So I rigged up an airspeed sensor from old drone parts and made an adapter to insert the pitot tube into the fan housing. After calibration I ran the fan for a while and took readings, got around ~2m/s average. I cross checked this with a handheld anemometer and got 7.5kph which is about the same so it seems like that's probably reasonably accurate.
I'm not an HVAC person so I'm not sure which part of the housing I should use to calculate the CFM - the inlet (147mm) or the outlet (110mm). If anyone can assist who knows about HVAC calculations I'd really appreciate it.
As it stands I'm getting between 161-287CFM depending on which area I use. The fan I'm testing is rated to 186CFM on the box, so I'm assuming the lower of the two measurements it likely the correct one.
This puts it in the area of 10 air exchanges per hour for my home office, which is 25m3, about the size of a small bedroom. That would indicate it's working pretty well to run the air through the filter but it seems too good for such a basic device so I worry my methodology might be suspect.
Again, if you are familiar with these processes and measurements let me know as I'd love to get this right.
So I rigged up an airspeed sensor from old drone parts and made an adapter to insert the pitot tube into the fan housing. After calibration I ran the fan for a while and took readings, got around ~2m/s average. I cross checked this with a handheld anemometer and got 7.5kph which is about the same so it seems like that's probably reasonably accurate.
I'm not an HVAC person so I'm not sure which part of the housing I should use to calculate the CFM - the inlet (147mm) or the outlet (110mm). If anyone can assist who knows about HVAC calculations I'd really appreciate it.
As it stands I'm getting between 161-287CFM depending on which area I use. The fan I'm testing is rated to 186CFM on the box, so I'm assuming the lower of the two measurements it likely the correct one.
This puts it in the area of 10 air exchanges per hour for my home office, which is 25m3, about the size of a small bedroom. That would indicate it's working pretty well to run the air through the filter but it seems too good for such a basic device so I worry my methodology might be suspect.
Again, if you are familiar with these processes and measurements let me know as I'd love to get this right.