Nonlinearly most dangerous disturbance for high-speed boundary-layer transition

  title={Nonlinearly most dangerous disturbance for high-speed boundary-layer transition},
  author={Reza Jahanbakhshi and Tamer A. Zaki},
  journal={Journal of Fluid Mechanics},
  pages={87 - 121}
Laminar-to-turbulent transition in a zero-pressure-gradient boundary layer at Mach 4.5 is studied using direct numerical simulations. For a given level of total disturbance energy, the inflow spectrum was designed to correspond to the nonlinearly most dangerous condition that leads to the earliest possible transition Reynolds number. The synthesis of the inlet disturbance is formulated as a constrained optimization, where the control vector is comprised of the amplitudes and relative phases of… 
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