I grew up in the Hot Hot South under an attic fan and no A/C. Would hate to go completely back to that mode but evaporating sweat assisted by a steady breeze ain't all bad. Even after the folks got Central Air my Papa would turn it off and flip on the Attic Fan. He'd say "we're tradin wind and savin money"
then he'd add "not to be confused with breakin wind and smellin' funny."
.................... Some will prob think this whole thread is broken wind and hot air.
I have spent enough time working in trailers without power just praying for some breeze. So old John's post caught my attention.
Originally Posted by Pahaska
We have two cats in the trailer. In case the power goes off and we lose the AC, I set our Fantastic Fans to come on and circulate air for their safety. ~~<snip>~~ My new trailer has out-blowing fans only and does not support through-circulation with the windows closed for security.
First I'm taking this to mean that security is a factor of the windows being closed by you. Not of having out-blowing Fantastic fans.
And I am reading this to mean that if you could crack open window/s that the "out-blowers" (updraft) system would work like an attic (whole house) fan and draw air in from the window and out the fan port thus creating the circulation stream.
This assumption leads me to a number of curiosities which my limited grasp of thermal and air flow science cannot sort out. However I am confident that some of you scholars can help.
(Assuming in all cases that you have an out-flow fan running.) Is there a marked advantage to having the in-flow air forced (by the reversed fan) down into the trailer as opposed to being drawn in thru an opening such as a window? And is the size of each in-flow opening a critical factor or is the position in the trailer more important? i.e. if you have a 200sq.inch vent vs a 200sq.in. combination of window openings with no mechanical assistance are the (comfort and exchange) results the same even though the windows are lower in the trailer? and with the fan assistance at the roof vent is there an improvement or difference in the interior effect i.e. does the fan assist increase the amt of air that can enter the 200sq inches and if so does this affect comfort at person level (as opposed to ceiling level)?
When the Fantastic Fan is blowing downward does it blow hard enough to force the air-stream down to floor? Or would the air just follow the ceiling line forming a stream in at the down-flow fan and along the ceiling and out at the up-flow fan? Of course hot air rises and it would join into the stream and there would be some turn over effect.
For simple air transfer to bring in fresh air it may make no difference, but for the pleasant effect of a breeze assist on an occupant I guess we need open windows and maybe more than one fan in the up-flow mode???
Would turning on the furnace (fan only) and the A/C (fan only) if that is even possible, lend anything to the experiment?
Now just to make this all quirkier, would there be any advantage in having a vent (closable) in the floor of the trailer? I am assuming the outside ambient air temp may be a bit cooler in the shade of the under carriage as opposed to that along the roof.
And what if this floor vent contained some sort of evaporator core that could be filled with dry ice.....hmmmmn???
Alright class I would like your reports no later than mid semester.