Search for dissertations about: "LES"

Showing result 1 - 5 of 250 swedish dissertations containing the word LES.

  1. 1. Methodologies for RANS-LES interfaces in turbulence-resolving simulations

    Author : Sebastian Arvidson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; zonal RANS-LES; aeronautics; RANS-LES interfaces; Hybrid RANS-LES; grey-area mitigation; log-layer mismatch; embedded LES; LES length scale; LES;

    Abstract : Hybrid Reynolds-Average Navier-Stokes (RANS)-Large-Eddy Simulations (LES) techniques are now seen by the aeronautical industry as the most promising turbulence-resolving approaches for complex high-Reynolds-number turbulent flows with regard to cost and accuracy. However, connecting RANS and LES simulated flows is a challenging task and needs special attention in order to increase simulation robustness and accuracy. READ MORE

  2. 2. 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

  3. 3. Flow Duct Acoustics : An LES Approach

    Author : Emma Alenius; Mats Åbom; Laszlo Fuchs; Oliver Paschereit; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aero-acoustics; duct-acoustics; sound generation; acoustic scattering; acoustic-flow interaction; LES; IC-engines; orifice plate; confined jet;

    Abstract : The search for quieter internal combustion engines drives the quest for a better understanding of the acoustic properties of engine duct components. Simulations are an important tool for enhanced understanding; they give insight into the flow-acoustic interaction in components where it is difficult to perform measurements. READ MORE

  4. 4. Compressible Turbulent Flows : LES and Embedded Boundary Methods

    Author : Marco Kupiainen; Bjorn Engquist; William Henshaw; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Embedded Boundary methods; Compressible flow; turbulent flow; Numerical analysis; Numerisk analys; Computational physics; Beräkningsfysik; Fluid mechanics; Strömningsmekanik;

    Abstract : .... READ MORE

  5. 5. Class, Place and Identity in a Satellite Town

    Author : Elias le Grand; Patrik Aspers; Lars Udehn; Les Back; Stockholms universitet; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; class; identity; place; chav; stigma; symbolic boundaries; youths; moral panics; Sociology; Sociologi; Sociology; sociologi;

    Abstract : The central aim of this study is to examine processes of identity formation among white, working-class youths in a marginalized area located on the outskirts of South London. It is primarily based on long-term ethnographic fieldwork but also on analyses of web sites, newspapers and popular culture. READ MORE