High CFM Fan Airfoil: Expert Guide

[HotFurnace]

Hi airfoil experts,

I brought two high speed fan for magnetron cooling, and upon destroying one due to my mishandling of the stuff, I found out these fan have surprising nice airfoil. See the pictures and you will understand their construction.

The rotor part looks just like a normal air flow computer fan, but in addition, there is a stator part, right behind the rotor. I think it is for conversion of the circumferential component of the velocity into axial component, but if is so then why don't they use this design instead? (see the animated gif)

And why manufacturer decided not to incorporate a stator airfoil in addition to the rotor's in a usual computer fan? They seem to reserve the stator for high CFM fan only, but even then some still don't have them. For cost saving maybe?

 

[russ_watters]

Cost and effort, probably.

 

[trurle]

And why manufacturer decided not to incorporate a stator airfoil in addition to the rotor's in a usual computer fan? They seem to reserve the stator for high CFM fan only, but even then some still don't have them. For cost saving maybe?

Looks like volume saving. Twin rotor would require thicker case to keep both sets of plastic blades rigid enough.

 

[256bits]

Does one really need the stator if one if just blowing air?
So what if there is a swirl to air.

 

[AeroGeek]

Hi airfoil experts,

I brought two high speed fan for magnetron cooling, and upon destroying one due to my mishandling of the stuff, I found out these fan have surprising nice airfoil. See the pictures and you will understand their construction.

The rotor part looks just like a normal air flow computer fan, but in addition, there is a stator part, right behind the rotor. I think it is for conversion of the circumferential component of the velocity into axial component, but if is so then why don't they use this design instead? (see the animated gif)

And why manufacturer decided not to incorporate a stator airfoil in addition to the rotor's in a usual computer fan? They seem to reserve the stator for high CFM fan only, but even then some still don't have them. For cost saving maybe?

The configuration (in gif image) posted is likely or ideally used in gas turbine/aircraft engines since the air passes through a series of rotor and stator eventually achieving a better pressure ratio for the combustion, here in this fan using that kind of configuration will make it bulkier and obviously increases the cost. Adding a stator at the end guides the flow, they act like guide vanes.