Greetings, On Sun, 2012-08-19 at 04:52 -0400, Cody Firestone wrote: > FROM THE ARCHIVE > > > As "Critical Path" reference noted, another reason this cools air is > the "Bernouli" effect of speeding the air -- as a fan does, and as > Percival alluded to in his mention of ancient stone window cover > designs (which I'd like to know more about!) here, in this thread: > http://groups.google.com/group/hexayurt/browse_frm/thread/3108984409d21ac5?hl=en# > > > Percival, if you see this, can you tell me what those stone window > covers were called so I can research them a bit?
Thank you for reminding me. I went back to the builder, from whom I had heard about them long since, to ask about them. They were used in mosques in Cordova, which was then part of al-Andalus, in the 10th century, in places where they had lots of heat, but not much dust (or, apparently insects, or didn't care about the insects ...) and were carved stone, or stucco (or possibly wood, but we have no record of those anymore) my test showed that, indeed, moving air (generated by a fan, pointed sideways, aka not at the window) was cooler on the smaller-holed side than it was on the larger-holed side (the side with the fan on it) using identical thermometers. (I switching them, to make sure it wasn't a function of the thermometer, or my ability to read it.) I also did a form of the vent test, with an actual ger (what most people call yurt) which I live in for Pennsic every year. Having vents (basically lifted cloth) at the bottom, around the house, and having the roof-hole open, or with a chimney from the roof-hole upward (we tried both ways) had it much cooler in the ger, yes, but a piece of cellophane hung from a pencil showed air moving _in_ through the vents, and out through the roof hole or chimney, not vice-versa. Percival -- You received this message because you are subscribed to the Google Groups "hexayurt" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/hexayurt?hl=en.
