AEROTHERMAL ANALYSIS OF THE ATMOSPHERIC REENTRY OF THE INTERMEDIATE EXPERIMENTAL VEHICLE (IXV)
The Intermediate eXperimental Vehicle (IXV) is the first European attempt at a full atmospheric reentry from low Earth orbit conditions using an automatic lifting body. The present study is an aerothermal analysis of the IXV nose. This part is thermally protected on the outer surface by a panel of ceramic matrix composite C/SiC and several insulation layers. Temperature measurements were carried out during the flight by thermocouples installed between the C/SiC panels and the insulation layers. In this respect, a numerical method is performed to estimate the heat transfer conditions at the external surface thanks to the temperature measurements. This
inverse nonlinear transient heat conduction problem is solved thanks to the least-squares criterion and Beck's method of regularization based on future time steps. The results are compared to the predictions obtained during the pre-flight phase. As expected, the heat flux was overestimated during the pre-flight phase due to the assumptions on the C/SiC catalytic behavior. Finally, a sensitivity analysis is applied and allows to notice that the calibration of thermocouples, and the thickness and the emissivity of the C/SiC have the largest
impact on the accuracy of the estimated heat flux. Since the flight materials properties never correspond to the
theoretical ones, this study also allows to estimate an interval of the possible heat flux due to the uncertainties
of the parameters and the calibration of the thermocouples.
, Thermal insulation