TY - GEN
T1 - Optimal disturbances in the supersonic boundary layer past a sharp cone
AU - Zuccher, Simone
AU - Shalaev, Ivan
AU - Tumin, Anatoli
AU - Reshotko, Eli
PY - 2006
Y1 - 2006
N2 - Optimal disturbances for the supersonic flow past a sharp cone are computed in order to assess the effects due to flow divergence. This geometry is chosen because previously published studies on compressible optimal perturbations for flat plate and sphere did not allow to discriminate the influence of divergence alone, as many factors characterized the growth of disturbances on the sphere (flow divergence, centrifugal forces and dependence of the edge parameters on the local Mach number). Flow-divergence effects result in the presence of an optimal distance from the cone tip for which the optimal gain is the largest possible, showing that divergence effects are stronger in the proximity of the cone tip. By properly rescaling the gain, wavenumber and streamwise coordinate due to the fact that the boundary layer on the sharp cone is √3 thinner than the one over the flat plate, it is found that both the gain and the wavenumber compare fairly well. Moreover, results for the sharp cone collapse into those for the flat plate when the initial location for the computation tends to the final one and when the azimuthal wavenumber is very large. Results show also that a cold wall enhances transient growth.
AB - Optimal disturbances for the supersonic flow past a sharp cone are computed in order to assess the effects due to flow divergence. This geometry is chosen because previously published studies on compressible optimal perturbations for flat plate and sphere did not allow to discriminate the influence of divergence alone, as many factors characterized the growth of disturbances on the sphere (flow divergence, centrifugal forces and dependence of the edge parameters on the local Mach number). Flow-divergence effects result in the presence of an optimal distance from the cone tip for which the optimal gain is the largest possible, showing that divergence effects are stronger in the proximity of the cone tip. By properly rescaling the gain, wavenumber and streamwise coordinate due to the fact that the boundary layer on the sharp cone is √3 thinner than the one over the flat plate, it is found that both the gain and the wavenumber compare fairly well. Moreover, results for the sharp cone collapse into those for the flat plate when the initial location for the computation tends to the final one and when the azimuthal wavenumber is very large. Results show also that a cold wall enhances transient growth.
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U2 - 10.2514/6.2006-1113
DO - 10.2514/6.2006-1113
M3 - Conference contribution
AN - SCOPUS:34250860736
SN - 1563478072
SN - 9781563478079
T3 - Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting
SP - 13478
EP - 13493
BT - Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting
PB - American Institute of Aeronautics and Astronautics Inc.
T2 - 44th AIAA Aerospace Sciences Meeting 2006
Y2 - 9 January 2006 through 12 January 2006
ER -