segragated solver vs couple solver
 

Hi!
quick question. Should I expect different results if I run one same geometry with segregated solver and couple solver?? So the only difference between both run would be the solver (turbulence model, mesh, etc the same for both cases), and of course, assuming that both cases converge.
Why is the coupled solver recommended for external aero cases, even if it is an incompressible simulation??
Thank you very much in advance!!

It depends, coupled solvers typically need different convection schemes. And even for equal schemes the coupling plays a relevant role.

So, in general, you can only expect similar results within the respective accuracies (equal to the naked eye). But as the equations are non linear, you can't exclude that, in certain cases, some effects of one solver will drive the solution away from the other.