You can simulate a model at any time by clicking the Run button on the Simulink® Editor.
The simulation runs from the start time to the stop time specified in the model configuration. While the simulation is running, you can interact with the simulation, tune parameters, stop or pause the simulation, and launch simulations of other models.
If an error occurs during simulation, simulation stops, and the Diagnostic Viewer opens to help you determine the cause of the error.
For more information on starting and stopping simulations, see Simulate a Model Interactively.