Re: TECHMAIL: Vacuum-Jacketed Pipe

From: <Christopher>
Date: Mon Jul 03 2000 - 11:14:00 EDT

>The vacuum seal prevents heat loss due to convection,
>conduction, or radiation.

Um...actually it only reduces loss due to convection and conduction, since the vacuum isn't a perfect vacuum. The vacuum has no effect on radiation which works best in a vacuum. The sun couldn't warm the earth otherwise. As luck would have it at radiation is small at low ambient temperatures

Christopher Wright P.E. |"They couldn't hit an elephant from <a href="/group/PipingDesign/post?postID=EBkODfSnxcGlyXODJaBnxlTOD2pvxmxB9b-ewPmvTZJ1W-BdqBvAPPTIf2URyrXDkUTP_dM--o0WUgU">chrisw@skypoint.com</a> | this distance" (last words of Gen.

___________________________| John Sedgwick, Spotsylvania 1864)

<a href="http://www.skypoint.com/~chrisw">http://www.skypoint.com/~chrisw</a> Received on Mon Jul 03 11:14:00 2000