Steady state detection for fluid dynamic instabilities

Fluid instabilities are characterised by a critical parameter for their onset, an exponential growth phase and a saturated state. The latter may be a steady, periodic or highly fluctuating flow. Investigating a certain instability, large parameter spaces have to be explored by hundreds of simulations, e.g. for finding the mean velocity of the saturated flow. Such parameter studies can crucially be simplified, if the user does not have to specify the simulation time. For this purpose, we present a steady state detection system for OpenFOAM. It terminates simulations automatically if the steady state is reached.