The energy transfer mechanisms for Mack’s second mode and a supersonic mode based on spatial linear stability theory for a Mach 6 flat plate flow with Tw = 0.5T∞ is investigated. For the current conditions, the supersonic mode is unstable but obtains a relatively low amplification rate in comparison to the second mode. The energy analysis conducted in this paper shows that the total energy of the second mode is available throughout the boundary layer, however, for the supersonic mode, it is concentrated closer to the wall. The combined effect of thermal production and production density dissipates most of the energy away from the critical layer for the supersonic mode. As opposed to the second mode, a significant amount of energy is available in the free-stream in the case of supersonic mode. It is found that the energy is provided from the pressure strain transport term counteracting the shear-work. In the second part of the paper, direct numerical simulations were performed for the same flow conditions, and a decomposition of the disturbance flow field was performed. Some differences in the growth rates especially in the region where the supersonic mode appears was observed. Although the flow decomposition showed that the unstable mode F dominates the disturbance flow field, there appears to be a non-negligible contribution from the stable supersonic mode.
|Title of host publication||AIAA Scitech 2021 Forum|
|Number of pages||26|
|State||Published - 2021|
|Event||AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2021 - Virtual, Online|
Duration: Jan 11 2021 → Jan 15 2021
|Name||AIAA Scitech 2021 Forum|
|Conference||AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2021|
|Period||1/11/21 → 1/15/21|
Bibliographical noteFunding Information:
We gratefully acknowledge Prof. Tumin for providing his linear stability solvers and his support for these tools. The authors would like to recognize and show appreciation for the financial support provided by NASA Kentucky EPSCoR RA Award no. 80NSSC19M0144 with E. Stern as the technical monitor and NASA EPSCoR R3 Award no. 80NSSC19M0084 with M. Barnhardt as the technical monitor. The authors would also like to thank the collaborators from NASA Ames Research Center, NASA Langley Research Center, and the NASA Johnson Space Center.
© 2021, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.
ASJC Scopus subject areas
- Aerospace Engineering