Astrophysical rotating fluids

 


You may face rotating fluids in astrophysics when you are considering stars in binary systems: tidal effect usually locks the spin rotation of the stars to that of their orbital motion; when periods are short (typically less than a few days) the Coriolis force is controlling most of the flows inside the stars and the fluid is said to be rotating. More about that may be found in:
 

But stars may rotate alone because they are young and still have a lot of angular momentum of the cloud which gave them birth. Their period may be around one day which is very fast (the surface velocity is often not much less than the keplerian velocity). Sometimes they oscillate (they are then called Gamma Dor, Delta Scuti, Dzeta Oph etc...) and we wish to model these oscillations because  they allow us to understand their internal structure; now start the difficulties because such oscillations are much perturbed by the Coriolis force; you will now read: