Search for dissertations about: "Symmetry and equations"

Showing result 6 - 10 of 54 swedish dissertations containing the words Symmetry and equations.

2. 6. Numerical study on instability and interaction of wind turbine wakes

   Author : Sasan Sarmast; Dan. S. Henningson; Per-Åge Krogstad; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind turbine wakes; Stability; interaction; POD; DMD; Teknisk mekanik; Engineering Mechanics;

   Abstract : Numerical simulations of the Navier-Stokes equations are conducted to achieve a better understanding of the behavior of wakes generated by the wind turbines. The simulations are performed by combining the in-house developed code EllipSys3D with the actuator line technique. READ MORE

4. 7. Nature-inspired passive flow control using various coatings and appendages

   Author : Ugis Lacis; Shervin Bagheri; Christophe Eloy; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flow control; passive appendage; surface coating; pressure drag; friction drag; Flödeskontroll; passiva bihang; ytbeläggning; tryckmotstånd; friktionsmotstånd;

   Abstract : There is a wide variety of tails, fins, scales, riblets and surface coatings, which are used by motile animals in nature. Since organisms currently living on earth have gone through millions of years of evolution, one can expect that their design is optimal for their tasks, including locomotion. READ MORE

5. 8. Numerical study on instability and interaction of wind turbine wakes

   Author : Sasan Sarmast; Dan S. Henningson; Per-Åge Krogstad; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind Turbines; CFD; EllipSys3D; Actuator Line; Stability; Wake; Vortex Model; SRA - E-Science SeRC ; SRA - E-vetenskap SeRC ;

   Abstract : The optimization of new generation of the wind farms is dependent on our understanding of wind turbine wake development, wake dynamics and the interaction of the wakes. The overall goal of the optimization is decreasing the fatigue loading and increasing the power production of the wind farms. READ MORE

6. 9. Wind-turbine wakes - Effects of yaw, shear and turbine interaction

   Author : Elektra Kleusberg; Dan Henningson; Philipp Schlatter; Stefan Ivanell; Johan Meyers; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind-turbine wakes; yaw; tip-vortex breakdown; shear; computational fluid dynamics; actuator-line method; spectral-element method; Vindturbinsvakar; girning; turbulent nedbrott hos spetsvirvlar; skjuvning; vakinteraktion; beräkningsströmningsdynamik; actuator line-metod; spektralelementmetod; Engineering Mechanics; Teknisk mekanik;

   Abstract : The actuator-line method is used together with the incompressible Navier–Stokes equations to investigate the flow development behind wind turbines. Initial investigations focus on providing a thorough validation of the implementation in the spectral-element flow solver Nek5000 against existing numerical and experimental datasets. READ MORE

7. 10. Compact Relativistic Matter Shells with Massless and Charged Particles

   Author : Maximilian Thaller; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Spherical Symmetry; massless Einstein-Vlasov system; Einstein-Vlasov-Maxwell system; Static Solutions; Vlasov matter; General Relativity; Einstein-Vlasov-Maxwell system;

   Abstract : The Vlasov model is a matter model that is widely used in physics. In the context of astrophysics and cosmology it describes an ensemble of self gravitating, collisionless particles. These particles can be interpreted as for example ions, stars, or galaxies. READ MORE