FLUENT can solve the conservation equations in a time-dependent manner, to simulate a wide variety of time-dependent phenomena, such as
Figures 25.17.1 and 25.17.2 illustrate the time-dependent vortex shedding flow pattern in the wake of a cylinder.
Activating time dependence is sometimes useful when attempting to solve steady-state problems which tend toward instability (e.g., natural convection problems in which the Rayleigh number is close to the transition region). It is possible in many cases to reach a steady-state solution by integrating the time-dependent equations.
See Section 25.3.2 for details about temporal discretization.