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Visar resultat 1 - 5 av 1295 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Large Eddy Simulations of Separated Compressible Flows around Wing Sections

   Författare :Jörgen Held; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; subgrid-scale; shock-boundary layer interaction; wing section; transonic; subsonic; compressible; separated; Large eddy simulation; LES; PVM; Mechanical engineering; hydraulics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

   Sammanfattning : This thesis concerns numerical calculations of compressible separated flows, with and without shocks, around wing sections using Large Eddy Simulations (LES). The considered geometries are the NACA 0012 wing section and the ONERA AT15A wing section. LÄS MER

3. 2. Experimental Studies of Separated Flow and Heat Transfer in a Ribbed Channel

   Författare :Lei Wang; Värmeöverföring; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energiforskning; plasma; Energy research; fluiddynamik; Gaser; fluid dynamics; plasmas; Gases; Particle image velocimetry; Liquid crystal thermography; ribbed channel; heat transfer; turbulence properties; separated flow; coherent structures;

   Sammanfattning : The main concern of this thesis is to experimentally investigate the turbulent flow and heat transfer in a ribbed channel. Such flows are encountered in many engineering applications, e.g., gas turbine cooling. LÄS MER

4. 3. Modal Decomposition of Separated Nozzle Flow

   Författare :Ragnar Larusson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Arnoldi; axisymmetric convergent-divergent nozzle; Mode Decomposision; Flow Separation; Resonance.; Dynamic Mode Decomposision; Computational Fluid Dynamics;

   Sammanfattning : The applicability of two different eigenvalue algorithms coupled with an axisymmetric RANS solver to predict the eigenmodes of separated supersonic flow inside an axisymmetric convergent-divergent nozzle was investigated. These are the Arnoldi and the Dynamic Mode Decomposition (DMD) algorithms, respectively. LÄS MER

5. 4. Communicating references in geographically separated collaborative work : an exploratory study

   Författare :Åsa Holm; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Industrial Work Environment; Industriell produktionsmiljö;

   Sammanfattning : This thesis is about collaboration between geographically separated small enterprises and how they manage their collaborative efforts. The issue has been explored by studying how the collaborating colleagues handle references during telephone conversations. LÄS MER

7. 5. Acquisition strategies for fat/water separated MRI

   Författare :Henric Rydén; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : This thesis focuses on new ways to more efficiently acquire the signal for fat/water separated MRI, also known as Dixon methods. In paper I, the concept of dual bandwidths was introduced to improve SNR efficiency by removing dead times in a spin echo PROPELLER sequence. LÄS MER