Sökning: "passive scalar mixing"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden passive 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. 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

4. 3. Turbulence measurements in fiber suspension flows : experimental methods and results

   Författare :Monika Carina Fällman; Fritz Bark; Daniel Söderberg; Fredrik Lundell; Thomas Wikström; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid; flow; turbulent; turbulence; paper; pulp; fiber; fibre; suspension; two-phase; experimental; conductivity; micro-probes; passive scalar; ultrasonic; Doppler shift; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Turbulent mixing is present in many pulp and paper processes. It is a particularly important factor in the design and improvements of the paper machine headbox, influencing the final paper structure. LÄS MER

5. 4. 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

7. 5. Experimental studies in jet flows and zero pressure-gradient turbulent boundary layers

   Författare :Ramis Örlü; P. Henrik Alfredsson; Tim B. Nickels; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Axisymmetric jet; swirling jet; coaxial jet; heated jet; zero pressuregradient turbulent boundary layer; wall-bounded turbulent flows; overlap region; passive scalar mixing; hot-wire anemometry; spatial resolution.; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : This thesis deals with the description and development of two classical turbulent shear flows, namely free jet and flat plate turbulent boundary layer flows. In both cases new experimental data has been obtained and in the latter case comparisons are also made with data obtained from data bases, both of experimental and numerical origin. LÄS MER