Barry Kort on Dr bob blog reported challenging critiques of McKubre

maybe some already have the debunking, the correction... i imagien it is

About a year after CBS 60 Minutes aired their episode on Cold Fusion, I
followed up with Rob Duncan to explore Richard Garwin’s thesis that McKubre
was measuring the input electric power incorrectly.

It turns out that McKubre was reckoning only the DC power going into his
cells, and assuming (for arcane technical reasons) there could not be any
AC power going in, and therefore he didn’t need to measure or include any
AC power term in his energy budget model.

Together with several other people, I helped work out a model for the
omitted AC power term in McKubre’s experimental design. Our model showed
that there was measurable and significant AC power, arising from the
fluctuations in ohmic resistance as bubbles formed and sloughed off the
surface of the palladium electrodes. Our model jibed with both the
qualitative and quantitative evidence from McKubre’s reports:

1) McKubre (and others) noted that the excess heat only appeared after the
palladium lattice was fully loaded. And that’s precisely when the Faradaic
current no longer charges up the lattice, but begins producing gas bubbles
on the surfaces of the electrodes.

2) The excess heat in McKubre’s cells was only apparent, significant, and
sizable when the Faradaic drive current was elevated to dramatically high
levels, thereby increasing the rate at which bubbles were forming and
sloughing off the electrodes.

3) The effect was enhanced if the surface of the electrodes was rough
rather than polished smooth, so that larger bubbles could form and cling to
the rough surface before sloughing off, thereby alternately occluding and
exposing somewhat larger fractions of surface area for each bubble.

The time-varying resistance arising from the bubbles forming and sloughing
off the surface of the electrodes — after the cell was fully loaded,
enhanced by elevated Faradaic drive currents and further enhanced by a
rough electrode surface — produced measurable and significant AC noise
power into the energy budget model that went as the square of the magnitude
of the fluctuations in the cell resistance.

To a first approximation, a 17% fluctuation in resistance would nominally
produce a 3% increase in power, over and above the baseline DC power term.
Garwin and Lewis had found that McKubre’s cells were producing about 3%
more heat than could be accounted for with his energy measurements, where
McKubre was reckoning only the DC power going into his cells, and
(incorrectly) assuming there was no AC power that needed to be measured or
included in his energy budget model.

I suggest slapping an audio VU meter across McKubre’s cell to measure the
AC burst noise from the fluctuating resistance. Alternatively use one of
McKubre’s constant current power supplies to drive an old style desk
telephone with a carbon button microphone. I predict the handset will still
function: if you blow into the mouthpiece, you’ll hear it in the earpiece,
thereby proving the reality of an AC audio signal riding on top of the DC

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