Re: water spark gaps

["Tesla list" <tesla-at-xxxxxxxxxx>]

Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net> 

> The picture shows a rather dramatic firing at only 150 joules!  Our gaps
> may "dissipate" only around 5 joules per bang but at 120 times per
> second...  Also the gap may produce explosive or at least flammable gasses
> even on a good day...  There may be a chance that high energy discharges in
> water will break the water into H2 and O2 gas and then ignite it to really
> give a good "bang" either right then or after the gas has built up for
> awhile.  Obviously, such effects are undesirable in our application.  If we
> cause a small explosion of the water dielectric, there is some danger and

however, the maximum energy you could get out of recombining the
dissociated water is no more than you put into it to dissociate it.   If
most of that 5 joules per bang is going into the coil and into heat, very
few millijoules are dissociating the water, and anyway, when that H2O2
mixture is ignited, it just makes the same number of millijoules (as
heat..).. The net result is the same as if the dissociation energy were
directly turned into heat.  I suspect that the flame speed (if any) is low
enough that the energy rate (power) of the recombination is much lower than
the energy rate of the thermal heating due to the arc.

Now.. if you put the gap in a big container, ran HV into and didn't let it
breakdown, or did, but most of the time it wasn't breaking down, but was
dissociating the water, and accumulating H2/O2 mix in the container, you
could get some excitement... nothing that venting the container wouldn't
fix, though..
You'd also see bubbles on the spark gap electrodes...


> 
> I am glad I asked first before messing with all this.  I would not have
> seriously considered explosions before!
> 
> On another note, this takes pure de-ionized water and all that to get a
> high electrical resistance which is important for a water gap (although
> adding axillary gap may be an alternative).  I "assume" one of those fancy
> bottled waters, like Aqua-Pure, would be appropriate?

Actually, the cheapest of cheap DI water, as suitable for steam irons...,
should work... 

> 
> Cheers,
>