eric dainty has practical test data showing improved thrust using 8 (i think) rotor blades.

no idea how many stator blades he used...im pretty sure they went unchanged.

his goal was static thrust though.

IMO you'd use the biggest engine possible with any fan design. i.e. always size the fan to the engine.

for a k &b 82 it'd yield around 3 hp wouldnt it?

since the dynamax gobbles up 4.8 hp at 23k or so and gives around 15lb at the effluex side of the fan. (this is actually true, wshen measured directly next to the cylinder head).

by the time it moves down a small thrust tube, it's more like 12-13lb.

now, 15lb at 23k means the thrust coefficient is found by:

Thrust = Thcoeff x (RPM/10000)^2

therefore 15 = tc x (2.3)^2
therefore tc = 2.84

assuming that 4.8 hp is absorbed at this rpm.

The power coefficient is

Power = Pcoeff x (RPM/10000)^3

4.8 = Pcoeff x (2.3)^3

Pcoeff = 0.3945

So, rpm for 3hp is 19,600.


the trick here is to ensure that your k&b gives 3 hp at 19,600 rpm.
thrust at 19600 is 11lb at efflux side.

and so on..