Hot Wall Testing Methodology for Impulse Facilities

The design of hypersonic flight systems requires extensive ground testing to understand the flow characteristics that are important for the flight vehicle. The work presented within this paper demonstrates a new model pre-heating technique that allows models to be tested in hypersonic impulse facilities with wall temperatures in excess of 2000 K. Utilising carbon fibre models and resistive heating, this technique enables a new range of testing opportunities in these facilities. Preliminary testing has been conducted demonstrating increased surface chemistry rates with an elevated wall temperature model representative of a blunt body atmospheric entry vehicle. This methodology has enabled a range of new testing to be proposed including blunt body models investigating the effect of hot walls, ablating surfaces and surface reactions on the flow field. Additional testing targeting boundary layer physics and scramjet flow phenomena have also been proposed including investigations into transition, boundary layer development, shock interactions, boundary layer combustion, mixing and ignition lengths and radical farming. The effect of the increased wall temperature on these phenomena is of great interest for the understanding of the hypersonic flow fields.