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Old 09-18-14, 10:13 AM   #9
AC_Hacker
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Quote:
Originally Posted by Zwerius View Post
...First of all, you need a quite deep vacuum (<0,1 mbar or < 10Pa) and that's not so easy to achieve with standard vacuum equipment...
I would be interested in discussing this idea...

Zwerius, do you think that the phenomenon of vacuum insulation only occurs at <0.1 mbar? This would be what is known as a 'step function'.

It seems to me that there would be a gradient of insulation improvement as vacuum levels became greater.

For instance, a micron gauge is an instrument that is commonly used in refrigeration work to measure vacuum levels. The principle of operation is that there is a direct relationship between variation of heat flow across a variation of vacuum level. The micron gauge uses a very small heat source and a precision thermocouple is used to measure the changing heat flow as vacuum levels change.


As another example, taken from Aerogel technology, is a graph taken from THIS_PAGE that illustrates this varying relationship.



My point is that a person who is working with relatively unsophisticated equipment actually can realize very useful improvements in insulation, even if they do not achieve the theoretical maximum.

In short, yes I do believe that it is possible to DIY your own useful vacuum insulation.

Best,

-AC
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Last edited by AC_Hacker; 09-18-14 at 10:23 AM..
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