Characteristics of Spatiotemporally Homogenized Boundary Layers at Atmospheric Reentry-like Conditions*

Turbulent boundary layers approximating those found on the NASA Orion Multi-Purpose Crew Vehicle thermal protection system during atmospheric reentry from the International Space Station have been studied by direct numerical simulation using a ``slow growth'' spatiotemporal homogenization approach recently developed by Topalian et al. The two data sets generated were $\mbox{Ma}_{e}\approx{}0.9$ and $1.15$ homogenized boundary layers possessing $\mbox{Re}_{\theta}\approx{}382$ and $531$, respectively. Edge-to-wall temperature ratios were approximately 4.15 and wall blowing velocities, $v_w^{+} = v_w / u_\tau$, were roughly $8\times10^{-3}$. The favorable pressure gradients had Pohlhausen parameters between 25 and 42. Nusselt numbers under 22 were observed. Small or negative displacement effects are evident. Near-wall vorticity fluctuations show qualitatively different profiles than observed by Spalart [J. Fluid Mech. 187 (1988)] or Guarini et al. [J. Fluid Mech. 414 (2000)] suggesting that the simulations have atypical structures perhaps as a consequence of wall blowing or the homogenization.