Stability analysis of a uniformly heated channel with supercritical water

The thermal-hydraulic stability of a uniformly heated channel at supercritical water pressure has been investigated to help understand the system instability phenomena which may occur in supercritical water nuclear reactors (SCWRs). We have extended the modeling approach often used for the stability analysis of phase change systems to supercritical pressure operation conditions and have developed rigorous new non-dimensional groups for the stability maps. We have also shown that while density-wave oscillations (DWO) can occur, Ledinegg excursive instabilities and pressure drop oscillations (PDO) will not occur in supercritical water systems. The linear stability characteristics of a typical uniformly heated channel were computed by evaluating the eigenvalues of a one-dimensional model. An analysis of non-linear instability phenomena was also performed in the time domain and the dynamic bifurcations were evaluated.