FBWNDR wrote:
On Jan 24, 11:52 am, dpb wrote:
dpb wrote:

...

What did you use for the pressure/density for the cfm calculation you
did? Where did you get that performance figure and does it match theirs?
That is, specifically, if you used STP I'd expect actual to be higher by
fairly significant factor depending on specifics of draft design...
....

I did use standard pressure and temperature for the CFM calculation. I
would assume that the fan's rating is also given as standard pressure
and temperature. And I also assumed perfect combustion, and so I
determined how much wood (at 45% moisture) could be theoretically
combusted per hour with an air input of 75 cfm. ...

What would you get if you consider combustion air at intake of (say) 20F
or so? That density difference, while I didn't look it up, would be
moderately sizable I'd think.

Not sure, seems like 45% might be a little pessimistic on moisture, too,
maybe? I don't have data for seasoned firewood, just a thought.
Being no trees around here, the fad is the corn-fed boilers around here.
If one had the grain anyway w/ the automated feeders that seems to
make some sense to me altho larger producers are going to the waste oil
and/or the on-farm small (relatively) capacity biodiesel conversion if
they also have soybeans as a normal rotation. I've heard of a couple
that estimate they're replacing all their off-road diesel requirements
from about 8-12% of their production acreage depending on the annual yield.

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