TUFLOW 1D2D Boundary Configuration Guidance: Difference between revisions

Selection of a 1D timestep that is too large can cause instability. The <u>[https://docs.tuflow.com/classic-hpc/manual/latest/ TUFLOW manualManual]</u> includes some discussion on 1D timestep selection and courant number criterion. Conceptually a 1D timestep should be chosen to ensure a volume of water does not travel a distance longer than the shortest 1D channel within a model. For example, if the flow velocity and celerity is 5m/s and the 1D channel length is 10 metres, the 1D timestep should be less than 2 seconds. To provide some tolerance for faster flows associated with different flood events, a timestep of 1 second may be appropriate.