Experiments were executed to investigate the effect of ablative outgassing on boundary-layer instabilities on a slender cone in Mach 6 quiet flow. A 5 ° half-angle cone with solid and porous nose tips was tested. The porous nose tips were of varying bluntness: nominally sharp, R N = 1.60    mm , and R N = 3.18    mm . The permeability of each nose tip was measured using a modified ISO standard, and the outflow was measured using miniature hot-wire anemometry. The model was instrumented with surface pressure transducers and an atomic layer thermopile, and high-speed schlieren was used to visualize the boundary layer. Experiments were done in the Boeing/AFOSR Mach 6 Quiet Tunnel at Purdue University at approximate Reynolds numbers of 7.5 × 10 6 / m and 15 × 10 6 / m and with varying blowing rates. Without blowing, bluntness suppressed the second-mode instability. In all cases, blowing advanced transition upstream. On the sharp cone and the R N = 1.60    mm geometry, second-mode instabilities were the dominant transition mechanism. With the R N = 3.18    mm nose tip installed, second-mode waves were not observed. However, blowing advanced transition, and a 40 kHz instability dominated laminar-to-turbulent transition on the R N = 3.18    mm geometry.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Boundary-Layer Instabilities on Variable Bluntness Cones with Outgassing in Hypersonic Quiet Flow


    Contributors:

    Published in:

    AIAA Journal ; 63 , 6 ; 2105-2121


    Publication date :

    2025-06-01




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English