Pressure Gradient Effects on Transition Location over Axisymmetric Bodies at Incidence in Supersonic Flow: Progress Report of JAXA-NASA Joint Research Project on Supersonic Boundary Layer Transition Part 2

Boundary layer transition along the leeward symmetry plane of axisymmetric bodies at nonzero angle of incidence in supersonic flow was investigated numerically as part of joint research between the Japan Aerospace Exploration Agency (JAXA) and the National Aeronautics and Space Administration (NASA). Stability of the boundary layer over five axisymmetric bodies (namely, the Sears-Haack body, the semi-Sears-Haack body, two straight cones and the flared cone) was analyzed in order to investigate the effects of axial pressure gradients, freestream Mach number and angle of incidence on the boundary layer transition. Moreover, the transition location over four bodies was detected experimentally. The strong effects of axial pressure gradients on the boundary layer profiles along the leeward ray, including an earlier transition under adverse axial pressure gradients, were indicated in both numerical predictions and experimental measurements. The destabilizing effect of the pressure gradient on the boundary layer flow within the leeward symmetry plane is shown to be related to the three-dimensional dynamics involving an increasing build-up of secondary flow along the leeward symmetry plane under an adverse axial pressure gradient. A detailed description of the mean flow computation, which forms the basis for the present linear stability analysis, is provided in an accompanying report that forms part 1 of this document.
形態: カラー図版あり
Physical characteristics: Original contains color illustrations
資料番号: AA1730005000
レポート番号: JAXA-RR-17-003E