Thermite-for-demise (T4D): Experiments and numerical modelling on ball-bearing unit mock-ups containing thermite in an arc-heated wind tunnel

The use of thermite to aid spacecraft demise during atmospheric re-entry has been investigated in the ESA-TRP SPADEXO project. An experimental campaign in DLR's L2K arc-heated wind tunnel facility was dedicated to explore the Thermite-for-Demise concept. Steel mock-ups of a ball bearing unit, partially filled with thermite, were placed in L2K. The breadboards were then exposed to an air flux simulating the typical conditions that characterize spacecraft re-entry. In this paper, the key results of the tests are presented. The dispersion of a mechanically activated fraction of thermite proved to be effective in controlling the overall charge ignition temperature. Thermite-induced demise was experimentally verified in the wind tunnel. The SCARAB software was extended and used to rebuild the retrieved thermal data. The results of the simulations were in good agreement in both predicting the ignition timing and the effects of the thermite charge on the sample.