Search for dissertations about: "turbulence modification"

Showing result 1 - 5 of 14 swedish dissertations containing the words turbulence modification.

2. 1. On Particle Transport and Turbulence Modification in Air-Particle Flows

   Author : Camilla Ljus; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; turbulent dispersion; hot film probe; turbulence measurements; turbulence modification; particle transport; two-fluid model;

   Abstract : The transport of particles by airflow was studied for two different flow cases, the transport of pulp fibres in a mat-forming process and the transport of pulp fibres and spherical particles in a horizontal pipe. The transport of pulp fibres in the mat-forming process is first considered. READ MORE

4. 2. Experimental study of passive scalar mixing in swirling jet flows

   Author : Ramis Örlü; Henrik Alfredsson; Peter Johansson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; swirling jet; turbulence; passive scalar; mixing; hot-wire anemometry; cold-wire; Fluid mechanics; Strömningsmekanik;

   Abstract : Despite its importance in various industrial applications there is still a lack of experimental studies on the dynamic and thermal field of swirling jets in the near-field region. The present study is an attempt to close this lack and provide new insights on the effect of rotation on the turbulent mixing of a passive scalar, on turbulence (joint) statistics as well as the turbulence structure. READ MORE

5. 3. 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

6. 4. Secondary Electromagnetic Radiation Generated by HF Pumping of the Ionosphere

   Author : Lars Norin; Bo Thidé; Savely M. Grach; Bengt Gustafsson; James W. LaBelle; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; space physics; ionospheric modification experiments; plasma turbulence; stimulated electromagnetic emission; ionospheric irregularities; radio waves; parametric processes; thermal parametric instability; transient dynamics; wave-wave interactions; Physics; Fysik;

   Abstract : Electromagnetic waves can be used to transmit information over long distances and are therefore often employed for communication purposes. The electromagnetic waves are reflected off material objects on their paths and interact with the medium through which they propagate. READ MORE

7. 5. Turbulence Modelling for Internal Cooling of Gas-Turbine Blades

   Author : Jonas Bredberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Numerical simulations of geometrical configurations similar to those present in the internal cooling ducts within gas turbine blades have been performed. The flow within these channels are characterized by heat transfer enhancement ribs, sharp bends, rotation and buoyancy effects. READ MORE