Search for dissertations about: "proper orthogonal decomposition POD"

Showing result 6 - 10 of 31 swedish dissertations containing the words proper orthogonal decomposition POD.

  2. 6. Large Eddy Simulations of Complex Flows in IC-Engine's Exhaust Manifold and Turbine

    Author : Johan Fjällman; Laszlo Fuchs; Mihai Mihaescu; Ricardo Martinez-Botas; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large Eddy Simulations; Reynolds Averaged Navier-Stokes; Turbocharger; Turbine; Curved Pipes; Pulsatile Flow; Proper Orthogonal Decomposition; Large Eddy Simulations; Reynolds Averaged Navier-Stokes; Turboladdare; Turbin; Rörkrök; Pulserande Flöde; Proper Orthogonal Decomposition; Engineering Mechanics; Teknisk mekanik;

    Abstract : The thesis deals with the flow in pipe bends and radial turbines geometries that are commonly found in an Internal Combustion Engine (ICE). The development phase of internal combustion engines relies more and more on simulations as an important complement to experiments. READ MORE

  4. 7. A Particle Image Velocimetry Study of Bubbly Gas-Liquid Flow

    Author : Xiaoyun Tu; Livsmedelsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulent dispersion; Food and drink technology; Livsmedelsteknik; turbulence; Rushton turbine; stirred tank; slip velocity; bubbly gas liquid two-phase flow; coherent structure; CCD camera; PIV; POD;

    Abstract : The aim of this work is to build a framework that can be used for characterizing the bubbly gas liquid turbulent flow in the stirred bioreactor tank. To this end we have developed and modified techniques with which to measure the velocity of both dispersed gas and carrier liquid phases by the optical measurement technique, a 2-CCD camera Particle Image Velocimetry (PIV) system; and to characterize the turbulence by the wavelets tool, Proper Orthogonal Decomposition (POD). READ MORE

  5. 8. Numerical predictions of heat-transfer applied to electrical machines

    Author : Kristian Rönnberg; Christophe Duwig; Anders Dahlkild; Luca Peretti; Jens Honore Walther; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric machines; energy efficiency; heat transfer; thermal management; high fidelity simulation; computational fluid dynamics CFD ; proper orthogonal decomposition POD ; lumped parameter thermal network LPTN ; Elektriska maskiner; energieffektivitet; verkningsgrad; värmeöverföring; värmehantering; simuleringar med hög upplösning; strömningsmekaniska beräkningar; proper orthogonal decomposition POD ; termiska nätverk; Teknisk mekanik; Engineering Mechanics;

    Abstract : In order to meet the need for increased electrification, and at the same time reduce the total demand for electric energy, behavior change and technological innovation is needed. Over the decades power density of electric motors have increased, leading to increased demands on the cooling system design and performance. READ MORE

  6. 9. Active Control and Modal Structures in Transitional Shear Flows

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

    Abstract : 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. READ MORE

  7. 10. Spectral-element simulations of turbulent wall-bounded flows including transition and separation

    Author : Johan Malm; Dan Henningson; Philipp Schlatter; Suad Jakirlic; KTH; []
    Keywords : spectral-element method; direct numerical simulation DNS ; large-eddy simulation LES ; turbulence; transition; over-integration; three-dimensional separation; massively parallel simulations; proper orthogonal decomposition POD ; Koopman modes; vorticity stretching; coherence; SRA - E-vetenskap SeRC ; SRA - E-Science SeRC ;

    Abstract : The spectral-element method (SEM) is used to study wall-bounded turbulent flowsin moderately complex geometries. The first part of the thesis is devoted to simulations of canonical flow cases, such as temporal K-type transitionand turbulent channel flow, to investigate general resolution requirements and computational efficiency of the numerical code nek5000. READ MORE