Identification of Bypass Transition Onset Markers Using Direct Numerical Simulation

Efficacy of several large-scale flow parameters as transition onset markers are evaluated using direct numerical simulation (DNS) of boundary layer bypass transition. Preliminary results identify parameters (k(2D)/v) and u'/U-infinity to be a potentially reliable transition onset marker, and their critical values show less than 15% variation in the range of Re and turbulence intensity (TI). These parameters can be implemented into general-purpose physics-based Reynolds-averaged Navier-Stokes (RANS) models for engineering applications.