Towards adaptive control of second mode instability in hypersonic boundary layer flow on a sharp circular base cone at zero angle of attack

Modal and nonmodal linear instability analysis of hypersonic boundary layer flow on a sharp cone is performed, at conditions aligning with those of recent experiments in the BAM6QT facility. A 3deg half-angle circular base cone is placed at zero angle of attack against oncoming Mach 6 flow at unit Reynolds numbers 1.1E7 1/m < Re_1 < 1.2E7 1/m. Taylor-Macoll theory is used to compute post-shock conditions and provide edge conditions for the calculation of similar compressible boundary layer profiles. The temporal compressible axisymmetric linear stability eigenvalue problem is solved and N-factor computations reveal maximally amplified frequencies that fall well within one standard deviation of the experimental results. Subsequently, the initial value problem is solved and the short-time algebraic growth of perturbations is documented. Presently, development of a novel adaptive flow control strategy for modal and nonmodal boundary layer disturbances is underway, aiming at full coupling of reduced order model wall-dynamics and classic linear stability equations. Finally, a framework that incorporates the effect of surface motion, both prescribed and coupled to the flow dynamics via compliant metamaterials, on the resulting stability properties will be presented along with preliminary results.