Full-Scale BOLT-1B Experiments at Flight Matched Conditions in X3/R

A full scale model of the BOLT-1B flight experiment geometry was tested in The University of Queensland's X3/R hypersonic facility. Existing and new flow conditions for X3/R using the Mach 7b nozzle were used and developed to provide flight-equivalent flows at ten points the descent trajectory of the BOLT-1B flight at altitudes between 24 and 33 km. The freestream unit Reynolds numbers ranged between 1.69 and 6.20 million/m. Test times varied from 3 to 7 ms. Heat flux measurements were captured at vehicle-matched locations on the primary experimental surface using thin-film heat transfer gauges. Laminar, transitional and turbulent boundary layers were observed evolving over the increasing Reynolds number freestream conditions. Results show the centre-line transition front moving upstream, as well as the establishment and advancement of the outboard wedge-shaped turbulent structures.