Correlation of Recent and Historical Hemispherical Nose Tip Distributed Roughness Transition Data

摘要

An analysis of distributed roughness effects on boundary-layer transition for hemispherical nose tips has been conducted using archival data and new data generated through hypersonic wind-tunnel testing of hemisphere models with distributed roughness at Mach 6 and Mach 10. The historical data consist of a set of flight, wind-tunnel, and ballistic-range tests spanning more than 50 years of transition research. Flowfield solutions were generated for all new and archival test points to obtain boundary-layer transition parameters. The applicability of roughness-effect correlations developed for ballistic-range data and for wind-tunnel data was evaluated using these experimental data and the computed flowfield parameters. A new correlation was proposed that provides a better agreement between ballistic-range and wind-tunnel data than previous correlations.