Sökning: "Swirling Flows"

Visar resultat 1 - 5 av 39 avhandlingar innehållade orden Swirling Flows.

  1. 1. Turbulence-resolving Simulations of Swirling Flows

    Författare :Ardalan Javadi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Swirling Flow; URANS; Hydropower; Hybrid URANS-LES; SAS; Flow Control; Turbulence Modeling; Vortex Breakdown; DDES; LES;

    Sammanfattning : A series of numerical investigations is undertaken using a wide range of turbulence mod-els including conventional and non-conventional URANS models, hybrid URANS-LESmethods and LES to capture a large variety of physical mechanisms that produce pres-sure pulsations in the swirling flows. The available knowledge about these pulsations,which are usual in hydropower, are still far from complete. LÄS MER

  3. 2. Large Eddy Simulation of Swirling Reacting Flows

    Författare :Mohammad Irannezhad; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Combustion; Swirling flow; Large Eddy Simulation;

    Sammanfattning : The combustion of fossil fuels remains a key technology as these fuels are the main source of energy in the foreseeable future. Heat released in combustion is often accompanied by emission of undesired soot, CO and NOx pollutants. LÄS MER

  4. 3. Analytical and Numerical Studies of Internal Swirling Flows

    Författare :Walter Gyllenram; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; vortex; draft tube; hydro turbine; filter; RANS; LES; swirling flow;

    Sammanfattning : Swirling flows are common in technical applications, e.g. turbines, pumps, fans, compressors and combustors. LÄS MER

  5. 4. 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

  7. 5. Large Eddy Simulation of Turbulent Swirling Flows in Combustor Related Geometries

    Författare :Yajing Wu; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Swirling flow; swirler; vortex breakdown; precessing vortex core PVC ; large eddy simulation LES .;

    Sammanfattning : This thesis deals with the physics of turbulent swirling flows. Large eddy simulation (LES) method is used to investigate the vortex breakdown process, the precessing vortex core (PVC), and the effect of swirl number and flow field configuration on swirling flows. The study is based on an open source CFD code, \textit{OpenFoam}. LÄS MER