AbstractApplicability of experimental results to a full-size system depends on the scaling criteria on which the test article/fluid medium is used. This paper presents a careful review and assessment of a number of key parameters which influence fluid stability phenomena relevant to the IFE wall protection schemes, and provides guidance for future simulation experiments. The analysis shows that the non-dimensional jet surface ripple size can be reproduced by simultaneously preserving prototypical jet Reynolds and Weber numbers. The results show the difficulties of using water as a simulant for liquid protectants in experiments for evaluating IFE thin and thick liquid wall protection schemes. The analysis also shows that a modified HTS salt seems a good simulant for Flibe and that liquid sodium a good simulant for liquid lead. However, in the absence of information on liquids other than water, serious questions remain concerning the issue of scaling. Nevertheless, to best utilizing the available R&D resources, further experiments should be performed using fluids with significantly lower vapor pressures, such as liquid metals or low-melting temperature salts or eutectics.