Hi Alex, The solver type refers to how you approach solving the given equations. In the case of incompressible Navier-Stokes, there are different approaches. The most common is the velocity-correction scheme (VCS) and it's derivatives. However, there is also a coupled solver for the monolithic system. The TimeIntegrationScheme refers to standard time-stepping schemes. This includes Runge-Kutta, backwards difference formula (BDF), Euler-forward/backward and more specific schemes such as the Implicit-Explicit (IMEX) schemes. You can find a number of examples in e.g. the ADRSolver tests. Your specific combination VCS + IMEXOrder2 leads to a second-order accurate VCS. An alternative might be the first-order accurate scheme via IMEXOrder1. Best wishes, Henrik ________________________________ Von: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> im Auftrag von Alexander Schukmann <alexander.schukmann@protonmail.com> Gesendet: Dienstag, 9. Juli 2024 16:33 An: nektar-users@imperial.ac.uk <nektar-users@imperial.ac.uk> Betreff: [Nektar-users] Velocity Correction Scheme and Time Integration Methods This email from alexander.schukmann@protonmail.com originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list<https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email stamping for this address. Hello everyone, would somebody be so kind to briefly explain to me what exactly the TimeIntegrationScheme flag does in the session file when there is also a solver type that needs to be set? The Velocity Correction Scheme is a time integration algorithm in itself, so why exactly is setting TimeIntegrationScheme to e.g. IMEXOrder2 needed in addition to choosing VCS? All the best Alex Sicher versendet mit Proton Mail<https://proton.me/>.