I mentioned 5 ways of measuring flow, but perhaps I should have
eleaborated a bit on one or two of these:
Method 1). Pressure goes up with the square of flow, so if the pressure
you measure is 2x that in the data sheet, the flow is about 1.414 times
that. See my paper in QEX 'Predicting the Performance of Centrifugal
Fans' , Kirkby D. R., QEX, October 1997, pp 27-31.
Method 3) The resistor should heat the air, not the chassis. Hence don't
mount it on the chassis, but suspend it in the cathode compartment,
using the wires that power it. Hence my concern about safety and it
damaging the fan. I used thermocouples to make temperature measurements.
G8WRB
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