Interaction of a Helium/Air Stratified Layer with an Air Jet Coming from Below: Large and Small Scale Experiments and Scaling Analysis

Abstract

In the frame of the OECD-NEA/SETH-2 project, an experimental programme has been carried out in the PANDA facility at PSI and in the MISTRA facility at CEA until December 2010. Part of the program focuses on gas stratification break-up induced by mass sources and similar tests have been performed in both facilities. The present paper gives an overview of the CEA experimental results dedicated to the study the phenomena of erosion by a low momentum air jet on the helium/air stratified layer located at the top of the confined volume. The tests were conducted in the MISTRA, a large facility. Different mass flow rates of air were used, inducing different regimes including pure diffusive mixing, global dilution and slow erosion processes, characterized by the interaction Froude number. A discussion ended this paper with some comparison of the results with CAST3M CFD simulations.