Sökning: "Rotation numbers"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden Rotation numbers.

1. 1. Modelling and simulation of turbulence subject to system rotation

   Författare :Olof Grundestam; Arne Johansson; Sharath Girimaji; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulations; least-squares method; turbulence model; nonlinear modelling; system rotation; streamline curvature; high-lift aerodynamics; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Simulation and modelling of turbulent flows under influence of streamline curvature and system rotation have been considered. Direct numerical simulations have been performed for fully developed rotating turbulent channel flow using a pseudo-spectral code. The rotation numbers considered are larger than unity. LÄS MER

3. 2. Computational dynamics – real and complex

   Författare :Anna Belova; Warwick Tucker; Denis Gaidashev; Àlex Haro Provinciale; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Continued fractions; Generating functions; Rotation numbers; Rigorous computations; Interval analysis; Interval arithmetic; Multipliers; Quadratic map; Kuramoto-Sivashinsky equation; Mathematics; Matematik;

   Sammanfattning : The PhD thesis considers four topics in dynamical systems and is based on one paper and three manuscripts.In Paper I we apply methods of interval analysis in order to compute the rigorous enclosure of rotation number. LÄS MER

4. 3. Effects of rotation and stratification on magnetic flux concentrations

   Författare :Illa Rivero Losada; Axel Brandenburg; Dan Kiselman; Robert Cameron; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi;

   Sammanfattning : The formation of magnetic flux concentrations in the Sun is still a matter of debate. One observable manifestations of such concentrations is sunspots. LÄS MER

5. 4. Combining Models of Coronal Mass Ejections and Solar Dynamos

   Författare :Jörn Warnecke; Axel Brandenburg; Juri Toomre; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetohydrodynamics; convection; turbulence; solar dynamo; solar rotation; solar activity; coronal mass ejections; Astronomy; astronomi;

   Sammanfattning : Observations show that Coronal Mass Ejections (CMEs) are associated with twisted magnetic flux configurations. Conventionally, CMEs are modeled by shearing and twisting the footpoints of a certain distribution of magnetic flux at the solar surface and letting it evolve at the surface. LÄS MER

7. 5. Analysis of laminar and turbulent flows with turbomachinery, biotechnology and biomechanical applications

   Författare :Gustaf Mårtensson; Arne Johansson; Gertjan van Heijst; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : The goal of this study was initially to gain a better understanding of the effects of rotation on turbulent flow in ducts. Knowledge concerning the influence of rotation on the structures of turbulence is of fundamental importance in many applications, e.g. LÄS MER