I need a way to move air which is somewhere in between a compressor and a fan: something along the lines of 20-40 cfm at 2-3 psi (500-1000 liters/minute at 10-20 kPa).
Typical small compressors (of the right power rating) seem to be approx 0.5 cfm at 30 psi. Typical centrifugal blowers are approx 60 cfm free flow but only 0.05 psi max static pressure.
I'm having trouble visualizing what I need, let alone sourcing it. Leaf blower? Shopvac? Supercharger? Do I want a piston pump, diaphragm pump, screw compressor, turbopump, some type of higher pressure centrifugal fan, or ???
For this application energy efficiency at the described operating point is most important; size/cost/noise is much less important. UPDATE It also needs to be oil-free.