| Abstract: | Water hammer due to steam bubble collapse when cold water is admitted to vertical upward flowing, vertical downward flowing, and nominally horizontal pipes has been studied both experimentally and analytically. The work in horizontal pipes included a study of the effect of a slight downward inclination, a slight upward inclination, and the length of the pipe on the initiation of water hammer. Stability maps showing the combinations of filling velocities and liquid subcooling that cause water hammer and those which do not for each flow geometry were obtained from experiments. Analytical models were developed to predict those stability boundaries in the stability maps. All these models were tested with experimental data. Based on the verified models, a step-by-step approach for each flow geometry is presented for plant engineers and designers to follow in avoiding water hammer induced by steam bubble collapse. |
