporizing it?
From what I see onscreen, there is no vaporization or melting. Though I don't think you could rule it out. Considering we don't see what's in the crater after the blast.

Durandal wrote:Transitioning it out of the continuum?
:?
Durandal wrote: How far away is the ejecta going to go?
the ejecta comes to rest 130 feet from the center of the crater. It's average velocity was 60 feet/second
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