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FlameBulb

Electrolysis-Driven Flame in Standard-Sized Compact Sealed Bulb
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This is the lightbulb for those who long for gas-lighting, and are tired of incandescent bulbs that try to fake it.

The base is fitted with a rectifier (for converting AC into DC) and a small reservoir of water. It's purpose is to split the water in to hydrogen and oxygen. It is thermally insulated from the rest of the bulb.

The "filament" is made from the metal of your choice (tungsten for white, strontium for red, copper for green, etc.). The hydrogen and oxygen are burned, heating the filament. Both the filament and the flame are visible.

The shell of the bulb is made of shatter-proof and heat-resistant glass. The water vapor from the burning of the hydrogen and oxygen is condensed and reclaimed at the base.

The FlameBulb packaging will feature the obvious legal disclaimer "Warning: Flames are Hot. Please do not touch the bulb while operating"

(FlameBulb 2 will feature an active water reclamation pump, thus enabling the bulb to be installed in any orientation).

cowtamer, Feb 12 2007

AC Electrolyser AC_20Electrolyser
Recent HB discussion [csea, Feb 14 2007]

[link]






       I'm not sure that would work. To have a fire, the burning has to be slow enough to sustain it by igniting the rest of the fuel (before the currently burning part burns out). I think hydrogen would burn too fast to keep a constant flame. You would get a series of tiny explosions, if you have an ignition mechanism (sparks, pilot light (defeats the purpose of thehydrogen flame), or heated wire), or just one explosion as all the mixture inside the bulb ignites, and after that burns out, there would be nothing to ignite the gas when the bulb fills up again.
Veho, Feb 12 2007
  

       Good point. I think what you would have to do is have a small hydrogen reservoir that acts as a buffer, and then release it slowly from a nozzle and past the heated ignition wire.   

       How fast the hydrogen and oxygen are formed is simply matter of engineering (surface area of the electrodes, how much current you're passing through the water, etc.)
cowtamer, Feb 12 2007
  

       This is probably not going to be energy efficient at all. I know electrolysis is about 10% efficient, and even less of that is going to become light. (On the other hand, this would double nicely as a heater :) )   

       But the point is to have a real flame without ever having to replace fuel...
cowtamer, Feb 13 2007
  

       I really like the general notion of this idea. + But I'm unclear as to why it's necessary to rectify the AC to DC. If you're going to burn the resulting gases, why separate them and then recombine?   

       I've seen two types of flickery flame bulbs, one like [bigsleep] has linked, which (I think) relys on a magnet and a loose filament to produce the flicker, and another (older) type, which is like a neon bulb, with perforated electrodes. It produces light by exciting a gas plasma. The heat of the plasma causes the hot spot to move chaotically, as a flame flicker. Both seem to work fine with AC current.
csea, Feb 13 2007
  

       You need to rectify the current in order to get electrolysis (AFAIK you can't do electrolysis with AC). Flame bulbs are nice, but they don't actually have a real flame inside.   

       Admittedly, this would be more of a scientific toy/novelty item...   

       (I'm going to see how far the idea can be milked...an indoor grill comes to mind...)
cowtamer, Feb 13 2007
  

       //You would get a series of tiny explosions//

But only if well mixed. With hydrogen bubbling up, separated from the oxygen bubbling up, and with an initial excess of oxygen, the hydrogen will burn continuously at the water surface, which is also where you have the coil of wire to be heated to incandescence.
ldischler, Feb 13 2007
  

       I wonder if that hydrogen burning at the surface would have the same look as a plate of burning ethanol?
bungston, Feb 14 2007
  

       //You need to rectify the current in order to get electrolysis (AFAIK you can't do electrolysis with AC). //   

       Nonsense! AC is no more than time-varying DC. An AC current will generate both H2 and O2 at both terminals, pre-mixed. One has to be careful that the electrodes don't erode in the process.   

       There was a good discussion of this on the HB not long ago. [link]   

       PLEASE DO NOT TRY THIS AT HOME without considering extreme safety measures. In particular, avoid using wall outlet current directly, and be sure to isolate the power with a transformer, and limit the current. Producing a mixture of H2 and O2 gases can be quite dangerous.
csea, Feb 14 2007
  

       //PLEASE DO NOT TRY THIS AT HOME //

Don't worry. We never actually build anything.
ldischler, Feb 14 2007
  

       lpf, hydrolysis zzzzzzzzzzzzzzzzzz.
quantum_flux, Feb 14 2007
  

       Would have to have some safety device to prevent the bulb from exploding, however shatter resistant. "Hey tommy, don't touch that bu...*bam*"
cpf, Feb 17 2007
  
      
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