Is the local mean age of air is always equal to the nominal time constant in cases with multiple inlets and outlets?

03 March 2021 1 7K Report

I try to calculate the mean age of air for a four-sided windcatcher. I know that in the exhaust, the local mean age of air is always (also in the case of a short-circuit flow) equal to the nominal time constant. Is this condition true for cases with multiple inlets and outlets?

Stuart Arthur Harris

It would depend on the time scale you are using. If the outside air is moving, this should be logged for speed and direction which can then be compared with your data to look for differences..

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