Characteristics of fluid and pressure oscillations induced by steam injected through a vertical blow down pipe under different vessel pressures

An experimental study has been conducted to investigate the characteristics of condensation oscillations induced by steam injected through a vertical blow down pipe. The inner pipe fluid oscillation phenomenon was observed at lower steam mass flux and water temperature conditions when chugging occurs. The inner pipe steam-water interface oscillation amplitude increases with the vessel pressure and decreases with steam mass flux and water temperature. The effect of the vessel pressure and steam mass flux on the interface oscillation frequency is prominent. The boundaries of the chugging condensation under different vessel pressures were identified. The pressure oscillation intensity in the pipe increases with the vessel pressure and decreases with the steam mass flux and water temperature. But in the pool, it first increases and then decreases with the water temperature. The peak values of the dynamic pressure were intensified by higher vessel pressure.(c) 2022 Elsevier Ltd. All rights reserved.