GROWTH AND CONTROL OF NONLINEAR GORTLER VORTICES IN HYPERSONIC BOUNDARY LAYERS OVER CONCAVE SURFACES
Abstract
The transition of an hypersonic boundary layer has a major influence on the aerodynamic performance of flight vehicles and is a topic of wide interest in the design of high-speed wind tunnels because of its evolution on the nozzle. It is absolutely crucial to maintain the boundary layer over the nozzle in the laminar state because otherwise acoustic radiation from turbulent boundary layers may irreparably disturb the free stream flow and ruin the measurements in the core of the wind tunnel. Because of the design specifications of the nozzle, its surface is diverging and concave, which causes inviscid centrifugal instabilities in the boundary layer, leading to the formation of fast-growing Gortler vortices and transition to turbulence. The control of these disturbances along the nozzle walls has therefore been actively researched to achieve the design of low-disturbance (quiet) wind tunnels, where the measurements can faithfully reproduce the instability and transition regimes during high-altitude flight.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2023
- Source ID
- FA86552117008
Entities
People
- Pierre Riccó
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Sheffield