The local time step formulation for the pseudo time method is compatible with steady-state and transient cases that use a pressure-based segregated solver (SIMPLE, SIMPLEC, or PISO). Fluent computes a local pseudo time step size for each cell in the domain based your specified pseudo time Courant number and the flow scales [504]. In addition to the under-relaxation implied by the pseudo time method, implicit under-relaxation is applied by default for the momentum equation and other transport equations.

For details on applying the local time step method, refer to Local Time Step Method Setting in the User’s Guide.