Sökning: "convective heat transfer"

Visar resultat 11 - 15 av 61 avhandlingar innehållade orden convective heat transfer.

1. 11. Numerical Investigation of Turbulent Fluid Flow and Heat Transfer in Complex Ducts

   Författare :Masoud Rokni; Värmeöverföring; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SED; WET; GGDH; RNG; RSM; EASM; Low-Reynolds; Non-linear k-e; Heat transfer; Turbulent; Complex ducts; Secondary flows; Temperature invariance; Energy research; Energiforskning;

   Sammanfattning : Th need for a reliable and reasonable accurate turbulence model without specific convergence problem for calculating duct flows in industrial applications has become more evident. In this study a general computational method has been developed for calculating turbulent quantities in any arbitrary three dimensional duct. LÄS MER

3. 12. Prediction of forced convection heat transfer to Lead-Bismuth-Eutectic

   Författare :Roman Thiele; Henryk Anglart; Martin Rohde; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Lead-bismuth-eutectic; Forced convective heat transfer; Turbulence-modeling; GEN-IV reactors;

   Sammanfattning : The goal of this work is to investigate the capabilities of two different commercial codes, OpenFOAM and ANSYS CFX, to predict forced convection heat transfer in low Prandtl number fluids and investigate the sensitivity of these predictions to the type of code and to several input parameters.The goal of the work is accomplished by predicting forced convection heat transfer in two different experimental setups with the codes OpenFOAM and ANSYS CFX using three different turbulence models and varying the input parameters in an extensive sensitivity analysis. LÄS MER

4. 13. Combustion, Fluid Dynamics and Heat Transfer in Oxy-fuel and Air-Fired CFB boilers

   Författare :Sadegh Seddighi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carbon Capture and Storage; Combustion; Circulating Fluidized Bed; Oxy-Fuel; Multi-Phase Reacting Flow; Boiler Design; Emission; Fluid Dynamics; Heat Transfer;

   Sammanfattning : The studies described in this thesis develop and encode modeling tools for the design and scale-up of oxy-fuel circulating fluidized bed (CFB) boilers across a wide range of operational conditions. The modeling comprises fluid dynamics, combustion, and heat transfer and uses expressions that are proposed in this work or derived from the literature, together with experimental data obtained under both oxy-fuel-fired and air-fired conditions. LÄS MER

5. 14. Natural Convection Heat Transfer in a Horizontal Thermal Insulation Layer Underlying an Air Layer

   Författare :Mihail Serkitjis; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; air layer; thermal insulation; composite system; heat transfer; numerical simulation; natural convection; porous layer; measurements; testing equipment;

   Sammanfattning : In the thesis a study is made of the influence of natural convection on heat transfer in a composite system comprising a porous material heated from below and an air space situated above this. The measuring apparatus, a Wind Box which has been designed and developed at the Department of Building Physics is described. LÄS MER

7. 15. Transport Coefficients during Drying of Solids containing Multicomponent Mixtures

   Författare :Rafael Gamero; Joaquín Martínez; Evangelos Tsotsas; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; capillary; conduction; convection; diffusion; evaporation; heat transfer; hydraulic conductivity; liquid film; liquid transport; mass transfer; Maxwell-Stefan diffusion coefficients; molar fluxes; phase equilibrium; temperature gradient; ternary mixture; thermodynamic factors; Chemical engineering; Kemiteknik;

   Sammanfattning : This study investigated the transport coefficients involved in mass and heat transfer during the drying of a porous solid partially saturated with multicomponent mixtures.  It included the coefficients governing liquid transport through the solid, the matrix of multicomponent diffusion coefficients in the liquid phase, and the effective thermal conductivity. LÄS MER