Oblique-mode breakdown in hypersonic and high-enthalpy boundary layers over a blunt cone

Abstract The nonlinear analyses of the hypersonic and high-enthalpy boundary-layer transition had received little attention compared with widely-studied linear instabilities. In this work, oblique-mode breakdown, as one most available mechanisms, is studied using parabolized stability equations (NPSE) consideration thermal-chemical non-equilibrium effects. flow over a blunt cone computed at free-stream Mach-number 15. rope-like structures spontaneous radiation sound waves are observed in schlieren-like picture. It also illustrated that disturbances species mass vibrational temperature near wall mainly generated by product term wall-normal velocity disturbance mean-flow gradient. comparison to CPG flow, TCNE effects destabilize second mode push upstream N factor envelope. higher growth rate oblique wave leads stronger streamwise vortices harmonic waves.