ALE combine to frozen rotor ?

[frenchstudent]

hello !
I'm new on code saturne so thats why i'm coming to you.

My question is how can i simulate the fact that a fluide make move a solid (for me a propeller in rotation).
I know that with the ALE module you can simulate a solide translation and more, but i really don't know how to simulate a rotation

Actualy i made a simulation with frozen rotor, where my propelle turn with a fixed velocity, and a fixed fluide velocity.

Sorry for my english, and thanks for your answer !

Valentin

[Yvan Fournier]

Hello,

The "transient" turbomachinery model would be better than the "frozen rotor", but in any case, we would need to reverse the logic (i.e. compute the stresses on the surface, use those forces to determine the rotation velocity, then update the mesh). Currently, this model assumes a constant rotational speed, so some relatively simple changes in the code would be necessary to handle a variable rotational speed.

In any case, ALE will only be usable for small mesh deformations, so it is not adapted to modeling a rotor.

One possible solution to your problem would be to use a fixed velocity and time step turbomachinery option, for an initial estimate of the rotational velocity, and compute the forces on the propeller, so as to determine the torque and force at a given rotational speed. Doing this for different rotation speeds, you should be able to determine a characteristic curve (or portion thereof) for the propeller, allowing you to determine haw fast it rotates given the amount of work provided for each rotation.

Best regards,

Yvan Fournier

[frenchstudent]

Thanks for all !