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Plasma stuff!

Discussion in 'High Voltage' started by Dr_Doggy, May 18, 2015.

  1. Dr_Doggy

    Dr_Doggy Well-Known Member

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    so far i have assembled my vacuum pump to the chamber and added plugs for my electrodes, I am running neon sign transformer off of variac monitored by voltmeter, I have also hooked my scope to air coil to pick up EM, I wonder if this coil is even working?

    Let me start now with the second run: I have replaced the anode and cathode with better insulated HV wire I cut from flyback transformer. Even with the better insulation it is still burning and getting peeled back as we go, also i had to go out and get hd camera to capture some of the effects i am seeing in the plasma, as my other cams are just showing white blotches. The images attached are all from the second run and have been balanced to see the colors in the plasma that i am seeing.
    a)the first photo is the AC field with ambient pressure,i am guessing this just runs at 60hz.
    b)The second photo shows the system forming and the electrodes glowing brightly also glowing is where the insulation is burning(t) off. you can also see where the corona is building between.
    c)Third I took a snap shot of these red pulses that are forming randomly and only last for a split second.
    d)As we proceed you can see the red pulses start to become more spuratic and after a bit of tweaking pressure and voltage we can see those domains form shells of light and dark, I am wondering what these shells are and how they are forming, all i can think of is cause of the AC field which is run at 60hz, but as the pink pulses form you can see them as arc breakdown activity on the oscilloscope, according to the scope the signal is running at MHZ, but if i measure the distance of 1red domain + 1 black domain = about 1-2mm, and if lambda=v/f then 2mm= 300ghz, is that last assumption correct? are any of these assumptions correct?
    e) this next image the domains form and stabilize again these mysterious rings appear, again the scope goes crazy. can someone explain these rings and their frequency?

    also, besides HV, is this dangerous, do i need to worry about xrays, or any other radiation?
     

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  2. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    Arcs for very low negative ESR such as those in XRay tubes with very high current arcs of inductive switching of high current like a 10 Hz relaxation oscillator muffled acoustically should sound like your dental XRay machine.

    Corona on audio amps will be usually continuous at 2x line frequency. But if arcing badly practically will generate UHF at half wavelength and harmonics at low power.

    Alternating DC needle air ionizers give off nuisance levels of UHF at rep rate bursts, high peaks but very low average power.

    Flyback pulse currents without leaded glass on a CRT will produce XRays but not enough for good photos, but bad for eyes up close.

    Hot anode gives warm IR / red emissions. Thermal profile affects intensity.
    Cathode gives cooler blue corona... Or did I get that backwards.
     
    Last edited: May 20, 2015
  3. Dr_Doggy

    Dr_Doggy Well-Known Member

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    just to confirm , i am using neon sign transformer on 60 hz.
    And i can figure polarity stuff later as well! Also please confirm i can look in there without getting x-rays radiation!? As far as i understand from wiki x-rays will emit anytime i get arcs, or more specifically, electrons hitting metal...

    I see blue corona that glows steadily, and does nothing unusual. off both posts as soon as I turn everything on. The blue corona is always there, but red develops over top of blue as chamber "charges"

    I have lots of questions about the red stuff though, I am not sure why it does not form till later in the process ie.. about 1 min after running blue corona (and blue is still there).
    also what interests me about this are the domains it forms, I have seen in microwave pulse vids where the domains are related to the pressure , but i wonder what other
    factors contribute, as my rings seem pretty static in distance from each other, and when i adjust volts this distance does not change, but size of red does change.

    If i get what you are saying it is only turning red due to it getting hotter?
     
  4. dave

    Dave New Member

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  5. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    No worries about Xrays unless you have >72kV in the mA range. The energy is in the >>kJ discharge range depending on medium.

    Pretty charge clouds are just that.

    Its like trying to leave Earth's orbit with a rocket that doesn't have enough juice to reach the escape velocity which is twice the centripetal velocity of a Geostationary satellite.

    This is the excitation needed to break thru an atom's electron orbit get swing around or collide with a subatomic particle with enough velocity to escape orbit.
    bremsstrahlung effect.
     
    Last edited: May 21, 2015
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  6. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    I remember photographing an old ceramic head for a 14" disk drive in a super-vacuum with 50kV in our SEM in the lab and it burnt a microinch hole in the ceramic head after charge clouds accumulated like stratus clouds over the atmosphere then caused lightning like ESD. It was pretty interesting slow motion effect.

    Lightning generates X-Rays but for such a short duration, it does no harm. It is nit fom e main arc, but rather the leaders of tiny daisy-chained partial discharges (PD) over tiny molecular gaps.

    Glass blocks most soft X-Ray particles like rain blocks microwave.
    Hard X-Rays are much higher frequency can go thru glass but take much more energy to create.
    image.jpg

    The reason for this from my experience is that the rise time needs to be less than a half cycle at X-Ray frequencies, which also means the gap must be smaller than the half wavelength. But it is not the total gap which can cause X-Rays, but rather the partial discharge (PD) which occurs prior to the breakdown or arc discharge, sometimes called leaders in lightning.

    The problem with this photo evidential experiment , IMHO, was the air in this lab was too clean and lacked the small gap PD effects cascaded in lightning leaders thru dusty air which cause the X-Rays. Normal factory=Class 100k~1M, office=50k, HEPA filter 10k booth, Sealed Class 100 Clean room =1 from HEPA to 1k on floor if disturbed
    These classes are >0.5um per cu.ft.

    These are my own opinions from my experience.
     
    Last edited: May 22, 2015
  7. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    In terms of electron volts this is the excitation energy to get electrons out of their orbit from the conductor.
    Like a rocket excaping earth or the moon, the medium, shifts the energy level.
    [​IMG]
    The higher the excitation energy above threshold, the higher the energetic release of particles
     
  8. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    The gas type inserted after you pull a vacuum, affects the energy level of visible radiation, the variation of EM fields from antenna effects, modulates the intensity with standing waves. So it is all low energy from the photos, but I dont see any meaningful measurements. The scope must be well shielded and isolated from magnetic fields, using orthogonal orientation, shielded coax with ferrite sleeves or baluns or chokes, you can reduce the RFI levels conducted, but radiated is easy to make scope go crazy with a magnet or varying magnetic field. Thats how they work.
     
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  9. Dr_Doggy

    Dr_Doggy Well-Known Member

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    very informative, kudos Tony!,
    post 4 makes much sense, was going to add a multiplier circuit but i will keep to only a few stages to avoid such volts, also good read on bremsstrahlung effect. I have noticed though that it only pertains to xrays? I was also reading about ionization energy, it sounds similar, i wonder, is there a similar type emission when using metals lighter than heavy ones?
    Also i have been reading about second ionization energy , is there such thing as third and fourth? actually , dont worry about going in to detail with this question for now, i will ask more questions re this later....

    I feel much safer now sticking my nose up against the view port. But I am still focused on these pretty lights, I now realize that the motion on scope is just the noise from the arc breaking down,

    But i still wonder about these domains, the blue plasma looks like a smooth fuzzy fungus growing, but then later when the red shows as you can see it forms dark vs bright domains, shown in the photos I was able to take in previous post, I get these fields, which show up as arcs but also seem more stabilized than a spark(or few), again in this photo i use KV insulated wire, with atmosphere in my vacuum.

    I realize the domains are most likely related to the pressure , and the force of repulsion between the charges of particles, much like standing waves work in ultrasound. But usually i see spectra of oxygen and nitrogen to be blue , i don't understand nor have ever seen the red component.

    On my first run, which i would like to bring focus on, i used a high current wire/normal insulation, a few steps over 12awg, with a black insulation, I mention this cause it was the only difference in runs, aside from the fact i didn't have video equipment set up. and maybe gap size was different.

    The reason I mention this, and what has really caught my attention in all this is what happened when i was doing my first run, initially this was just to test the insulation on my nodes, but got some very strange effects, and im not sure how:
    I'm not sure either how I get the red to form (or change) whether it was a ionic buildup or impact from changing voltage/pressure. but thats all i really did. BUT what had happened and i wish i had photo, was that the red domain formed at the tip of each node, in a rainbow shape shown in figure 1, and after each rainbow formed i increased volts, so each rainbow intersected with each other as in figure 2, it was during this that the rainbows started to form to a vortex shape and they started spinning "first them selves on their individual sides", figure 3 , then they started spinning amongst each other to form in to a sphere between the nodes, figure 4.

    Its after this something interesting happened, where around the sphere 2 green fins appeared, they were in a flame shape that had a bend much like as if it was in orbit, but did not spin(change position), figure 5. and that s what the whole thing looked like, (i kno im wrong with this) but thats what im calling it for now, a Quazar, since its the closest thing iv seen to it. http://www.mrwallpaper.com/wallpapers/cosmic-quasar.jpg

    However one thing that suggests that im wrong about that is the fact that i was only able to keep it formed for about 10 seconds, after that spent several minutes trying to do it again with no success , after giving up i released the air back in to my pot, while DE-pressurizing a green flame started in the bottom of my pot, and slowly raised and burned level all the way to the top of the pot, in a matter of 2-3 seconds, this did not com-bust nor noticeably impact my vacuum pressure, I expected the lid to blow off , but nothing of such. cos of that i am mostly blaming contaminates from shielding burnt off the wires, and just witnessing a simple fire. But would be most interested to hear your opinion of what happened and how i formed my "Quazar".
     

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  10. Dr_Doggy

    Dr_Doggy Well-Known Member

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    OK pretty colors , got it!

    But next Im trying to understand ionization energy, which as i understand is the amount of energy it takes to bump these electrons out of orbit, first i have problems measuring a gram of oxygen, so lets start simple with NaCl:
    Na = 500 KJ/mol = 5eV
    Cl = 1250 KJ/mol = 13eV
    so if i want to break down this compound I would go by the Na value rite? since it is the first in the compound?
    1 mol of Na requires 500KJ so thats what i need to dump in to my pot, but how?

    according to this: http://www.rapidtables.com/calc/electric/Joule_to_Watt_Calculator.htm
    If i am to dump 500KJ to get my mol of na i will need to insert power at 1.6KWatt for 5 minutes? or 800watts for 10 minutes?
    in order to set that value though i need to know 2/3 of the following values: voltage, current, resistance, but what is the best way to do this?
    i could use a volt divider to bring down the KV value for my voltmeter...
    but how should i get my other value , what would be easiest method, is it safe to put kv on my ammeter? and how to measure high resistance like that?

    Also what is the point of stripping a second electron?
    and with this energy level as an example what temperature can i expect in my core, so far the pot gets warm to the touch, but at the same time i show evidence of temperatures of over 800degrees on the inside?

    thanks!
     

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