Search for dissertations about: "POD"

Showing result 1 - 5 of 64 swedish dissertations containing the word POD.

2. 1. 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

4. 2. Impacts of alternative combustion diluents and hydrogen addition on a swirl-stabilized flame related to gas turbine application

   Author : Mao Li; Kraftverksteknik; []
   Keywords : lean premixed combustion; Swirl-stabilized flame; Gas turbine combustion; Flame dilution; H2 addition; Lean blowout; CO emission; PVC; CH chemiluminescence; Inverse Abel transform; PIV; POD;

   Abstract : The global energy tendency leads to increasing attention on clean combustion technologies in order to eliminate adverse impacts on the environment. The utilization of oxyfuel combustion (CO2 acts as the only combustion dilution), flame diluents, and hydrogen fuel in gas turbine combustion provides a promising solution to reduce combustion pollutant emissions. READ MORE

5. 3. Drag Reduction by means of Active Flow Control Applied on a Generic Truck A-pillar: a Numerical and Experimental Study

   Author : Guglielmo Minelli; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PANS; Large Eddy Simulation; Wind Tunnel.; Bluff Body Flow; Modal Decomposition; Experiments; Vehicle Aerodynamic; POD; Active Flow Control; LES; Partially Averaged Navier Stokes; AFC;

   Abstract : The overall goal of this thesis is to isolate and control the flow mechanism characterizing the flow separation occurring at the A-pillar of a truck. The study aims to gain knowledge of the flow physics of the separation mechanism, and to eventually suppress the afore mentioned separation by means of an Active Flow Control. READ MORE

6. 4. 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. 5. 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