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Ted Crilly February 17, 2005 19:41

Age of Air In Star-CD
hello star-cd users

is it possible to calculate the age of air as part of the starcd run,

i guess i must use scalar for my inlet source in the room,

i'm looking to investigate ventilation efficiency for different hvac options in a room, to find the domain average and distribution of air age in the space.

any help appreciated here



Mike February 19, 2005 20:50

Re: Age of Air In Star-CD
You can compute the age (or residence time) by adding a passive scalar with a user-defined source term of 1/density. This will measure residence time in seconds.

You should check that the solution method of this scalar is 'transport' and you should give it diffusion coefficient of zero. You can't entirely eliminate diffusion but you should minimize diffusion of this scalar.

I don't see why you need a scalar for your inlet source.

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