From: Bruce_Dunn@mindlink.bc.ca (Bruce Dunn)
Subject: Electrolyte gases as an overlooked variable
Organization: MIND LINK! - British Columbia, Canada
Date: Mon, 4 Jan 1993 00:40:56 GMT

     A variety of reports have suggested that there may be something
different about anomalous heat experiments run in "open" cells and in sealed
cells with recombiners.  Terry Bollinger's recent discussion of the
possibility of sonofusion indicate that for this postulated fusion mechanism,
the types and concentrations of dissolved gases in the liquid play a very
important role in what happens in a collapsing bubble.  Some thinking on my
part has suggested that various experimental setups trying to demonstrate
anomalous heat are likely to have widely different compositions of dissolved
gases in their electrolytes.  It is possible that these differences are
related to whether or not anomalous heat is produced.

     There is far more gas in the headspace of the cells than is dissolved in
the electrolyte.  Through gas interchange through the electrolyte/headspace
surface, the concentrations of gases dissolved in the electrolyte will tend
to equilibrate with the concentrations of gases in the headspace.  The amount
of a given dissolved gas in the bulk of the electrolyte will therefore
depend, among other things,  on the partial pressure of the gas in the
headspace.  Other factors of course apply - the continued production of
oxygen and hydrogen bubbles in the electrolyte will tend to flush other gases
from the electrolyte unless counterbalanced by a similar inflow of the gas
from the headspace.   The electrolyte near electrodes will tend to be
enriched in hydrogen or oxygen, due to electrolysis.

     In going back in my mind over the types of experiments which have been
reported, I think that I can distinguish at least 5 types of anomalous heat
experiments which are distinguishable not by their electrode and electrolyte
composition, but by what the composition of the headspace gas is and how it
got that way.   I list these below, along with what I think the partial
pressures of oxygen, nitrogen and hydrogen are likely to be.



Type 1:  No recombiner, wide open cell with air accessible surface

- headspace of cell will be largely air, enriched slightly with oxygen and
hydrogen

- steady state partial pressures of gases in headspace:

O2     20 kPa
N2     80 kPa
H2     trace


Type 2:  No recombiner, outflow of gas through a narrow orifice or a bubbler

- during initial charging, electrolytic hydrogen will be absorbed by the
electrode and electrolytic oxygen will flush nitrogen from the cell
- once hydrogen starts to be liberated, the headspace will be stochiometric
hydrogen and oxygen
- in steady state conditions nitrogen will have been flushed from the cell by
the constant flow of gas and will be kept from the cell by the constant gas
flow through the orifice or by the bubbler

- steady state partial pressures of gases in headspace:

O2     33 kPa
N2     none
H2     66 kPa

Type 3:  Recombiner, outflow of gas through a bubbler

- headspace of cell initially air, but some nitrogen is flushed out by the
excess volume of oxygen produced during charging, and headspace converts to
an oxygen enriched atmosphere
- once hydrogen starts to be liberated, hydrogen will be recombined with
oxygen; a low level of hydrogen will be maintained as the recombiner cannot
drive the hydrogen level to zero
- the bubbler will keep atmospheric nitrogen from getting back into the
system

- partial pressures of gases in headspace

O2     20 to 100 kPa, likely above 50 kPa
N2     80 to 0 kPa, likely below 50 kPa
H2     trace

O2 and N2 partial pressure add to 100 kPa; the more efficient the flushing,
the higher the O2 partial pressure and the lower the N2 partial pressure




Type 4:  Recombiner, outflow of gas through a narrow orifice

- headspace of cell initially air, but nitrogen is flushed out by the excess
volume of oxygen produced during charging, and headspace converts to an
oxygen enriched atmosphere
- once hydrogen starts to be liberated, hydrogen will be recombined with
oxygen; a low level of hydrogen will be maintained as the recombiner cannot
drive the hydrogen level to zero
- once charging is finished, there will no longer be a net flow of gas
through the orifice, and nitrogen from the surrounding air can diffuse back
into the cell; eventually, the headspace will approximate air

- initial partial pressures of gases in headspace

O2     20 to 100 kPa, likely above 50 kPa
N2     80 to 0 kPa, likely below 50 kPa
H2     trace

O2 and N2 partial pressure add to 100 kPa; the more efficient the flushing,
the higher the O2 partial pressure and the lower the N2 partial pressure


- steady state partial pressure of gases in headspace (after air diffusion)

O2     20 kPa
N2     80 kPa
H2     trace



Type 5:  Recombiner, outflow of gas captured in a constant pressure syringe,
bellows or similar arrangement

- headspace of cell initially air, but nitrogen is flushed out by the excess
volume of oxygen produced during charging, and headspace converts to an
oxygen enriched atmosphere
- once hydrogen starts to be liberated, hydrogen will be recombined with
oxygen; a low level of hydrogen will be maintained as the recombiner cannot
drive the hydrogen level to zero
- with time, the nitrogen displaced into the syringe will diffuse back to
give a uniform gas composition throughout the system.  The level of nitrogen
will depend on the ratio between the volume of air initially sealed inside
the headspace/syringe combination, and the volume of oxygen generated during
charging

- initial partial pressures of gases in headspace

O2     20 to 100 kPa, likely above 50 kPa
N2     80 to 0 kPa, likely below 50 kPa
H2     trace

O2 and N2 partial pressure add to 100 kPa; the more efficient the flushing,
the higher the O2 partial pressure and the lower the N2 partial pressure

- steady state partial pressure of gases in headspace (assuming as an example
that the volume of oxygen generated during charging is equal to the gas
volume of the system when first sealed)

O2     60 kPa
N2     40 kPa
H2     trace

Summary Table
Steady State Partial Pressure of Gas after Long Term Operation

Type of Cell                             O2        N2        H2

1  No recombiner, completely open        20        80        trace
2  No recombiner, bubbler or orifice     33        none      66
3  Recombiner, bubbler                  >50       <50        trace
4  Recombiner, orifice                   20        80        trace
5  Recombiner, syringe or bellows        60        40        trace

     Immediately noticeable is the fact that the highest nitrogen
concentrations are available in Type 1 open cells, which is the type of cell
where anomalous heat has most often been reported.  The same level of
nitrogen could in principle be eventually available in a Type 4 cell, but
only after equilibration with the atmosphere.  Type 4 cells early in their
life would more resemble type 3 cells in their gas composition.

     Note that adding a bubbler to a Type 1 cell will turn it into a Type 2
cell and very quickly result in the elimination of nitrogen from the system.
If I remember correctly, adding a bubbler to a nickel cell kills the
anomalous heat.

     To speculate, the level of nitrogen in the headspace (and thus in the
electrolyte) may affect anomalous heat production if it is proceeding via
sonofusion.  This could occur because:

Possibility 1:  The nitrogen may be involved in atomic reactions (are there
any possible paths which fit the evidence ?)

Possibility 2:  The nitrogen may be involved in Terry Bollinger's "secondary
wedging" in which a shell of compressed nitrogen inside a collapsing bubble
squirts hydrogen at high speed to the center of the bubble.

     If secondary wedging is operating, one may ask why oxygen can't
participate as well as nitrogen.  Perhaps at some intermediate temperature
during bubble collapse, oxygen reacts with hydrogen rather than wedging it.
The availability of hydrogen to be accelerated therefore may be controlled by
the local hydrogen to oxygen ratio - only if there is more than a
stochiometric amount of hydrogen will there be any left over to participate
in high temperature reactions as the cavity finishes its collapse.
Sonofusion may therefore depend on getting the ratios of dissolved hydrogen,
oxygen and nitrogen just right.  Speculatively, there must be more hydrogen
than oxygen (in order to leave free hydrogen) and there must be the correct
nitrogen to hydrogen ratio to give secondary wedging.

There may be a possibility that when there are appreciable amounts of both
dissolved hydrogen and oxygen, there is amplification of the strength of
bubble collapse.  In this scenario, during the generation of the void, oxygen
and hydrogen would degas from the liquid and enter the void.  During the
subsequent collapse of the void, the high temperatures generated would
trigger the reaction of the hydrogen and oxygen.  The chemical energy
released would add to the kinetic energy of the collapsing liquid.


Where to go from here:

1) Probably a lot more thought should be given to electrolyte levels of
hydrogen, oxygen and nitrogen in anomalous heat experiments, and how they are
affected by the experimental setup used.  At the very least, some
measurements of head space gases would be useful.

2)  It might be useful to design a setup in which the cell could constantly
be flushed with a premixed gas mixture.  Perhaps a flow calorimeter could be
designed, in which the insulated cell is cooled by bubbling pre-humidified
cool gas through the electrolyte.  Gas coming out of the cell would be run
through a recombiner, and heat output measured by using a separate setup to
measure the heat content of the evolved hot gas stream.

3)  Sonofusion experiments should explore a range of gas mixtures for
equilibration with the working fluid.  If for example nitrogen (MW 28) were
thought to be involved in secondary wedging, it would be interesting to
replace it with say neon (AW 20), argon (AW 40), or krypton (AW 84).

--
Bruce Dunn    Vancouver, Canada   Bruce_Dunn@mindlink.bc.ca
Newsgroups: sci.physics.fusion