Energy Release of C4 Explosive

[DanielJob07]

Is there a mathematical solution to calculate the impulse or energy delivered to an object when a spherical C4 explosive charge of given weight (750g) is detonated at a given stand-off (547mm or 847mm) from a test object of given area (0.4m^2)?

I am able to convert from impulse to energy by using the formula E=I^2/2m
where E is energy uptake in Joules, I is the overall impulse (N.s) applied to the test object of m kg.

I have a report from an experiment conducted by a third party showing a computer generated impulse distribution of one of the explosions and a stagement saying the impulse applied to the test object from one explosion is 384 N.s however i am unawear how they arrived at this figure and how to calculate the impulse for different charge sizes and stand-offs?

Thanks.
Dan.

...I'm not sure if i have posted this in the right category?! any suggestions are welcome?

 

[Jhero]

Dear Dan,

Thank you for your question. I can assure you that there is indeed a mathematical solution to calculate the impulse or energy delivered to an object when a spherical C4 explosive charge is detonated at a given stand-off from a test object of given area. The formula you have mentioned, E=I^2/2m, is correct for calculating energy uptake in Joules. However, there are a few other factors that need to be taken into consideration in order to accurately calculate the impulse or energy delivered to the test object.

Firstly, the weight of the explosive charge and the stand-off distance are important parameters that affect the impulse or energy delivered. The weight of the explosive charge determines the amount of energy released during the explosion, while the stand-off distance determines the distance the shock wave travels before reaching the test object. Both of these factors will have a direct impact on the overall impulse applied to the test object.

Secondly, the area of the test object also plays a crucial role in determining the impulse or energy delivered. This is because the area of the test object will determine the amount of force that is exerted on it by the shock wave. In your case, the given area of 0.4m^2 will need to be taken into consideration when calculating the impulse or energy delivered to the test object.

To accurately calculate the impulse or energy delivered to the test object, you will need to use the following formula:

I = m * (v2-v1)

Where I is the impulse in N.s, m is the mass of the test object in kg, and (v2-v1) is the difference in velocity of the test object before and after the explosion. This formula takes into account the weight of the explosive charge, the stand-off distance, and the area of the test object.

In order to calculate the impulse for different charge sizes and stand-offs, you will need to use this formula for each different scenario. You can also use a computer program or simulation to model different scenarios and calculate the impulse or energy delivered to the test object.

I hope this helps answer your question. If you have any further inquiries, please feel free to reach out to me.