High pressure tungsten incandescent light bulbs?

In summary, with increased pressure, tungsten has a higher melting point, as seen in the data on page 30 of the source provided. For example, at 45kBar, the melting point increases from 3422oC to 3700oC. This information is relevant to the efficiency of a 5800 K black-body, which would be 37% efficient if truncated. However, extrapolating this graph to a 300kBar light bulb would not be feasible, as the bulb would have to be made of steel instead of glass, and the pressure required (3000kg/mm2) may not be achievable. Additionally, the gas inside the bulb may turn to liquid, leading to more efficient heat transfer and
  • #1
James125
19
0
With increased pressure tungsten has a higher melting point. (source below page 30) 45kBar increases melting point from 3422oC to 3700oC.

http://www.nist.gov/data/PDFfiles/jpcrd55.pdf

An ideal 5800 K black-body, truncated would be 37% efficient.

http://en.wikipedia.org/wiki/Luminous_efficacy#Examples

So extrapolating this graph a 300kBar light bulb would be at 5800k and 37% efficient. I know this an extremely high pressure but would this theoretically work?
 
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  • #2
No, because you'd have to make the bulb out of steel, not glass. A steel light bulb won't work very well.
 
  • #3
Pressure works out to be around 3000kg/mm2. I'm not sure if it's even possible to hold that in...Also I'm not sure if the gas inside would turn to liquid in which case it would certainly conduct the heat much more effectively, which would transfer to the case.
 

1. How do high pressure tungsten incandescent light bulbs work?

High pressure tungsten incandescent light bulbs work by passing an electric current through a tungsten filament inside the bulb, causing it to heat up and emit light. The high pressure within the bulb helps to maintain the filament's temperature, allowing it to produce a bright, white light.

2. What is the lifespan of a high pressure tungsten incandescent light bulb?

The lifespan of a high pressure tungsten incandescent light bulb can vary, but on average it can last between 750-1,000 hours. However, this can be affected by factors such as voltage fluctuations and frequent on/off cycles.

3. How does the light output of high pressure tungsten incandescent light bulbs compare to other types of bulbs?

High pressure tungsten incandescent light bulbs have a high light output and produce a warm, yellowish light. However, they are not as energy efficient as other types of bulbs, such as LED or fluorescent bulbs.

4. Can high pressure tungsten incandescent light bulbs be used with dimmer switches?

Yes, high pressure tungsten incandescent light bulbs can be used with dimmer switches. However, it is important to ensure that the dimmer switch is compatible with the bulb and that the wattage of the bulb does not exceed the maximum wattage of the dimmer switch.

5. Are there any safety concerns with using high pressure tungsten incandescent light bulbs?

Like all light bulbs, high pressure tungsten incandescent light bulbs can become hot during use. It is important to handle them carefully and avoid touching the bulb while it is on. Also, make sure to turn off the power before replacing the bulb to avoid electric shock.

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