I have attached a little drawing that might help save the cell case from total destruction. It would allow the expansion to simply lift the top cover just like a large safety valve.
As an aside, I remember reading about the specification for the early Brayton cycle engines. These engines mixed air and Town gas and then compressed it into a storage chamber that was also part of the engine's construction. It was stated that the casing must be made of the finest Ordnance Bronze to withstand a blow back, which, from what I can gather, they suffered quite often !! They too had a large diameter cap held down by springs as a safety device.
If it is of any consolation we are now into double figure bubbler destruction !!
Cheers Grum.
Graham (& others),
Excuse me saying so but destroying flash-back arrestors one after the other, is the WRONG approach to 'solve' flash-back problems!
It should be obvious (and logical!) that the very first thing which MUST be done is to ELIMINATE the source or reason for the 'flash-backs' in the first place!
Period.
It is perfectly possible to make backfire-free set-ups, where flash-back arrestors are only needed as safety devices, in case of malfunctioning parts or equipment.
Further, it is also perfectly possible to make electrolysers which can withstand the full force of any flashback!
Graham, I would like to point out that the spring-loaded top would NOT save the electrolyser from blowing to pieces!
I can give you two examples of WHY that is so:
One is an experiment done by Dr William Rhodes, the inventor of the multi-cell electrolysis,
the other is my own, repeated experiments, proving the same point!
Here is a quote from a document written by Dr William Rhodes:
“
It is noted that any sharp metallic whisker in the storage atmosphere could cause an explosion, similar to the dangers of storing high percentage hydrogen peroxide,
where the entire contents can burst into high pressure steam with disastrous results,
just because somewhere in the interior someone forgot to round off a sharp edge.
On the other hand, these mixed gases were ignited repeatedly in a 4 liter container of 16 gage iron with flat ends and spark plug.
The only evidence of ignition was a sharp click, with no damage to the vessel.A recent report revealed one experimenter was wounded with shrapnel from such explosion.
The only way this might happen is from accumulation in an unusually thin container, or one made from an easily fractured plastic.
However, a duplication of the original multicell unit was constructed of 3/4" Plexiglas with an interior volume of 8 liters.
Half of this was filled with electrolyte leaving 4 liters for foam and gas accumulation, (Identical to the volume of the iron container).
The multicell had a 2.5" diameter rupturable diaphragm of food grade Saran wrap.
The unit was set on a stand in the open and ignited.
The resultant pop splintered the case into many pieces which were all deposited within a radius of 5 feet around the stand.
The diaphragm remained intact.Such indicated the sonic wave front was responsible instead of pressure which would have ruptured the diaphragm.
These tests allowed us to design electrolyzer tanks of materials and thicknesses that could contain flashbacks.
Viewing the permanent Plexiglas multicell in operation, electrolyte foam rises upward, but at maximum elevation allows sufficient gas space above.
Therefore no purpose is served with designs containing more gas than necessary for conduction out of the reservoir.
Extrapolation of chart curves indicate a possible diesel type explosion as pressure approaches 400 psi.
However, this is not conclusive.
Generation of such single ducted gases appears to be an event not found in nature, unless lightening produces them.
(For more details, see attached article.)
The second example is my own experience.
My first 120 cell electrolyser –
without a top - was used for a large number of explosion tests!
It was simply placed in a large, open plastic box on the floor so any electrolyte spill was contained.
Every time someone who was interested in water fuel visited me, I was showing them the power of 'Brown's Gas'!
The “test” was simple.
Applied power to the electrolyser for just a few seconds, bubbles formed on the entire top surface,
then turned the power off.
Lit a match and threw it on the top of the electrolyser!
DEAFENING explosions with just a few bubbles, NO pressure involved!
You probably can't imagine the effect of this 'demo' on most people!
The point of the story is that after a few of those 'explosions', the 15 mm thick Acrylic casing was cracking MANY places and started leaking electrolyte (but it did not explode).
All that with an OPEN top.So yes, SHOCKWAVES, NOT pressure which does the damage!
Cheers,
Les Banki