I hope this is a good place to ask this:(adsbygoogle = window.adsbygoogle || []).push({});

I'm trying to model how an object such as a kevlar vest performs in stopping

a high velocity projectile such as a bullet.

I have only basic knowledge of energy and momentum etc. but can learn if directed.

I can calculate the Ke of the bullet (half mv squared) but don't know if thats a good

starting point or where to go from there. I have the DuPont PDF for the kevlar

but dont really know how to apply the data. Especially since different weaves and

materials may be employed.

A starting point would be helpful though.

Eventually I want the model (in excel if I can) to be able to substitute variables

such as types of materials and different impact energies etc.

I'd especially like to know how to calculate the consequences of different levels

of rigidity of the target (from free floating net to fully rigid solid vest) The idea of this

being to enable different types of impact to be modelled to the point where an approximation

of design can be suggested for different impacts.

(Yes I know ceramics etc are used also - but I'm not designing actual body armour)

I'm interested in the energies involved in deflecting the projectile - kevlar being my

first (and obvious) test material.

Any pointers or indications of existing methods full or partial would be very welcome.

I know its a bit of a tall order.

Thanks for any assistance.

jack

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# How to calculate impact/stopping power energies

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