Search for dissertations about: "flat plate"

Showing result 6 - 10 of 72 swedish dissertations containing the words flat plate.

2. 6. Measurements and Prediction of Friction Drag of Rough Surfaces

   Author : Bercelay Niebles Atencio; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PIV; RANS; Turbulent Boundary Layers; Flat Plate; Resolved CFD; Hydrodynamics; Roughness Function; Wall Functions; Rotating Disk;

   Abstract : Owing to the increased sea transportation of goods, the environmental impacts of this activity are becoming more and more important, since a ship experiences resistance that directly affects its performance and fuel consumption. The growth of marine organisms (fouling) on ship hulls increases the roughness of the hull surface, which in turn causes a rise in ship resistance with a consequent increase in fuel consumption and greenhouse emissions of up to 40%. READ MORE

4. 7. Flow control and reduced-order modelling of transition in shear flows

   Author : Reza Dadfar; Dan Henningson; Vasssilis Theofilis; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow control; plasma actuator; wing; leading edge; flat plate; wind turbine; optimal controller; model reduction; proper orthogonal decomposition; dynamic mode decomposition.;

   Abstract : In this thesis direct numerical simulation is used to investigate the possibility to delay the transition from a laminar to a turbulent flow in boundary layer flows. Furthermore, modal analysis techniques are used to identify the coherent structures in wind turbine wake. READ MORE

5. 8. Receptivity of Boundary-Layer Flows over Flat and Curved Walls

   Author : Lars-Uve Schrader; Luca Brandt; Dan Stefan Henningson; Gregoire Casalis; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Boundary-layer receptivity; laminar-turbulent transition; swept-plate boundary layer; Görtler flow; leading-edge effects; swept-wing flow; crossflow vortices; Görtler rolls; disturbance streaks; wall roughness; free-stream turbulence; Fluid mechanics; Strömningsmekanik;

   Abstract : Direct numerical simulations of the receptivity and instability of boundary layers on flat and curved surfaces are herein reported. Various flow models are considered with the aim to capture aspects of flows over straight and swept wings such as wall curvature, pressure variations, leading-edge effects, streamline curvature and crossflow. READ MORE

6. 9. Study of adverse-pressure-gradient effects on a flat-plate boundary layer at high Reynolds numbers

   Author : Ramón Pozuelo; Ricardo Vinuesa; Philipp Schlatter; Ivette Rodriguez; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; simulations; turbulent boundary layers; adverse pressure gradients.; Teknisk mekanik; Engineering Mechanics;

   Abstract : Turbulent boundary layers are present in many aspects of life, from the weather and wind currents to transportation, production of energy or mixing processes. Understanding turbulent motions can allow for an improvement and development of technical devices, techniques or diagnosis of phenomena where a fluid flow is in the turbulent regime. READ MORE

7. 10. Analysis and control of transitional shear flows using global modes

   Author : Shervin Bagheri; Dan Henningson; Alessandro Bottaro; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; flow control; hydrodynamic stability; global modes; jet in crossflow; flat-plate boundary layer; laminar-turbulent transition; Arnoldi method; Koopman modes; balanced truncation; direct numerical simulations.; Fluid mechanics; Strömningsmekanik;

   Abstract : In this thesis direct numerical simulations are used to investigate two phenomenain shear flows: laminar-turbulent transition over a flat plate and periodicvortex shedding induced by a jet in cross flow. The emphasis is on understanding and controlling the flow dynamics using tools from dynamical systems and control theory. READ MORE