Experimental Ablation Measurements in Hypersonic Flows using Novel Preheating Technology
Measurements of mass ablation rates in hypersonic flows are used to calibrate computational models, and the arc jets have been the norm for ablation experiments. However, the quality of experimental data from arc jet facilities are limited by non-uniform enthalpy distribution, non-equilibrium state, change of surface quality during testing, and the extent of oxidation. This publication presents an innovative research work, leading to a new era of scientific breakthrough in aerothermodynamics experiments and hypersonic re-entry studies using new preheating technology. The impetus for this new technology is to help reduce the large variations in ablation rate predictions around the world. A graphite disc of 50 mm diameter and 2 mm thickness was heated from the downstream side with a plasma to approximately 2500 K, and then exposed to a cold Mach 4.5 flow using the Ludwieg tube facility at the University of Southern Queensland (TUSQ) in the atmospheric blowdown configuration. The experimental probe was very similar to the European standard probe, and presented herein are the results from material loss and surface recession for the experiments. The next generation experimental model (NGEM), which has been specifically designed for the next generation of researchers is also presented, to be used in validating computational models in excess of 3000K surface temperatures under conditions that replicate characteristics of re-entry flights.
