I Can you use these equations to calculate explosion overpressure?

AI Thread Summary
Dr. Jorge S. Diaz's video explains modeling blast wave movement, prompting a discussion on whether the same equations can calculate blast wave overpressure based on explosive energy and distance. The original poster expresses difficulty in understanding the video and requests a transcription of the relevant equations for easier access. A suggestion is made to consult existing literature, specifically a 1967 report from Johns Hopkins Applied Physics Lab, which contains useful equations and figures for understanding air blast effects. The conversation reflects a preference for a theoretical solution over empirical equations, highlighting the challenges faced by those with limited mathematical background. Overall, the discussion emphasizes the importance of established research in calculating explosion overpressure.
Ax_xiom
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An idiot that shouldn't be doing graduate level maths attempts to do it to calculate a blast wave
So in this video Dr Jorge S. Diaz walks through a way to model the movement of a blast wave (with an explanation that I don't fully follow because I'm an idiot) and I'm wondering if it's possible to use the same equations to calculate the overpressure of a blast wave from a given explosive energy and distance (and vice versa)

Just as an heads up I've only done a bit of differential equations, I can interpete and solve basic ODEs and barely interprete PDEs but can't really solve them.
 
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Can you transcribe the problem and equations here, so every PF user doesn't have to go scan an hour long Youtube video to get up-to-speed?
 
Sorry
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So he uses these equations to get a formula that describes the movement of a blast wave in respects to time. I'm wondering if it's possible to do the same with overpressure in respects to distance
 
Ax_xiom said:
I'm wondering if it's possible to use the same equations to calculate the overpressure of a blast wave from a given explosive energy and distance (and vice versa)
Rather than trying to reinvent the wheel by performing calculations, you can easily answer this question by consulting the literature. For example, take a look at eq.(2) and fig. 2 in this 1967 report from Johns Hopkins Applied Physics Lab: Scaling the effects of air blast...
 
Last edited:
renormalize said:
Rather than trying to reinvent the wheel by performing calculations, you can easily answer this question by consulting the literature. For example, take a look at eq.(2) and fig. 2 in this 1967 report from Johns Hopkins Applied Physics Lab: Scaling the effects of air blast...
This seems like interesting, I would have prefered to have a proper solution that wasn't an empirical equation but beggars can't be choosers (I don't know how to do the maths to do it myself)
 
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