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Solar chimney math

 
gardener
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Location: Rocky Mountains, USA
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So, I'm looking for leads.

What math do you need to figure out the size and shape of solar chimney you would need for cooling a given area?  I'm guessing the volume of the chimney is important, the solar collection area of course, and probably a lot more.  Where does a person start when it comes to figuring all this out?
 
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Hey K,
with a quick search I found the following article, with a lot of references (in chapter 3.3). https://www.sciencedirect.com/science/article/pii/S1364032120309539#bib26
 
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This is a simple formula, originally from an old solar greenhouse book by Bill Yanda:

     cfm = 16.6 Av sqrt((Tu-Tl)h)

Tu is the temperature at the top (outlet).
TI is the temperature at the bottom (inlet)
h is the height between, in feet
Av is the smallest cross sectional area of the vent, in square feet.
16.6 is a constant

It could also be written as:   CFM = 16.6A sqrt(HdT)
with A as Area,
H as the Height,
dT as deltaT (the temperature difference, top(outlet) minus bottom(inlet))

It is a bit different from some other formulas, but simple and seem to work well enough.


 
I think he's gonna try to grab my monkey. Do we have a monkey outfit for this tiny ad?
A rocket mass heater is the most sustainable way to heat a conventional home
http://woodheat.net
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