Search for dissertations about: "isotropic turbulence"

Showing result 16 - 20 of 27 swedish dissertations containing the words isotropic turbulence.

  2. 16. Stability and Receptivity of Three-Dimensional Boundary Layers

    Author : David Tempelmann; Dan Henningson; Stefan Hein; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Receptivity; stability; optimal growth; three-dimensional boundary layers; parabolised stability equations; adjoint PSE; crossflow instability; Fluid mechanics; Strömningsmekanik;

    Abstract : The stability and the receptivity of three-dimensional flat plate boundary layers is studied employing parabolised stability equations. These allow for computationally efficient parametric studies. Two different sets of equations are used. READ MORE

  4. 17. Fluid and suspension hydrodynamics in the impeller discharge flow of stirred tanks

    Author : Ziyun Yu; KTH; []
    Keywords : hydrodynamics; stirred tank; phase Doppler anemometer;

    Abstract : The hydrodynamics of an agitated tank have been studied byphase-Doppler anemometry. The focus is on the impeller anddischarge region of a 45o pitched blade turbine (PBT). Thestudy includes agitation of pure water as well as of a dilutesuspension of process particles. READ MORE

  5. 18. Assessment and Some Improvements of Hybrid RANS-LES Methods

    Author : Sebastian Arvidson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; hybrid RANS-LES; zonal RANS-LES; embedded LES; PDH-LRN; log-layer mismatch; LES length scale; shock boundary-layer interaction;

    Abstract : Motivated by numerical analysis of a shock/boundary-layer interacting (SBLI) flow in a duct, where some typical existing hybrid RANS-LES methods become awkward to give accurate predictions of the shock-induced corner separation bubble, a new hybrid RANS-LES method, has been proposed. The model is based on a low-Reynolds-number (LRN) $k-\omega$ RANS model, which is one of the few models that are capable of giving reasonable predictions for the SBLI flow in RANS computations. READ MORE

  6. 19. Numerical study of non-spherical/spherical particles in laminar and turbulent flows

    Author : Mehdi Niazi Ardekani; Luca Brandt; Alfredo Pinelli; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : The presence of solid rigid particles alters the global transport and rheological properties of the mixture in complex (and often unpredictable) ways. In recent years a few studies have been devoted to investigating the behavior of dense suspensions in the turbulent/inertial regime with the majority of theses analyses limited to mono-disperse rigid neutrally-buoyant spheres. READ MORE

  7. 20. Direct Numerical Simulation and Modelling Study of the Structures and Propagation of Partially Premixed Turbulent Flames

    Author : Vivianne Holmen; Strömningsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Turbulent partially premixed flames are found in common combustion applications, such as the lifted jet flames in diesel engines. There is less theory surrounding the structure and propagation of turbulent partially premixed flames than for classical premixed flames and diffusion flames, especially in regards to modelling. READ MORE