Sökning: "single-phase heat transfer"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden single-phase heat transfer.

1. 1. Single Phase Convective Heat Transfer with Nanofluids : An Experimental Approach

   Författare :Ehsan Bitaraf Hgahighi; Björn E. Palm; Elena V. Timofeeva; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nanofluid; convective heat transfer; thermal conductivity; viscosity; heat transfer coefficient; performance; pumping power; Reynolds number; shelf stability;

   Sammanfattning : Nanofluids (NFs) are engineered colloids of nanoparticles (NPs) dispersed homogenously within base fluids (BFs). Due to the presence of NPs, the thermophysical and transport properties of BFs are subject to change. LÄS MER

3. 2. Experimental Heat Transfer, pressure drop, and Flow Visualization of R-134a in Vertical Mini/Micro Tubes

   Författare :Wahib Owhaib; Björn Palm; Tassos Karayiannis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Minichannel; microchannel; heat transfer; pressure drop; single-phase; two-phase; flow boiling; flow visualization; dry out; bubble behavior; flow pattern.; Mechanical energy engineering; Mekanisk energiteknik;

   Sammanfattning : For the application of minichannel heat exchangers, it is necessary to have accurate design tools for predicting heat transfer and pressure drop. Until recently, this type of heat exchangers was not well studied, and in the scientific literature there were large discrepancies between results reported by different investigators. LÄS MER

4. 3. Improvement of the nuclear safety code CATHARE based on thermal-hydraulic experiments for the Jules Horowitz Reactor

   Författare :Alberto Ghione; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nuclear research reactor; fully developed boiling; single-phase heat transfer; CATHARE; laminar-turbulent transition; narrow rectangular channels; JHR; single-phase friction; SULTAN-JHR;

   Sammanfattning : The Jules Horowitz Reactor (JHR) is a material testing research reactor under construction at CEA-Cadarache (France). One of the computer codes employed in the safety analysis of this reactor is the thermal-hydraulic system code CATHARE. LÄS MER

5. 4. Flow Boiling Heat Transfer in Single Vertical Channels of Small Diameter

   Författare :Claudi Martin Callizo; Björn Palm; Predrag Hrnjak; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microchannel; heat exchanger; heat transfer; flow boiling; flow patterns; onset of nucleate boiling; dryout; critical heat flux; Mechanical and thermal engineering; Mekanisk och termisk energiteknik;

   Sammanfattning : Microchannel heat exchangers present many advantages, such as reduced size, high thermal efficiency and low fluid inventory; and are increasingly being used for heat transfer in a wide variety of applications including heat pumps, automotive air conditioners and for cooling of electronics.However, the fundamentals of fluid flow and heat transfer in microscalegeometries are not yet fully understood. LÄS MER

7. 5. Experimental Investigation of Refrigerant Charge Minimisation of a Small Capacity Heat Pump

   Författare :W. Primal D. Fernando; Björn Palm; Alberto Gavallini; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat pump; propane; low-charge; Wilson plot method; minichannels; aluminium heat exhangers; single.phase flow; Mechanical and thermal engineering; Mekanisk och termisk energiteknik;

   Sammanfattning : Enormous quantities of heat are available in air, soil, water, exhaust air from buildings, and in waste water of any kind. However these heat sources are use-less for heating purposes since their temperatures are lower than the tempera-ture required for heating. LÄS MER