Hypersonic Transition Experiments in Ludwieg Tubes
Abstract
The project has accomplished a thorough analysis of measurements taken in two hypersonic Ludwieg tubes HLB in Braunschweig and HHK-6 at USAFA in Colorado. The analyses include modal decomposition of tunnel freestream measurements with pitot probes and hot wires, as well as assessment of boundary layer transition measurements on a 7 deg cone and on a blunt capsule model. The results indicate that there exist significantly different freestream disturbance levels in both facilities, particularly for elevated freestream temperatures. The elevated freestream disturbances in HHK-6 affect transition on slender models to a significant extent, as initial amplitudes of the hypersonic second instability modes are larger and break down to turbulence happens earlier. Much lesser differences between both tunnels were observed for boundary layer transition on blunted models with roughness-induced transition.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 10, 2018
- Accession Number
- AD1077645
Entities
People
- Rolf Radespiel