4 ms·

Ward certainly believes in his product, claiming publicly that it could have prevented the space shuttle disasters. 'Starlite has a Q-value [an energy absorptio

Ward certainly believes in his product, claiming publicly that it could have prevented the space shuttle disasters. 'Starlite has a Q-value [an energy absorption rating] of 2,470. The space shuttle tiles have a Q-value of 1.' Not only that, but because Starlite is so lightweight – 1mm thick, compared to 75mm for the space tiles – it's actually '2,470 x 75 times better'. http://www.telegraph.co.uk/technology/5158972/Starlite-the-nuclear-blast-defying-plastic-that-could-change-the-world.html http://www.telegraph.co.uk/technology/5158972/Starlite-the-n... What is a "Q-value" in this usage?

jzwinck 13y ago
Q is the heat transfer rate; see http://en.wikipedia.org/wiki/Heat_transfer_coefficient http://en.wikipedia.org/wiki/Heat_transfer_coefficient
- deleted 13y ago
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- throwaway_yy2Di 13y ago
  Thanks! But, if that's the case, a higher value means a worse insulator, so why would he brag about that? (It's also a dimensionful quantity, but the reported value has no units -- maybe it's relative to some specific value...)
  - throwaway_yy2Di 13y ago
    I think it's more likely to be a measure of heat absorbed, rather than heat transferred across a boundary. (The Telegraph's wording is "an energy absorption rating"). Starlite is apparently ablative; if this means an endothermic phase change -- the organic polymers vaporizing, without combusting -- it could absorb an extremely large amount of heat. A space shuttle tile is non-ablative (I think?), and can absorb heat only by increasing temperature.
Elrac 13y ago
> but because Starlite is so lightweight - 1 mm thick Just what about a substance determines how thick it is? How thick is concrete, then? Glass? Is there a reason Starlite can't be manufactured 75 mm thick, and would it then not be even more amazingly effective? Or alternatively, what's the thickness value for concrete? Glass? What's the Q-value of 75mm of paper tissue?

jzwinck 13y ago

Q is the heat transfer rate; see http://en.wikipedia.org/wiki/Heat_transfer_coefficient http://en.wikipedia.org/wiki/Heat_transfer_coefficient

deleted 13y ago
[deleted]
throwaway_yy2Di 13y ago
Thanks! But, if that's the case, a higher value means a worse insulator, so why would he brag about that? (It's also a dimensionful quantity, but the reported value has no units -- maybe it's relative to some specific value...)
- throwaway_yy2Di 13y ago
  I think it's more likely to be a measure of heat absorbed, rather than heat transferred across a boundary. (The Telegraph's wording is "an energy absorption rating"). Starlite is apparently ablative; if this means an endothermic phase change -- the organic polymers vaporizing, without combusting -- it could absorb an extremely large amount of heat. A space shuttle tile is non-ablative (I think?), and can absorb heat only by increasing temperature.

Elrac 13y ago

> but because Starlite is so lightweight - 1 mm thick Just what about a substance determines how thick it is? How thick is concrete, then? Glass? Is there a reason Starlite can't be manufactured 75 mm thick, and would it then not be even more amazingly effective? Or alternatively, what's the thickness value for concrete? Glass? What's the Q-value of 75mm of paper tissue?