Re: [TCML] High Power Static Gaps

[Sfxneon@xxxxxxx]

Questions and ramblings to the group:
 
Besides the advantage that a rotary has in setting the break rate and  phase, 
what else does a rotary do to make it more suitable for high power work?  If 
the main advantage is the cooling/deionazation provided by rapidly moving the  
electrodes through the air, then it seems to make sense that moving the air 
over  the electrodes is much simpler and safer. The idea of a triggered static 
gap  intrigues me even more because the BPS rate can be changed, with just the 
turn  of a knob.
 
So far, I have only seen and used metals like copper and brass as  the 
electrodes in sucker or vortex gaps. Has anyone incorporated tungsten  rod into the 
design, maybe mounting a rod axially inside the hollow electrodes,  letting it 
protrude slightly out of the ends? It looks like that should  make a better 
quenching gap, than one made of softer metals. Also, the mass  and shape of the 
electrodes versus heat dissipation would need to optimized. I'm  not sure if 
bigger is better here, since surface area/mass ratio plays a big  part in 
removing heat. Would it be easier to keep a small or a large electrode  cool? 
 
Keeping the KISS principle in mind, how far can a single static gap be  
pushed without exotic cooling methods, using only the motor/turbine with  some 
applied aerodynamics and thermodynamics? There are literally millions of  vacuum 
cleaner and shop-vac motor/turbines out there already for cheap or  free, and 
these seem to be a good choice for both pressure and vacuum.  The noise can be 
almost silenced by putting it in a box with some internal  baffles and lining 
it with thick felt, fiberglass or other sound absorbing  material. I used to 
use these same vacuum motors to build vacuum pumps for  player pianos, and once 
the piano started playing, the motor could no  longer be heard.
 
Has anyone tried a regenerative sucker/vortex gap where the suction side of  
the turbine goes to one electrode, and the pressure side to the other? The  
electrodes themselves might be fashioned to act like a venturi, drawing in  
additional atmospheric air at the spark gap, and then bleeding it off on the  
pressure side of the turbine with an adjustable port.  That might increase airflow 
and pressure, if cooling didn't become a  problem. 
 
Anyway, just late night thoughts and ramblings, and all comments  appreciated!
 
Tony Greer
*************
In a message dated 9/8/2008 4:43:35 P.M. Central Daylight Time,  
futuret@xxxxxxx writes:

And this brings up the issue of whether a slightly slow quench  hurts
spark length.  It's possible that the spark length is determined  mostly
by the amount of  energy transfered during the *first* transfer  of a 
bang.
Subsequent energy transfers may add practically nothing to  the
spark length.  Thus the total gap losses may be a rather  insignificant
factor regarding output spark length.  In other words it  may be
the gap losses during the first transfer which is the  important
thing.  If so, then a single (which should have lower  gap
losses during the first transfer) should give better results.
This  would be true even if the *overall* gap losses (for
example if the quenching  suffered due to a single gap, etc) were
higher.  Evidence that it's the  first transfer which is important is
given by the fact that tighter coupling  usually give longer sparks,
even though the quench may occur at a later  notch.  Tight
coupling causes the first transfer to finish sooner.   The use of
multiple gaps seems to greatly reduce the energy of the  first
transfer.  However the gap width of a single spark gap  might
not make much difference to the output spark length.   I'm
basing this on my comparisons of a 120 bps sync rotary and a
120 bps  triggered single gap.  Both gave the same spark length
output.  Yet  the single spark gap was very wide at 5/8" or so.
However the rotary actually  had two gaps.  Since two gaps
have more losses than a single gap, this  might have caused
the results to balance out.  It could be also that my  coil
designs (high inductance primaries) tend to minimize
the effects of  gap losses anyway.  So the bottom line is
that more experiments would be  useful.

Cheers,
John
 



**************Psssst...Have you heard the news? There's a new fashion blog, 
plus the latest fall trends and hair styles at StyleList.com.      
(http://www.stylelist.com/trends?ncid=aolsty00050000000014)
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla