So you know, those engine fans do rotate (though only as a flat, spinning disk)! What you're looking at is some sort of static ducting system, you see it a lot on these old low bypass engines - the MD80, for example, has the same. You can see them here:
http://cdn-www.airliners.net/aviation-photos/photos/3/2/2/1269223.jpg
And the same thing on an MD80:
http://www.trollabort.se/images/Bildbank/album/medium/PictActionMD80engine-037.jpg