Simulation of Break-up of Gas Stratification by a Vertical Jet using the GOTHIC Code
The assessment of the capability of three-dimensional computational tools to predict erosion and break-up of stratified conditions that may build-up in the containment during an earlier phase of a hypothetical severe accident with release of hydrogen is the object of worldwide intense research. In conjunction with the OECD SETH-2 project the GOTHIC code is assessed against experiments where the mixing is caused by sources or sinks of mass and/or heat. This paper reports on simulation results of selected experiments where the initial helium stratification in a vessel is destroyed by a vertical jet originating from an injection below the initial density interface. A 3-D coarse mesh as well as various finer 2-D meshes was used to simulate the evolution of the helium distribution generated by jets having different initial momentum. In general, the 3-D calculations predict too slow mixing in the vessel and a reasonable agreement between calculated and measured gas concentrations can only be achieved with a sufficiently fine mesh. These results can be explained by comparing the calculated velocity field with that measured with PIV technique, which also provides valuable insight into the mechanisms of the interaction between the jet and the density interface.
Containment stratification break-up buoyant jets GOTHIC code assessment.
Michele Andreani Ralf Kapulla Robert Zboray
Paul Scherrer Institut (PSI) CH-5232 Villigen PSI, Switzerland
国际会议
上海
英文
2335-2346
2010-10-10（万方平台首次上网日期，不代表论文的发表时间）