The investigation of the spatial and temporal homogeneity of the air plasma flow produced by the SCIROCCO arc-jet facility was carried out by applying both intrusive and non-intrusive techniques. The static pressure was measured through four pressure taps equally spaced on the exit section of the nozzle. The stagnation pressure and the heat flux radial profiles were measured using a water cooled probe. Finally, a High-Speed Camera (HSC) and a Photomultiplier Tube (PMT) were used to perform the time-resolved analysis of the spontaneous radiation of the free-stream plasma flow. HSC movies were acquired at 1.1 kHz and the extracted frames were elaborated using both time and spectral domain analysis procedures: the mean radiation and the variance distributions were computed using the entire set of frames composing the movies. The PMT signal (100 kHz bandwidth) was acquired 44 cm away from the exit section of the nozzle (0.4 diameters) and the FFT was performed. For the present work, the plasma was investigated at two nominal operating conditions: arc current I=2000 A, air mass flow rate ?_(air)=0.7 kg/s and I=4000 A, ?_(air)=1.3 kg/s. The coupling of the results coming from the different techniques showed that the plasma flow produced by SCIROCCO, for the two operating conditions of interest, can be considered spatially and temporarily homogeneous.
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