Sökning: "two-phase heat transfer"

Visar resultat 11 - 15 av 31 avhandlingar innehållade orden two-phase heat transfer.

1. 11. Heat and Mass Transfer Investigations of Relevance for Food Engineering Applications

   Författare :Dirk Sterner; Värmeöverföring; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Thermal engineering; applied thermodynamics; Termisk teknik; termodynamik; mathematical modelling; frozen and non-frozen food; minced beef patties; cooking; heat and mass transfer; plate heat exchangers; evaporation;

   Sammanfattning : This thesis concerns two interrelated subjects of heat and mass transfer processes. The first one concerns mainly experimental measurements, with a subsequent development of a calculation procedure, of the thermal and hydraulic performances, experimental methods and evaluation procedures applied on various plate heat exchangers (PHEs) as evaporators with the refrigerant ammonia as working medium. LÄS MER

3. 12. Investigation of Thermal Performance of Cylindrical Heatpipes Operated with Nanofluids

   Författare :Morteza Ghanbarpourgeravi; Rahmatollah Khodabandeh; Björn Palm; Oronzio Manca; KTH; []
   Nyckelord :Nanofluid; heat pipe; thermal resistance; heat transfer coefficient; evaporator; condenser; wick; porous layer; heat flux; inclination angle; thermal conductivity; viscosity; Energiteknik; Energy Technology;

   Sammanfattning : Nanofluids as an innovative class of heat transfer fluids created by dispersing nanometre-sizedmetallic or non-metallic particles in conventional heat transfer fluids displayed the potential toimprove the thermophysical properties of the heat transfer fluids. The main purpose of this study is toinvestigate the influence of the use of nanofluids on two-phase heat transfer, particularly on thethermal performance of the heat pipes. LÄS MER

4. 13. Modeling of Pulverised Wood Flames

   Författare :Ashraf Elfasakhany; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; applied thermodynamics; Thermal engineering; Energiforskning; Energy research; plasma; combustion; pulverised wood; two-phase flow; devolatilization; emissions; Gases; fluid dynamics; plasmas; fluiddynamik; Gaser; Termisk teknik; termodynamik;

   Sammanfattning : The aim of the current work was at development and validation of modeling tools for simulation of pulverised wood flames in furnaces and study how different factors influence on such flames. The numerical model involves different sub-models for the physo-chemical processes, such as, two-phase flow motion, drying, devolatilization and shrinkage of particles, the formation and oxidation of volatile, tar and char, turbulence-chemistry interaction, turbulence-radiation interaction, etc. LÄS MER

5. 14. Numerical Modelling of Subcooled Nucleate Boiling for Thermal Management Solutions Using OpenFOAM

   Författare :Achref Rabhi; Rebei Bel Fdhila; Konstantinos Kyprianidis; Ioanna Aslanidou; Christophe Duwig; Mälardalens universitet; []
   Nyckelord :Computational Fluid Dynamics; Boiling Flows; Two-phase cooling; Energy- and Environmental Engineering; energi- och miljöteknik;

   Sammanfattning : Two-phase cooling solutions employing subcooled nucleate boiling flows e.g. thermosyphons, have gained a special interest during the last few decades. This interest stems from their enhanced ability to remove extremely high heat fluxes, while keeping a uniform surface temperature. LÄS MER

7. 15. Weld Pool Simulations

   Författare :Marcus Edstorp; Högskolan Väst; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Arc Welding; Weld Pool; Multiphysics Simulations; Moving Boundaries; Free Surfaces; Mesh Motion; Two-Phase Flow; Incompressible Flow; Electromagnetics; Finite Element Methods; Applied mathematics; Tillämpad matematik; Manufacturing engineering; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik; Arc Welding; Weld Pool; Multiphysics Simulations; Moving Boundaries; Free Surfaces; Mesh Motion; Two-Phase Flow; Incompressible Flow; Electromagnetics; Finite Element Methods;

   Sammanfattning : This investigation is devoted to the study of welding and its effect on the workpiece, focusing on the thermo and fluid dynamical phenomena occuring during a autogenous or nonautogenous arc fusion welding process. Its aim is to simulate the behaviour of the weld pool and analyze the consequence of the solid-liquid phase change, thus obtaining a methodology for predicting the appearance of weld defects related to solidification and cooling. LÄS MER