Looking for the exact fan for the calorimeter, I began also comparing published air flow rates for similar fans.
4 m/s air velocity in a 65 mm diameter pipe, at Standard Pressure seems to work out to 112.5 28.2 cfm. (more than my bathroom fan)
Edit: I caught my previous error above. The cfm of the fan seems to be right on the money for the air flow rate claimed compared to higher-end fans rated for 12V 5W.
Most fans in the projection design (side outlet) 12V 5W range seem to only be rated for 10 to 30 cfm.
So far, this one in the image below has the highest listed flow rate that I have been able to find the flow rate for.
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