COEFF_dt_Darcy

Default: COEFF_dt_Darcy = 1.0 The virtual time step size for the correction pressure computation in case of a Darcy term is present, is computed as \begin{align} \Delta t_\beta = \text{COEFFdtDarcy} \cdot \Delta t\end{align} See CorrectionPressureAlgorithm , v-- , and vp- for details, especially look for \( \Delta t_\beta\). Note: Actually, it makes sense to choose this value >= 1 only in the case of vp-. For v-- , it will big values of the Darcy coefficient %ind_betaDarcy% might cause instabilites if the nondimensionalized number \( \frac{\beta H}{U_0}\) is dominant compared to either the Strouhal number \( \frac{H}{U_0 \Delta t}\) or the Reynolds number \( \frac{\eta}{\rho H U_0}\) . In this case, COEFF_dt_Darcy can be used to limit the term \( \Delta t_\beta\) such that \begin{align} \bf{O} \left( \frac{\text{COEFF_dt_Darcy} \beta H}{U_0} \right) < \bf{O} \left( \frac{H}{U_0 \Delta t} , \frac{\eta}{\rho H U_0} \right)\end{align} Another way of keeping the stability of the simulation is the parameter DEBUG_GeneralParameter(37) .