While Wikipedia describes the flow path as axial, I wonder if the path could be helical instead. Wikipedia explanation is described first in section 1, section 4 is for what could be the actual flow path, and sections 2 and 3 list the reasons for that. Section 5 is my question.
1. Usual high-level explanation
Wikipedia explains air flow in a jet engine this simplified way:
Flow path, Wikipedia, author: Jeff Dahl
Not obvious on the picture, there is a stator with vanes after each rotor, to create the pressure increase on vanes pressure side, and to straighten the flow for the next stage of the cascade, else there would be no compression and the engine would be an expensive fan. See this question for a picture showing the stators.
2. Taking into account blade and vanes
Usual depiction of the path, taking into account blades and vanes, is zigzagging, similar to:
The path above seems valid for motionless blades and vanes, ignoring blades are in rotational motion. If we dive into a bit more detailed explanation, the path would be refined like this:
Vanes pressure side is upward while blades pressure side is downward.
3. Taking into account blade rotation
With blades rotation, blades of the second stage do move while air is traveling across the first stage. While rotating, second stage blades deflect older air, which now exits the second stage using a vane which is lower than the vane it exited the first stage (during this time air of the first stage has reached the second stage, but is deflected by an upper blade, etc):
Air path is therefore spiraled a bit, the exact amount of the helical displacement depending of the ratio between air axial speed and blades angular speed. This is not necessarily the exact vane angular spacing (or a multiple of it).
4. Seemingly more consistent depiction of air path
If this was the correct way it works, then the overall flow would rather be helical than axial, something more like this:
5. Question: How blades and vanes impact overall air path? How the air path can be better explained, taking into account blades are not fixed?
I'm looking for some details, perhaps blade/vanes geometry and airspeed, not an over-simplified view.