Search for dissertations about: "direct numerical simulations."

Showing result 1 - 5 of 175 swedish dissertations containing the words direct numerical simulations..

  2. 1. Direct numerical simulations of the rotating-disk boundary-layer flow

    Author : Ellinor Appelquist; Philipp Schlatter; Henrik Alfredsson; Rebecca Lingwood; Christopher Davies; KTH; []
    Keywords : Fluid mechanics; boundary layer; rotating disk; laminar-turbulent transition; convective instability; absolute instability; secondary instability; crossflow instability; direct numerical simulations; Teknisk mekanik; Engineering Mechanics;

    Abstract : This thesis deals with the instabilities of the incompressible boundary-layer flow that is induced by a disk rotating in otherwise still fluid. The results presented are mostly limited to linear instabilities derived from direct numerical simulations (DNS) but with the objective that further work will focus on the nonlinear regime, providing greater insights into the transition route to turbulence. READ MORE

  4. 2. 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

  5. 3. The rotating-disk boundary-layer flow studied through numerical simulations

    Author : Ellinor Appelquist; Philipp Schlatter; Henrik Alfredsson; Rebecca Lingwood; Benoît Pier; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; laminar-turbulent transition; convective instability; absolute instability; crossflow instability; direct numerical simulations; Fysik; Physics;

    Abstract : This thesis deals with the instabilities of the incompressible boundary-layer flow thatis induced by a disk rotating in otherwise still fluid. The results presented include bothwork in the linear and nonlinear regime and are derived from direct numerical sim-ulations (DNS). READ MORE

  6. 4. Droplet growth in atmospheric turbulence : A direct numerical simulation study

    Author : Xiang-Yu (李翔宇) Li; Gunilla Svensson; Axel Brandenburg; Wojciech Grabowski; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; cloud micro-physics; turbulence; inertial particles; DNS; condensation; collision; coalescence; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Abstract : This Ph.D. thesis examines the challenging problem of how turbulence affects the growth of cloud droplets in warm clouds. Droplets grow by either condensation or collision. READ MORE

  7. 5. Spectral-element simulations of separated turbulent internal flows

    Author : Johan Ohlsson; Dan Prof Henningson; Jesper Oppelstrup; KTH; []
    Keywords : spectral element method; direct numerical simulations DNS ; turbulence; dealiasing; three-dimensional separation; massively parallel simulations;

    Abstract : .... READ MORE