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Why are there no stators behind the fan? At least, I've never seen any turbofan design that has stators right behind it. (Here is the latest turbofan I've looked at, the CFM56. Cutaway part starts around 00:35.)

The purpose of stators is to redirect the airflow to be mostly axial. Without them, the air would be spiralling too much.

The fan is the biggest compressor so I would think stators are needed there more than any other place, but apparently that's wrong. I just do not know why it's wrong.

Edit: Yep, there are stators there after all. Just because they're not shown in a video doesn't mean they aren't there. Oh well.

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    $\begingroup$ I'm not sure your premise is correct. AFAIK, turbofans do have stators in the bypass flow. If you go through the cutaway video you link to frame-by-frame, you can see them. $\endgroup$
    – Thomas
    Sep 6 '17 at 6:43
  • $\begingroup$ This video is a bit misleading (higher resolution video). At 0:54, by some difficult to understand camera displacement, the booster stators start contra-rotate and the rotors become stationary except the fan. At least, the booster rotors and the fan should be synchronous (N1). $\endgroup$
    – mins
    Feb 2 '20 at 13:39
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enter image description here

Right behind the fan you can see the stators.


enter image description here

Here they are from behind.


enter image description here

Here is the fan removed, with the (1) fan stators (outlet guide vanes), and (2) inlet guide vanes for the compressor (booster).


Just like I wrote here:

On the funny side, here's a thumbnail from RR's own YouTube channel, absolutely bonkers exhaust. Don't trust illustrations.

enter image description here
(CFM56-5A manual)


You can watch the fan removal here: CFM56 7B Fan Blade Removal

Below is the stator assembly for the GE90:

enter image description here


Image sources:

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  • $\begingroup$ Where is the inlet guide vane? I have read it is placed before the rotor of the compressor? Is inlet guide vane and stator after fan you mentioned same? $\endgroup$
    – Auberron
    Jun 30 at 3:29
  • $\begingroup$ @Auberron: Ctrl+F "inlet guide vane", it's in the answer ;-) $\endgroup$
    – ymb1
    Jun 30 at 21:45
  • $\begingroup$ Picture of OGV for a GE90. Source. $\endgroup$
    – mins
    Jul 20 at 17:07

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