How does Fluent calculte the velocity from pressure?
 

Hello everyone,
the case that I'm simulating has a pressure inlet type and an outlet pressure type.
But the thing that I don't get is how can Fluent calculate the velocity from pressure ??
Please, can someone explain to me this!!!
and if there is any paper that can help me to understand this, please let me know.
I'll be so glad for any comments or answers from you
Best regards;
Dounia