US 11,981,421 B2
Flow control techniques for delaying or accelerating laminar-turbulent boundary-layer transition for high-speed flight vehicles
Hermann F. Fasel, Tucson, AZ (US); and Christoph Hader, Tucson, AZ (US)
Assigned to Arizona Board of Regents on behalf of the University of Arizona, Tucson, AZ (US)
Filed by ARIZONA BOARD OF REGENTS ON BEHALF OF THE UNIVERSITY OF ARIZONA, Tucson, AZ (US)
Filed on Dec. 24, 2020, as Appl. No. 17/134,047.
Claims priority of provisional application 62/953,367, filed on Dec. 24, 2019.
Prior Publication US 2021/0316844 A1, Oct. 14, 2021
Int. Cl. B64C 21/04 (2023.01); B64C 21/06 (2023.01); B64C 23/00 (2006.01); B64C 30/00 (2006.01)
CPC B64C 23/005 (2013.01) [B64C 21/04 (2013.01); B64C 21/06 (2013.01); B64C 30/00 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method of controlling boundary-layer transition for a hypersonic vehicle, the method comprising:
determining a location of onset of boundary-layer transition that naturally develops during hypersonic flight of the hypersonic vehicle; and
providing a pair of flow control strips imbedded in a surface or wall or skin of the hypersonic vehicle such that the boundary-layer transition is delayed or prevented during hypersonic flight of the hypersonic vehicle, the pair of flow control strips comprising an upstream strip and a downstream strip, and the upstream strip and the downstream strip are immediately adjacent and share a common divider,
wherein the delayed or prevented locations of the transition result in a change in the hypersonic boundary layer during the hypersonic flight of the hypersonic vehicle, and
wherein the change in the hypersonic boundary layer transition affects skin friction drag, aero-thermodynamic heating, and pressure fluctuations in the boundary layer of the hypersonic vehicle.