Self-excited oscillation study in grille-cavity flow on floating nuclear power platform

In order to investigate the self-excited oscillation characteristic of flow past the inlet and outlet of cooling water systems on floating nuclear power platform, a numerical study in grille-cavity flow with suction and drain is carried out. A back pressure condition is set on the side wall of the cavity to simulate the suction and drain conditions. By varying the incoming flow boundary layer thickness and back pressure value, the self-excited oscillation characteristic in grille-cavity flow with suction and drain is studied. As calculations show, the boundary layer thickness has little influence on the oscillation frequency. The strength of self-excited oscillations gradually decreases with the decrease of back pressure, but the frequency does not change much. When the back pressure reduces to a critical value, the self-excited oscillation phenomenon disappears finally.