Sökning: "streak instability"

Visar resultat 6 - 7 av 7 avhandlingar innehållade orden streak instability.

  1. 6. Linear and nonlinear development of perturbations in the asymptotic suction boundary layer

    Författare :Niklas Davidsson; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

    Sammanfattning : Turbulent processes play an important role in most flow systems. To optimize and control these flows, knowledge about the mechanisms that leads to and maintains turbulence is crucial. Boundary layers with wall suction are known to delay/prevent transition as well as separation. LÄS MER

  2. 7. Stability and transition on wind turbine blades

    Författare :Thales Coelho Leite Fava; Ardeshir Hanifi; Dan Henningson; Stefania Cherubini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Boundary layer stability; free-stream turbulence; laminar-turbulent transition; low-frequency oscillations; rotation effects; wind turbine blades.; Gränsskiktsstabilitet; friströmsturbulens; laminär-turbulent omslag; lågfrekventa svängningar; rotationseffekter; vindkraftverksblad.; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Transition on wind turbine blades is a highly complex phenomenon due to the myriad effects influencing the process. This thesis studies some of them, namely free-stream turbulence (FST), rotation, and three-dimensionality. The investigations employ large eddy simulations (LES) with and without (implicit or wall-resolved LES) a subgrid-scale model. LÄS MER