Temperature related to yield or type of explosion? Nuclear vs conventional.

[Researcher X]

Are the temperatures produced from a nuclear reaction special in anyway? If a 20 kiloton nuke is producing hundreds of thousands of degrees at it's center, would the same ballpark be true of 20,000 tons of TNT, which is roughly equal in yield?

 

[mgb_phys]

No - it's a question of concentrating the energy.
20,000 t of TNT fills a rather inconveniently large warehouse - putting all that energy into a few cm^3 of core is tricky.

 

[Researcher X]

So, temperature is independent of yield of energy?

I'd also like to know if you could point me somewhere I can find estimates of yield versus crater size (possibly a calculator or program) for ground contact explosions.

 

[berkeman]

So, temperature is independent of yield of energy?

No. As mgb was saying, you get higher temperatures in the nuke case because the volume of the energy source is so much smaller initially. The temperature for both nuke and TNT ratios with yield.

I'd also like to know if you could point me somewhere I can find estimates of yield versus crater size (possibly a calculator or program) for ground contact explosions.

Seems a pretty easy thing to find with Google. No luck?

 

[Researcher X]

No luck, actually. There's plenty to do with fireball/blast radius. I seem to remember one which was a program which showed the height of a building in the crater, but I think that might have been an asteroid impact one.

 

[berkeman]

No luck, actually. There's plenty to do with fireball/blast radius. I seem to remember one which was a program which showed the height of a building in the crater, but I think that might have been an asteroid impact one.

I just googled your words -- yield versus crater size, and got lots of hits. The first one is this thread here at the PF (gotta love those Google spiders), but the rest look promising. What about the 2nd hit on the list -- does it help?

http://www.google.com/search?source...GGLL_enUS301US302&q=yield+versus+crater+size+

 

[Researcher X]

Sort of, but I'm not good at maths, so I'll have to take some time working out what the formula mean. I'm actually trying to estimate how large a yield you'd need to create a 1000 meter deep transient crater. If Tsar Bomba had been a surface blast, could it have done this? I'm wondering how much power you'd need to eradicate a mountain, which is why I use "1000 meters".

I know that the Sedan Underground Test (104 kilotons) created a 100 meter deep permanent crater (the very largest man made crater), so I would guess we are talking many many Megatons here.