Sökning: "passive scalar"

Visar resultat 11 - 15 av 18 avhandlingar innehållade orden passive scalar.

1. 11. 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

3. 12. 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

4. 13. Subgrid-scale modelling for large-eddy simulation including scalar mixing in rotating turbulent shear flows

   Författare :Linus Marstorp; Arne Johansson; Lars-Erik Eriksson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; large-eddy simulation; subgrid-scale model; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : The aim of the present study is to develop subgrid-scale models that are relevant for complex flows and combustion. A stochastic model based on a stochastic Smagorinsky constant with adjustable variance and time scale is proposed. LÄS MER

5. 14. A study of turbulence and scalar mixing in a wall-jet using direct numerical simulation

   Författare :Daniel Ahlman; Arne V. Johansson; Lars-Erik Eriksson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningmekanik; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Direct numerical simulation is used to study the dynamics and mixing in a turbulent plane wall-jet. The investigation is undertaken in order to extend the knowledge base of the influence of the wall on turbulent dynamics and mixing. The mixing statistics produced can also be used to evaluate and develop models for mixing and combustion. LÄS MER

7. 15. Numerical studies of turbulent wall-jets for mixing and combustion applications

   Författare :Daniel Ahlman; Arne Johansson; Geert Brethouwer; Micheal Manhart; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Direct numerical simulation is used to study turbulent plane wall-jets. The investigation is aimed at studying dynamics, mixing and reactions in wall bounded flows. The produced mixing statistics can be used to evaluate and develop models for mixing and combustion. LÄS MER