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Use an aerogel to fill the space inside the envelope of the lightbulb. It's insulating, and you get the frosted look too.
The aerogel filling will permit the lamp filament to be run at a higher temperature, increasing efficiency.
The aerogel will, in effect providing micro-cells of convection,
reduce evaporation from the filament and thus prolong its life.
The solid part of the aerogel will have to be some refractory material like alumina and the filling some inert gas, maybe krypton for the sake of the advertising tagline.
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It would also reduce the light output of
the bulb.
Better to buy Compact Flourescents that
are efficient, cheap, long lived and even
available in daylight colour temperature. |
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Micro-cells of convection...you do realize there's no convection in a vacuum? |
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Read the last praragraph,
ldischler, it is filled with Krypton. |
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And BrauBeaton, raising the temperature is exactly what this idea is on about. |
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I appreciate what you're trying to do, but the primary source of heat transfer is not conduction or convection but through radiation. Perhaps instead of insulation (which will do nothing except provide more chances of converting light into heat, which is not what we want), we can just coat the inside of a light bulb with a material that is reflective in the infra-red spectrum but clear in the visible spectrum. |
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//Read the last praragraph//
My point was, there's no convection in an ordinary light bulb. |
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1. You don't want to run the filament at a higher temperature, because this physical limit has already been fully exploited. In short, it would melt. |
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2. It doesn't matter how good an insulator you use, the light bulb would still get hot. Adding an insulator does not change the heat output of the light bulb. It would take longer to reach equilibrium, but the end temperature would be the same. |
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// 1. You don't want to run the filament at a higher
temperature, because this physical limit has already
been fully exploited. In short, it would melt. // |
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Halogen bulbs run their filaments at a higher
temperature (using the halogen gas to reflect the
infrared back to the filament), both refuting your
point and making both [neelandan]'s and
[Worldgineer]'s ideas unnecessary. |
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// 2. It doesn't matter how good an insulator you use,
the light bulb would still get hot. Adding an insulator
does not change the heat output of the light bulb. It
would take longer to reach equilibrium, but the end
temperature would be the same. // |
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The thermal power output will be the same. The
temperature difference will not. Why do you wear a
coat in the winter if what you say is true? |
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