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wgmeisheid's avatar

Strange that I never saw this before but his diagram on page 4 of the pressure then suction duality I had never seen before. Knew about the blast/pressure issue but never noticed the suction aspect. Very important to know. The blast putting out 120mph winds at 10 miles is a big deal. Wish he had given a timing statement, like the suction arrives Xseconds/minutes after the blast/pressure portion.

I did some quick Internet searching and found a document that details this effect. https://atomicarchive.com/resources/documents/effects/glasstone-dolan/chapter2.html

The blast wave is supersonic and moves about 4 sec/mile. So, if you see a blast 10 miles away you have a little over 40 seconds to find shelter from the blast. There is an additional problem of the overpressure/Mach effect which is approximately 2x blast pressure.

Contrary to his diagram they state the suction phase is relatively weak compared to the blast pressure. "During this negative (or suction) phase, the pressure in the shock wave is less than the ambient atmospheric pressure. However, as seen in § 3.05, the underpressure is never very large."

Thought I would pass that on.

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EK MtnTime's avatar

Thanks 😊

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Simon Tanner's avatar

Another Paladin Press gem! Man, Duncan Long, another pioneer. So many of these guys were way ahead of the curve. They had it figured out 30-40 years ago. I really appreciate you making sure there work doesn’t fade away.

I like to imagine what that generation of authors could have done with the internet and something Substack. Thanks for bringing them to it in a way.

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SKY DOG's avatar

Hey Texas,

Duncan got ill and passed away some time ago. I am sure he wouldn't mind his older works being passed around.

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Texas Arcane's avatar

His books were awesome! Going to hunt up older titles right now. Sorry to hear he passed away.

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