Stator inlet angle in turbomachine?

[Nick1]

Hello,

I am wondering about the following action in a stator:

If the inlet angle in a stator is B, and the outlet angle is -B, what exactly is happening? Axial vlocity should be constant, and so should the relative velocities except being mirrored and i am asuming infinitely thin blades.. Can i somehow know how the corss sections of the inlet and outlet to the stator relate to each other?

My thought is that since it is a stator, all static properties are the same therefore the density will be the same. And since the axial velocity and mass flow are the same, the area should also be the same, meaning A0/A1 = 1. Am i thinkng correctly?

If this was a rotor, would it be correct to say that the reaction degree is 0?

 

[Achy47]

Hello,

Great question! In a stator, the inlet and outlet angles are typically measured relative to the axial direction, which is the direction of flow. So, if the inlet angle is B and the outlet angle is -B, this means that the flow is being turned in the opposite direction by the stator. This is known as a negative or reverse flow.

In terms of the cross sections of the inlet and outlet, they are related by the conservation of mass. As you mentioned, the density and mass flow are the same, so the areas must also be the same. This means that the ratio of the areas, A0/A1, will be equal to 1 as you stated.

If this was a rotor, the reaction degree would indeed be 0. This is because in a rotor, the flow is being accelerated in the same direction as the rotation of the blades. In contrast, a stator is designed to slow down the flow and redirect it in a different direction.

I hope this helps clarify things! Let me know if you have any other questions.