Characterisation Measurements for a Ludwieg Tube

Abstract

This work aims to evaluate and characterize the performance and operational boundaries of the Hyperschall Prüfstand Göttingen (HPG), a hypersonic Ludwieg tube at the DLR Institute of Aerodynamics and Flow Technology Göttingen. The HPG simulates hypersonic freestream conditions, ranging from Mach 6 to Mach 10, providing a controlled environment for experimental hypersonic and advancing the understanding of hypersonic gas dynamics. This study focuses on assessing the storage tank's pressure and temperature limits to determine the corresponding boundaries within the test section, thus understanding the impact of these constraints on the complete operational envelope. Additionally, boundary layer effects in supersonic freestream are explored and the feasibility of optical measurement methods on the HPG is examined. This work also discusses improvements and progress made on the HPG during its commissioning such as extending steady test time, pitot pressure rake design, diffuser design, and further improvements that could be made to extend the application range of the HPG.