Search for dissertations about: "DDES"

Found 3 swedish dissertations containing the word DDES.

  1. 1. Integrated Duct Aerodynamics

    University dissertation from ; Chalmers tekniska högskola; Gothenburg

    Author : Elias Siggeirsson; [2018]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DDES; RANS; CFD; Compressor duct; Spalart-Allmaras;

    Abstract : Air traffic is rapidly increasing, with no sign of slowing down, resulting in increased green-house gases emission. With emission criteria becoming stricter every year, the aircraft design is subjected to continuous improvements. The development of more efficient aircraft engines plays a central role in the strive towards lower emission levels. READ MORE

  2. 2. Turbulence-resolving Simulations of Swirling Flows

    University dissertation from ; Chalmers tekniska högskola; Gothenburg

    Author : Ardalan Javadi; [2016]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Swirling Flow; URANS; Hydropower; Hybrid URANS-LES; SAS; Flow Control; Turbulence Modeling; Vortex Breakdown; DDES; LES;

    Abstract : 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. READ MORE

  3. 3. Slipstream and Flow Structures in the Near Wake of High-Speed Trains

    University dissertation from Stockholm : KTH Royal Institute of Technology

    Author : Tomas W. Muld; KTH.; KTH.; [2012]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Train transportation is a vital part of the transportation system of today. Asthe speed of the trains increase, the aerodynamic effects become more impor-tant. One aerodynamic effect that is of vital importance for passengers’ andtrack workers’ safety is slipstream, i.e. READ MORE