New Panda instrumentation for assessing gas concentration distributions in containment compartments

The increased use of CFD for analysis and design purposes demands high quality data to validate the code's results. The present paper introduces a measuring system able to characterize the gas composition and to withstand the rough conditions inside a large-scale containment test facility. The speed of sound in ideal gases is a function of the gas composition. Out of the measured time of flight of an ultra sound pulse between a pair of transducers the integral speed of sound along the chord spanned between the transducers is computed. This quantity characterizes the gas composition and therefore can be used for model validation purposes even though concentrations of individual components cannot be resolved in cases of more than a binary mixture. The results of preliminary tests specifying the measurement system's properties are discussed. (authors)