Innovative calibration methodology for gardon gauge heat flux meter

For a space mission the re-entry into earth atmosphere is a crucial phase, because of the severe aerothermodynamic conditions. This has always represented a problem of great interest, as it is fundamental to study the behavior of the structures of the spacecraft invested by the atmosphere where very high temperatures are generated. The necessity of testing the models in similar conditions to re-entry phase pushed towards the realization of specific on-ground facilities. In these laboratories one of the main purposes is to reproduce very high heat fluxes onto the models, representative of what happens during the re-entry mission phase. In this scenario, the Plasma Wind Tunnel "SCIROCCO""of the Italian Aerospace Research Center (C.I.R.A. S.C.p.A) in Capua represents the largest and most powerful hypersonic facility in the world. Here it is possible to test models with heat fluxes up to 3000 kW/m. The measure of the heat fluxes in the test facility are performed with Gardon Gauge transducers. Despite the fundamental importance of these sensors, there is currently no possibility to calibrate them for the aforementioned heat flux values. In this work an innovative calibration methodology is proposed, using a pulsed LASER beam which allows to obtain high and repeatable heat flux with low power consumption. The results show the feasibility of the proposed methodology.