Effects of velocity slip and temperature jump are investigated for near continuum hypersonic flows. Specifically, flow over the hollow cylinder flare (HCF) geometry and expand-ing/compressing flow over the “Tick” geometry is simulated using both direct simulation Monte Carlo (DSMC) and computational fluid dynamics (CFD) methods. The CFD calculations are performed using both slip and no-slip models, while the DSMC method inherently models slip effects since it resolves molecular transport at the mean-free-path scale. Boundary layer profiles for the cylindrical portion of the HCF case, predicted by DSMC and CFD with slip, agree remarkably well, including the velocity slip and temperature jump values near the wall. The heat flux predictions between DSMC and CFD with slip are found to also agree closely, and both predictions remain below the heat flux measured experimentally. This indicates that slip flow may not be the reason for discrepancy between CFD results and the experimental heat flux measurements reported recently in the literature. More significant differences between DSMC and CFD are found near the leading edge of the Tick geometry. However, establishment of steady-state flow and precise grid convergence is not completely demonstrated for the DSMC solutions in this study, which may explain some of the discrepancy.
|Original language||English (US)|
|Title of host publication||AIAA Aerospace Sciences Meeting|
|Publisher||American Institute of Aeronautics and Astronautics Inc, AIAA|
|State||Published - 2018|
|Event||AIAA Aerospace Sciences Meeting, 2018 - Kissimmee, United States|
Duration: Jan 8 2018 → Jan 12 2018
|Name||AIAA Aerospace Sciences Meeting, 2018|
|Other||AIAA Aerospace Sciences Meeting, 2018|
|Period||1/8/18 → 1/12/18|
Bibliographical noteFunding Information:
This research was supported by NASA under grant number NNX14AQ75A, the Air Force Research Laboratory (AFRL) under grant number FA9453-17-1-0101 and the Air Force Office of Scientific Research (AFOSR) under grant number FA9550-17-1-0250.
© 2018 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.