Search for dissertations about: "wall-bounded flows"

Showing result 1 - 5 of 39 swedish dissertations containing the words wall-bounded flows.

2. 1. Nonlinear dynamics in transitional wall-bounded flows

   Author : Miguel Beneitez Galan; Dan S. Henningson; Philipp Schlatter; Yohann Duguet; Tobias Schneider; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Mechanics; Teknisk mekanik;

   Abstract : This thesis focuses on numerical studies of subcritical transition to turbulence in shear flows. The thesis employs a framework based on nonlinear dynamics in the subsequent studies. The geometrical approach to subcritical transition pivots the concepts of edge manifold and edge state. READ MORE

4. 2. Application of Uncertainty Quantification Techniques to Studies of Wall-Bounded Turbulent Flows

   Author : Saleh Rezaeiravesh; Mattias Liefvendahl; Gunilla Kreiss; Pierre Sagaut; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Uncertainty Quantification; Large Eddy Simulation; Wall-Bounded Turbulent Flows; Wall Modeling; OpenFOAM; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Abstract : Wall-bounded turbulent flows occur in many engineering applications. The quantities of interest (QoIs) of these flows can be accurately obtained through experimental measurements and scale-resolving numerical approaches, such as large eddy simulation (LES). READ MORE

5. 3. Numerical studies of transtion in wall-bounded flows

   Author : Ori Levin; Dan Henningson; Nikolaus Adams; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layer; suction; wall jet; streaks; waves; periodic disturbance; localized disturbance; turbulent spot; algebraic growth; exponential growth; stability; transition thresholds; transition prediction; PSE; DNS; Fluid mechanics; Strömningsmekanik;

   Abstract : Disturbances introduced in wall-bounded flows can grow and lead to transition from laminar to turbulent flow. In order to reduce losses or enhance mixing in energy systems, a fundamental understanding of the flow stability and transition mechanism is important. READ MORE

6. 4. A new high-order method for direct numerical simulations of turbulent wall-bounded flows

   Author : Peter Lenaers; Arne Johansson; Hans Kuerten; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Incompressible wall-bounded flows; direct numerical simulations; high-order; compact finite differences; collocated grid; influence matrix method;

   Abstract : A new method to perform direct numerical simulations of wall-bounded flows has been developed and implemented. The method uses high-order compact finite differences in wall-normal (for channel flow) or radial direction (for pipe flow) on a collocated grid, which gives high-accuracy results without the effectfof filtering caused by frequent interpolation as required on a staggered grid. READ MORE

7. 5. Stability analysis and transition prediction of wall-bounded flows

   Author : Ori Levin; KTH; []
   Keywords : Boundary layer; wall jet; algebraic growth; exponential growth; lift-up effect; streamwise streaks; Tollmien-Schlichting waves; free-stream turbulence; roughness element; transition prediction; Parabolized Stability Equations; Direct Numerical S;

   Abstract : Disturbances introduced in wall-bounded .ows can grow andlead to transition from laminar to turbulent .ow. In order toreduce losses or enhance mixing in energy systems, afundamental understanding of the . READ MORE