Hello all, I have been trying to figure out how to make/assemble some evacuated vacuum solar tubes,and was hoping to find a few answers.I work with pyrex and do some scientific glassblowing. I know that using a vacuum pump is the way to evacuate the space between the two tubes,but am trying to get around using the vacuum set-up mainly for financial reasons-and I am just experimenting right now.My main question that I hope someone can help me with is : Can a relatively low pressure vacuum be used, and work well overall for thermal insulation? I assume it would be better than having no vacuum. First, I hope this description is not too confusing! --The type of vacuum would be achieved by heating the two glass tubes (they have been put together,with a small hole left that would normally be used to evacuate the tube; to keep the pressure equalized) up to around 1000*F, and then closing the small hole that would seal in the vacuum between the two tubes, while hot. I have noticed when doing things similar to this,the sealing up of this hole will get sucked in if the glass temperature is dropping; hence there is some sort of vacuum that is created, from the space being very hot when sealed. I am curious how relevant this vacuum would be for thermal insulation. By the way, Peter G. and Phillip Wolfe, thank you for responding to my inquiries about a month ago on green jobs in RE,so far they have been a guiding light for me. :-) Thanks for any insight or links to help me figure out this vacuum question,and I hope it wasn't confusing the way that I explained it. -Chris Davidson _______________________________________________ Biofuel mailing list [EMAIL PROTECTED] http://wwia.org/mailman/listinfo.cgi/biofuel
Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuel archives at Infoarchive.net (searchable): http://infoarchive.net/sgroup/biofuel/
