Sökning: "scalar mixing"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden scalar mixing.

1. 1. Experimental study of passive scalar mixing in swirling jet flows

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

   Sammanfattning : 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. LÄS MER

3. 2. Fluxes and Mixing Processes in the Marine Atmospheric Boundary Layer

   Författare :Erik Olof Nilsson; Anna Rutgersson; Harm Jonker; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Waves; Growing sea; Swell; Marine boundary layer; Air-sea interaction; Mixing; Momentum flux; Wind stress; Flux attenuation; Sensor separation; Large eddy simulation; Multiresolution analysis; Coupling; Wave model; Climate model; Wave age; Meteorology; Meteorologi;

   Sammanfattning : Atmospheric models are strongly dependent on the turbulent exchange of momentum, sensible heat and moisture (latent heat) at the surface. Oceans cover about 70% of the Earth’s surface and understanding the processes that control air-sea exchange is of great importance in order to predict weather and climate. LÄS MER

4. 3. On the modelling of turbulent flow and mixing in stirred reactors

   Författare :Johan Revstedt; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; CFD; stirred reactors; impeller modelling; Energy research; mixing; LES; Energiforskning;

   Sammanfattning : This thesis concerns the numerical simulations and modelling of the flow structure and scalar transport in stirred reactors. For this Large Eddy Simulations (LES) have been used. The flow situation in a stirred reactor includes several flow phenomena that are not well predicted by "standard" two-equation models, e.g. LÄS MER

5. 4. Experimental Studies of Turbulent Mixing in Impinging Jets

   Författare :Rong Ding; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LDV; Gases; fluid dynamics; plasmas; Gaser; fluiddynamik; plasma; PIV LIF; TR- LIF; TR- PIV; perturbed- and swirling- impinging jets; passive control; frequency spectrum; turbulent fluxes; impinging jets; turbulent mixing;

   Sammanfattning : This thesis concerns the experimental study of mixing and flow characteristic in turbulent circular impinging jets without and with jet orifice manipulators (i.e. passive-fixed perturbations atthe nozzle exit), without and with swirl. LÄS MER

7. 5. Dynamics of bubbles across scales

   Författare :Niklas Hidman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DNS; multiscale; lift force; scalar mixing; Bubbly flows; multiphase;

   Sammanfattning : This thesis presents numerical investigations of bubbly flow phenomena across a wide range of relevant spatial and temporal scales. The aim is to increase our understanding of a great variety of underlying phenomena and to facilitate improved predictions of bubbly flows at all relevant scales. LÄS MER