.. _section-5.3.6: Check Valves ~~~~~~~~~~~~ |SAS| contains a simple check valve treatment in which the user can specify the valve orifice coefficient as a function of coolant flow rate. Every time step an orifice coefficient (:math:`G_2` in :eq:`(5.3-35)`) is re-set using a user-supplied table of orifice coefficient vs. normalized flow rate, with a flow rate normalized to its steady-state value. Other than the variable orifice coefficient, a check valve is treated the same as a pipe, as described in :numref:`section-5.3.3`.