Experimental Investigations Addressing Steam Release in the Water Pool Through a Multi-Hole Sparger and Spray Water Activation in the Gas Space

Abstract

This paper presents the experimental results and the phenomenological analyses of the H2P4 tests performed in the PANDA facility, within the OECD/NEA HYMERES project. H2P4 series is characterized by two phases: (i) the steam injection in the water pool with development of thermally stratified layer and pressurization of the system, and (ii) the water spray injection in the gas space above the pool to depressurize the system. The sparger submergence was changed between H2P4_2 and H2P4_3 tests. The results indicate that the sparger submergence affects the pool's thermal behavior, and the pressurization history. When the submersion height is decreased, the vessel's pressurization occurs more quickly. An analysis of the experimental data is carried out using mass and energy balance for the liquid and gas volumes. This analysis contributes to the understanding of the pool phenomena and suggests that mass and energy are lost through vaporization at the liquid-gas interface and a significant amount of steam is condensed at the walls.

Keywords: PANDA, HYMERES project, vapor injection, spray