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Arc-jet facilities have been the norm for ablation experiments used to calibrate computational models to date. However, the arc jet has a few major limitations and challenges, including non-uniform enthalpy distribution, non-equilibrium state, change of surface quality during testing and the extent of oxidation, to name but a few. A novel plasma technique for preheating axisymmetric heatshield samples in hypersonic impulse facilities is presented herein. The major aim of this innovative work is to help reduce the large variations of ablation rate predictions, space vehicle materials and missile design/testing, obtain strongly coupled hypersonic boundary layers and achieve lower cost of aerothermodynamics experiments. This present work remains one of the most highly anticipated solutions to maximise payload success and replicate high surface temperatures identical to those experienced by real flight vehicles. This work makes a useful contribution to re-entry studies under conditions that replicate the characteristics of re-entry flights. Future applications for the technique are expected to be found in hypersonic impulse facilities that can simulate the true flow energy under re-entry conditions.

Measurements of mass ablation rates in hypersonic flows are used to calibrate computational models. A novel plasma technique for preheating axisymmetric samples of heatshield materials has been developed and applied to ablation of graphite sample through this work. The experimental probe was very similar to the European standard probe, normal to the flow. The Scanning Electron Microscope (SEM) was used to examine the surface characteristics; and the experiments show a significant spatial variation in thickness loss for the graphite test material over the disc radius though the spatial variation was still largely axisymmetric. The present work does support reasonable contributions to reentries and can further be developed to validate computational models under conditions that replicate characteristics of reentry flights.