Sökning: "Turbulent flows"

Visar resultat 11 - 15 av 284 avhandlingar innehållade orden Turbulent flows.

  1. 11. Numerical Investigation of Turbulent Fluid Flow and Heat Transfer in Complex Ducts

    Författare :Masoud Rokni; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SED; WET; GGDH; RNG; RSM; EASM; Low-Reynolds; Non-linear k-e; Heat transfer; Turbulent; Complex ducts; Secondary flows; Temperature invariance; Energy research; Energiforskning;

    Sammanfattning : Th need for a reliable and reasonable accurate turbulence model without specific convergence problem for calculating duct flows in industrial applications has become more evident. In this study a general computational method has been developed for calculating turbulent quantities in any arbitrary three dimensional duct. LÄS MER

  3. 12. 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

  4. 13. Experimental study on turbulent boundary-layer flows with wall transpiration

    Författare :Marco Ferro; Jens Fransson; Bengt Fallenius; Joseph Klewicki; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent boundary layer; boundary-layer suction; boundary-layer blowing; wall-bounded turbulent flows; self-sustained turbulence; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : Wall transpiration, in the form of wall-normal suction or blowing through a permeable wall, is a relatively simple and effective technique to control the behaviour of a boundary layer. For its potential applications for laminar-turbulent transition and separation delay (suction) or for turbulent drag reduction and thermal protection (blowing), wall transpiration has over the past decades been the topic of a significant amount of studies. LÄS MER

  5. 14. Experimental study of turbulent flows through pipe bends

    Författare :Athanasia Kalpakli; P. Henrik Alfredsson; Ramis Örlü; Christoph Brücker; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent flow; swirl; pulsation; pipe bend; hot-wire anemometry; cold-wire anemometry; laser Doppler velocimetry; stereoscopic particle image velocimetry.;

    Sammanfattning : This thesis deals with turbulent flows in 90 degree curved pipes of circular cross-section. The flow cases investigated experimentally are turbulent flow with and without an additional motion, swirling or pulsating, superposed on the primary flow. LÄS MER

  7. 15. Model predictions of turbulent gas-particle shear flows

    Författare :Tobias Strömgren; Gustav Amberg; Arne V. Johansson; Martin Sommerfeld; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulent gas-particle flows; modelling; turbophoresis; two-way coupling; particle-particle collisions; numerical simulations; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : A turbulent two-phase flow model using kinetic theory of granularflows for the particle phase is developed and implmented in afinite element code. The model can be used for engineeringapplications. However, in this thesis it is used to investigateturbulent gas-particle flows through numerical simulations. LÄS MER