Sökning: "turbulent natural convection"

Visar resultat 1 - 5 av 25 avhandlingar innehållade orden turbulent natural convection.

1. 1. DNS and LES of Turbulent Natural Convection Boundary Layer

   Författare :Darioush Gohari Barhaghi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DNS; free convection; LES; natural convection boundary layer; vertical cylinder;

   Sammanfattning : Turbulent natural convection boundary layers possess some special characteristicscompared to the other boundary layers.In order to study this kind of boundary layer, two powerful numerical methods,Direct Numerical Simulation or DNS and Large Eddy Simulation or LES,are used. LÄS MER

3. 2. A Study of Turbulent Natural Convection Boundary Layers Using Large-Eddy Simulation

   Författare :Darioush Gohari Barhaghi; Chalmers tekniska högskola; []
   Nyckelord :natural convection boundary layer; DNS; LES; radiation heat transfer; free convection; cavity; vertical cylinder;

   Sammanfattning : The structure of turbulent natural convection boundary layers in differentgeometries and the effect of the buoyancy on a mixed convection boundarylayer are investigated. These geometries comprise a vertical finitecylinder, a vertical infinite channel, a cavity and a vertical finite channel. LÄS MER

4. 3. Turbulent Forced Convection Air Cooling of Electronics with Heat Sinks Under Flow Bypass Conditions

   Författare :Hans Jonsson; KTH; []
   Nyckelord :forced convection; heat transfer; pressure drop; turbulent; air cooling; bypass; plate; strip; pin; fin; heat sink; electronics; experimental; numerical; CFD; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : Air cooling is still the dominant method for dissipating theheat produced by electronic components. In a typical electronicdevice, the components are situated on a Printed Circuit Board(PCB). For most applications natural convection is sufficientto cool the components. LÄS MER

5. 4. Modelling of Turbulent Flow and Heat Transfer for Building Ventilation

   Författare :Peng Shia-Hui; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; large eddy simulation; turbulent buoyant convection; ventilation performance assessment; purging flow rate; SGS modelling; ventilation flow; stochastic Markov chain model; turbulence modelling; LRN k-w model; two-equation models; building ventilation; transfer probability; transition regime; modified SGS buoyancy model; energy backscatter;

   Sammanfattning : This thesis contributes to studies on the assessment of building ventilation performance and the development of turbulence models accounting for Low-Reynolds-number (LRN) effects and buoyant convection with heat transfer. Assessments of building ventilation performance are discussed with respect to indoor air distribution and passive contaminant dispersion. LÄS MER

7. 5. 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