VAV strange behavior

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I'm attaching a file which demonstrates something strange I recently
discovered. This is a quick wizard generated file with one change - on the
first floor, I specified minimum flow requirements as cfm/sf at the zone
airflow level for some of the zones. In the baseline model, all airflows
are auto-sized, and the actual flows to the spaces are equivalent with the
minimum airflows specified.

The parametric run: "Fan Flow specified" specifies the design airflow for
the fan for the VAV system on the first floor (the airflow is equal to the
auto-sized airflow in the baseline model). The reported design minimum flow
rates are the the same as in the baseline model, but a look at the SS-R
report shows that for the spaces where the minimum flow rate is specified in
cfm/sf instead of minimum flow ratio, the system minimum flow ratio takes
over. The spaces where minimum flow is specified as a minimum flow ratio
perform as expected.


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Joined: 2011-09-30
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