Thread: [Merged] Cold Fusion Claims
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Old 21st May 2013, 05:25 PM   #3122
ben m
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Originally Posted by ben m View Post
Also, you have a cylinder whose external surface was at 700 degrees and cooling radiatively. Try to get that much heat to flow out of a nickel powder. It won't, the powder will melt first. So much for "special nanocrystalline nickel" or whatever it was.
Y'know, even if you think there's nothing fraudulent in the rest of the setup, this might be the kicker. They're claiming a miracle of thermodynamics here:

a) A SiN tube, cooled by free convection, which reached 700C and 2000kW.
b) The heat source was inside the SiN, conducting through it, so clearly the interior was somewhat hotter.
c) There was apparently an air gap between the SiN cylinder and some sort of sapphire cylinder. The sapphire cylinder must have been even hotter to push 2000W across this air gap.
d) There's another thermal resistance (smaller, but not negligible) required to push heat across the sapphire ...
e) Inside another air gap is a steel surface, hotter still to push heat across the air gap to the already-hot sapphire ...
f) Inside the steel is supposedly 300mg (i.e a few cubic millimeters) of loose powdered nickel (!) which has to be SO HOT that it conducts or radiates 2000W to its steel shell.

That's quite a heat transfer problem---cooling a fuel material that outputs 6MW/kg? That's 100-1000 times the power density (10^3--10^4) of the fuel pellets in a typical nuclear reactor. I don't know about your local reactor engineers, but my local reactor engineers recommend using a billion dollars' worth of really expensive coolant pumps, high-thermal-conductivity coatings, etc., to prevent their fuel from melting down.

Rossi claims to have taken a spoonful of fuel 1000 times more intense, and stuck it in a tube, wrapped it in multiple ceramic blankets, and it sorta just worked. Huh.

Note that there's no heat-transfer difficulty if the thing was heated by the resistors.


a) A SiN tube, cooled by free convection, which reached 700C and 2000kW.
b) The heat source was inside the SiN, conducting through it, so clearly the interior was somewhat hotter.
c) The sapphire tube was heated by resistors to a somewhat hotter temperature.
d) The useless thing inside (steel tube, nickel powder if any, etc.) was in equilibrium with the resistor-heated tube around it.
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