[Bldg-sim] supply air rate

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Sambhav,

There is a range of cfm/sf depending on type of space, etc. A really good
resource for them is a little book that ASHRAE publishes that has all kinds
of "rules of thumb" in it, although I just looked for it in their
publication catalog and didn't see it,

Anyway, it depends of type of space, space usage, whether it is an interior
or exterior space, etc., and seems to hover around 1 cfm/ft. It has always
made me wonder why the eQUEST default is 0.5 cfm/sf, because that number in
almost all cases will be too small. Since we're dealing with Q = 1.08 cfm
delta T a lot in our annual energy calculations this points to a high
probability that the hours of cooling/heating will be outside of their
throttling range. I almost always raise the cfm/sf right away when I start a
model.

Hope this helps,

Carol

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