Leak testing was carried out with Hot Water and Steam Leak Testing System for saturated vapor and sub-cooled liquid with 4 different channel geometries.
The pressure drop between the main Pressure vessel and leak testing plate was estimated by Lockart-Martinelli correlation for two-phase pressure drop. Theoretical critical flow models of Moody and Henry-Fauske has been tested with experimental results, and Moody model was found to slightly underestimate the critical flow rate at high quality Stagnation condition, while Henry-Fauske model agreed well with the experimental value in the case of sub-cooled liquid.
As the leak rate increased, the dominant event amplitade and the ringdown count rate of Acoustic Emission increased. But it was shown that the evaporation and collapse of cavity played a major role on the Acoustic Emission activity. The burst type signals of 15-45 KHZ were found to be the most sensitive signals observed in the present work.
