Sökning: "proper orthogonal decomposition"

Visar resultat 26 - 30 av 49 avhandlingar innehållade orden proper orthogonal decomposition.

  1. 26. Model Order Reduction with Rational Krylov Methods

    Författare :K. Henrik A. Olsson; Axel Ruhe; Volker Mehrmann; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Model order reduction; dual rational Arnoldi; rational Krylov; moment matching; eigenvalue computation; stability analysis; heat exchanger model; Numerical analysis; Numerisk analys;

    Sammanfattning : Rational Krylov methods for model order reduction are studied. A dual rational Arnoldi method for model order reduction and a rational Krylov method for model order reduction and eigenvalue computation have been implemented. It is shown how to deflate redundant or unwanted vectors and how to obtain moment matching. LÄS MER

  3. 27. The Axisymmetric Turbulent Jet

    Författare :Stephan Gamard; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis aims at understanding the downstream evolution of the most energetic features of a turbulent axisymmetric jet. The study was conducted from 2 to 69 diameters downstream, using 3 different jet exit diameters with air flowing at a wide range of velocities to ensure a reasonable span of Reynolds numbers, while still keeping it in a high range, from 40,000 to 156,700. LÄS MER

  4. 28. Active Control and Modal Structures in Transitional Shear Flows

    Författare :Onofrio Semeraro; Dan Henningson; Bernd Noack; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow control; flat-plate boundary layer; optimal controllers; model reduction; turbulent jet; POD; DMD; Koopman modes;

    Sammanfattning : Flow control of transitional shear flows is investigated by means of numerical simulations. The attenuation of three-dimensional wavepackets of Tollmien-Schlichting (TS) and streaks in the boundary layer is obtained using active control in combination with localised sensors and actuators distributed near the rigid wall. LÄS MER

  5. 29. The Axisymmetric Turbulent Wake

    Författare :Peter Johansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis presents a theoretical and experimental study of the turbulent axisymmetric wake. In the theoretical part, an equilibrium similarity solution of the far wake was derived that was found to admit to two different solutions for this flow. LÄS MER

  7. 30. Studies on adverse-pressure-gradient turbulent boundary layers on wings

    Författare :Alvaro Tanarro; Philipp Schlatter; Ricardo Vinuesa; Omid Omidyeganeh; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The present licentiate thesis addresses the use of well-resolved simulations to simulate turbulent boundary layers (TBL) subjected to adverse pressure gradients. Within the thesis a wide variety of analyses are performed, and a method to improve the performance of the simulations is presented. LÄS MER