A lower emissivity setting gives a higher temperature, yes, but then on calculating power, the lower emissivity gives lower power. This should be a wash, except for corrections to the limited wavelength range that the camera measures. Whether this correction favors higher power or not is far from clear, especially if the emissivity is wavelength dependent. So, it is far from obvious that using emissivity of 1 is conservative. It's entirely possible that Rossi found a paint that errs in his favor.
On Mon, May 27, 2013 at 2:44 PM, Jones Beene <[email protected]> wrote: > ** ** > > The camera which calculates the temperature of HotCat is based on > converting radiance into a corresponding temperature – and that camera has > a setting for blackbody emissivity, which is usually near one at higher > temperature. **** > > ** ** > > Levi & the Swedes (sounds like the new ABBA) used the most conservative > setting – one.**** > > ** ** > > That device is solving for T not for P.**** > > ** ** > > If you entered .33 for the value of epsilon - instead of one, then the > temperature will appear to be much higher, not lower. That is precisely why > Levi & the Swedes correctly stated that they used the most conservative > setting.**** > > ** ** > > It was Motl who got it backwards and that is why the correct answer was > deleted from his blog. Vanity, vanity.**** > > ** ** > > ** ** > > ** ** > > *From:* Andrew **** > > ** ** > > Ekstrom's critique made me think about the output side more. I've been > making a mistake about emissivity. **** > > P = s*e*T^4 (s=Boltzmann's constant, e = emissivity, T=temp in deg K).**** > > At a measured temperature, if the actual emissivity is lower than the > value used to calculate output power, then the actual output power will > indeed be less than the calculated value.**** > > **** > > Bottom line is that if the emissivity is actually 3 times lower than > thought, then what was thought to be a COP=3 changes to a COP=1.**** > > **** > > It wasn't Motl that had it backwards - it was I. Oh and also the guy who > got deleted from Motl's blog (apologies but I don't remember who that was). > And I remember Jed agreeing with me, so there's at least 3 of us who had it > wrong.**** > > **** > > Andrew**** > > **** > > **** > > ----- Original Message ----- **** > > *From:* Jed Rothwell <[email protected]> **** > > *To:* [email protected] **** > > *Sent:* Monday, May 27, 2013 11:20 AM**** > > *Subject:* [Vo]:Ekstrom critique of Levi et al.**** > > ** ** > > "Comments on the report 'Indication of anomalous heat energy production in > a reactor device containing hydrogen loaded nickel powder' by Giuseppe Levi > et al." **** > > ** ** > > Peter Ekström, Department of Physics, Lund University > > http://nuclearphysics.nuclear.lu.se/lpe/files/62739576.pdf > > > This document stands as its own rebuttal. **** > > ** ** > > - ed**** > > ** ** > >
