Abstract
The purpose of this study is to apply existing theories of linear temporal instability and critical-state concept on realistic delta wing flows. Three-dimensional laser Doppler velocimetry measurements are performed on two delta wings with different geometries in transverse planes both upstream and downstream of the vortex breakdown. Representative models of the velocity fields in the leading-edge vortices are deduced from these measurements and allow us to examine the stability properties of such flows. As expected, helical modes are destabilized downstream of the breakdown with characteristics that agree with generalized centrifugal instability theory for large azimuthal wave numbers. Upstream of the breakdown, the perturbations are stabilized or weakly amplified. Moreover, a simple criticality criterion is shown to efficiently describe the conditions of breakdown in our experiments. These results suggest that inviscid and linear stability analysis based on the mean velocity field is sufficient to account for the linear stability behavior of delta wing flows at high Reynolds numbers.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
