Which is the advantage in using a staggered grid? Is it alwayas the best method?

Thank you.

Matteo

A staggered grid is used for pressure and velocity cells to obtain convergent solutions where the fluctuations in the velocity and pressure, as well as the free surface instabilities need to be evaluated.

I think staggered grid is only valid for regular mesh(so-called structured grid).

I am using tetrahedral grid in 3D, and using colocated grid, it works fine.

A staggered grid is used to prevent pressure velocity decoupling which can occur on a collocated grid if certain measures are not taken.

pressure mode only occurs when you use the same low order of shape functions for pressure and velocity (velocity should be interpolated 1-degree higher than pressure due to NS equations) or when you use regular mesh.