Sökning: "swirl flow"

Visar resultat 21 - 25 av 93 avhandlingar innehållade orden swirl flow.

  1. 21. Time-accurate Turbulence Modeling of Swirling Flow for Hydropower Application

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

    Sammanfattning : Hydraulic turbomachines have played a prominent role in the procurement of renewableenergy for more than a century. Embedded in the context of general technological progress,their design for efficiency and reliability has reached an outstanding level of quality. LÄS MER

  3. 22. Swirl stabilized premixed flame analysis using of LES and POD

    Författare :Piero Iudiciani; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Precessing Vortex Core; Swirl stabilization; Lean Premixed Combustion; Proper Orthogonal Decomposition; Large Eddy Simulation;

    Sammanfattning : For environmental and human health reasons, the regulations on the emissions from combustion devices are getting more and more strict. In particular, it is important to abate the emission of pollutants deriving from combustion in gas turbines. A solution is the use of swirl stabilized, lean premixed combustion. LÄS MER

  4. 23. 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

  5. 24. Turbulence Measurements in a Natural Convection Boundary Layer and a Swirling Jet

    Författare :Abolfazl Shiri; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swirl; constant current bridge; high Rayleigh number; natural convection; Jet; cold-wire thermometry; vertical cylinder; laser Doppler anemometry; turbulent boundary layers;

    Sammanfattning : Two sets of experimental measurement were carried out on an axisymmetric swirling jet flow and a natural convection boundary layer. In the first experiment, the far field of an incompressible swirling jet, discharged into a quiescent ambient has been studied using laser Doppler anemometry. LÄS MER

  7. 25. Numerical and experimental investigation of a gasturbine model combustor with axial swirler

    Författare :Michael Bertsch; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flashback; swirl; gasturbine; combustor; methane; hydrogen; LES; PLIF;

    Sammanfattning : This thesis presents the simulations of and experiments with the so-called CECOST burner. The CECOST burner is a gas turbine model combustor equipped with an axial swirler and placed in a laboratory for the lean premixed turbulent combustion of a range of fuels at atmospheric pressure. LÄS MER