At 12:30 PM 8/17/2011, Alan J Fletcher wrote:
http://lenr.qumbu.com/rossi_ecat_steam_v410A.php (Working Draft)
Comments and corrections appreciated -- either through vortex or directly
Abstract
The issue of Steam Quality greatly impacts the calculations on the
actual excess energy.
This issue is extensively analyzed by Steven B. Krivit in
<http://newenergytimes.com/v2/news/2011/37/NET370.shtml>New Energy
Times Issue 37
In particular,
<http://newenergytimes.com/v2/news/2011/37/3714appendixelectriconly.shtml>Appendix
9: NASA Electrical-Power-Only Steam Analysis reviews the performance
of the eCat in relation to an Temperature-Entropy diagram, and
states that the Steam quality could be any value between 0 and 1, so
that the total output power could be anywhere between 770 watts (NO
excess energy), to slightly above Rossi's claimed value of 4900 Watts
"0 and 1" is a rough summary. In fact, 1 (i.e, 100% vapor) is
extremely unlikely. Most boilers operate at around 95%, normal
boilers won't go below about 90% worst-case. However, it's quite
possible to design a device that will essentially atomize the liquid,
making as low as 5% or so possible, and 0% is also possible (but it
would be on a knife-edge; like 100%, the "steam" -- hot water at
boiling temperature -- would not be temperature stabilized.
This article shows that NASA's analysis omits significant facts
about the behaviour of steam.
First, we review some basic facts about steam, particularly the
concept of steam quality, and the use of a temperature-enthalpy
diagram. We then consider the detailed behavior of boiling water in
a "Kettle" boiler and a "Tube" boiler.
In a tube boiler, such as the eCat, the distribution of liquid water
and water vapour depends directly on the Steam quality. As steam
quality increases from 0 to 1 the flow changes in stages from pure
liquid, bubbly liquid, plugs of steam/slugs of water to an annular
arrangement of liquid water and vapour containing droplets. At a
specific steam quality a "Dryout" occurs : there is no more liquid
water in the output. Any remaining water will then be carried as
droplets in the water vapour. This "Dryout Point" is estimated by
the author to be between 75% dry and 80% dry.
Seems right to me. That's a misnomer. The steam is not dry at that
point. Rather, liquid water is being carried by the flow as suspended droplets.
Because the measure of wetness is by mass, traditionally, it's
possible for quite wet steam, under some conditions, to be carrying a
lot of water, depending on velocity, turbulence, etc. I've speculated
that one could be making, with the Rossi E-cat design, steam as low
as 5% quality.
One way to describe what the author is calling "dryout" is "fog." How
heavy a fog could be made at the boiling point? In these devices, if
there is high vaporization, the steam velocity is quite high, and
could keep relatively large droplets or relatively dense fog
suspended. Is there experimental data on this? Where?
If the eCat is operating with a steam quality BELOW the dryout point
then liquid water will eventually fill the chimney and flow out of
the outlet hose. If the eCat has steam quality ABOVE the dryout
point, then the chimney will empty, and there will be no liquid
water in the outlet hose.
That's, again, quite misleading and incorrect. The steam cools in the
outlet hose, and liquid water being carried by the steam is still
liquid water. It's just suspended, that's all. And as the steam cools
in the hose, steam will (it must!) condense, and some of this will
amalgamate as water.
It has been asserted that the chimney was dry, specifically by
Galantini, using "eyeballing." That could be quite misleading. There
is pressure in the chimney, raising the boiling point by perhaps a
degree C. If there is a thin film of water on a probe, and the probe
has been allowed to adjust to the internal temperature, both the
probe and adhering water will be above the ambient boiling point,
i.e, when the probe is withdrawn, the water would immediately
vaporize when the pressure is relieved. There would be much more
definitive ways of ruling out liquid water overflow, but they were not used.
The bottom line: there is absolutely inadequate data to come to firm
conclusions on the Rossi demonstration results. Because there are
some indications that some level of fraud or deception (or allowance
of mistaken assumptions) has taken place, such as adjustment of input
power without discloser of the changes, the demonstrations must be
taken as *competely unreliable.* That's unfortunate, but that's the way it is.
The author believes that the experiments show that the chimney is
NOT full of water, and that significant amounts of liquid water are
NOT in the outlet stream.
Authors may believe what they like, but we have extremely little
experimental data to rely upon, essentialy anecdotal reports, where
unknown caution was exercised.
The MINIMUM steam quality is thus ABOVE the dryout point, which
means that the steam quality is above 75% Dry, and the total power
is over 4300 watts, much larger than the electrical input of 770 Watts.
The data to back this up isn't even cited. Not great.
Note 1 : this is a working draft. Some of these calculations have
been "eyeballed", and will be replaced with more accurate numbers.
Check back frequently for updates.
Note 2 : when researching "dryout" be sure to distinguish between
"local dryout" (Leidenfrost), and "total dryout", when there is no more water.
If this is a standard term, great. If not, Bad Idea.
