Technical Report Pressure Gradient Effects on Mean Flow over Axisymmetric Bodies at Incidence in Supersonic Flow: Progress Report of JAXA-NASA Joint Research Project on Supersonic Boundary Layer Transition Part 1

Ishikawa, Hiroaki  ,  Tokugawa, Naoko  ,  Li, Fei  ,  Choudhari, Meelan  ,  White, Jeffery  ,  石川, 敬掲  ,  徳川, 直子  ,  Li, Fei  ,  Choudhari, Meelan  ,  White, Jeffery

JAXA-RR-17-002Epp.1 - 40 , 2017-09-15 , Japan Aerospace Exploration Agency (JAXA) , 宇宙航空研究開発機構(JAXA)
Boundary layer transition along the leeward symmetry plane of axisymmetric bodies at zero and non-zero angles of incidence in supersonic flow was investigated numerically as part of joint research between the Japan Aerospace Exploration Agency (JAXA) and National Aeronautics and Space Administration (NASA). Mean flow over five axisymmetric bodies (namely, a Sears-Haack body, a semi-Sears-Haack body, two straight cones and a flared cone) was analyzed to investigate the effects of axial pressure gradient, freestream Mach number, and angle of incidence on boundary layer transition. Computations revealed the strong effects of axial pressure gradient on boundary layer profile in the vicinity of the leeward symmetry plane, highlighting the three-dimensional dynamics associated with increasing build-up of secondary flow under an adverse axial pressure gradient. Independent flow solutions obtained using different flow solvers and different grids at JAXA and NASA, respectively, were in good agreement with each other. Slight differences between the two sets of solutions are attributed to a combined effect of the differences between respective thermal wall boundary conditions, numerical grids, and flow solvers. The difference due to the thermal boundary condition is confirmed to be physical and was observed for all flow conditions, as expected. However, the other differences were rather minor, and were noticeable only for the straight cone and flared cone configurations. The conditions under which these minor differences are observed and the magnitudes of these differences remain an open question. Despite being coarser than the NASA grids, the JAXA grids are shown to be sufficient for providing basic state definition for the linear stability analysis. Specifically, the results demonstrate that appropriate grid spacing had been used to obtain accurate boundary layer profiles. The present report represents part 1 of a two-part document based on the joint computational effort. Part 1 is devoted to the results of mean flow computations and the results of linear stability analyses and the corresponding experiments are described in part 2.
Physical characteristics: Original contains color illustrations
形態: カラー図版あり

Number of accesses :  

Other information