A few Computational Fluid Dynamics (CFD) codes implement the so called PISO (Pressure-Implicit with Splitting of Operators) algorithm for pressure-velocity coupling.

My concern is what is actual temporal order of accuracy of the algorithm?

It probably isn't enough to discretize time-dependent term in transport equations by second order algorithm (like second order Backward-Euler - BDF2), since we still use mass fluxes from the last time-step in the momentum equations?

Any suggestion of the papers that deal with this topic is welcome, or something relevant to this topic from projection/operator-splitting methods that would help to find an answer.

  • 1
    $\begingroup$ Don't cite me on this, but if I recall correctly, the PISO approach is second-order accurate in time because of the second step that corrects the momentum equation with the new mass fluxes. However, I am not fully sure of this, I'll try to find a reference. $\endgroup$
    – BlaB
    Mar 15, 2021 at 2:31
  • $\begingroup$ the order of the time depends on the "scheme" used for the time derivative term. $\endgroup$
    – ztdep
    Jul 20, 2023 at 8:00


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.