Search for dissertations about: "critical heat flux"

Showing result 1 - 5 of 24 swedish dissertations containing the words critical heat flux.

  1. 1. Pool Boiling on Structured Surfaces: Heat Transfer and Critical Heat Flux : -Experiments and Mechanistic Modelling

    University dissertation from Department of Energy Sciences, Lund University

    Author : Zhen Cao; [2019-09-30]
    Keywords : pool boiling; heat transfer; critical heat flux; bubble dynamics; surface modification;

    Abstract : In this thesis, pool boiling heat transfer was experimentally studied on structured surfaces with dielectric liquids (HFE-7200, NOVEC-649, FC-72), organic liquids (Acetone, Pentane) and deionized water.In the first step, nanoparticle coatings on copper surfaces were prepared by an electrophoretic deposition method, with Cu-Zn nanoparticles (100 nm) and Cu nanoparticles (150 nm). READ MORE

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

    University dissertation from Stockholm : KTH

    Author : Claudi Martin Callizo; Björn Palm; Predrag Hrnjak; [2010]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microchannel; heat exchanger; heat transfer; flow boiling; flow patterns; onset of nucleate boiling; dryout; critical heat flux; TECHNOLOGY Engineering mechanics Mechanical and thermal engineering; TEKNIKVETENSKAP Teknisk mekanik Mekanisk och termisk energiteknik;

    Abstract : 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. READ MORE

  3. 3. Limiting conditions for a sustained flame over condensed fuels : Analysis by experiments and stagnant layer theory

    University dissertation from Division of Fire Safety Engineering, Lund University

    Author : Frida Vermina Plathner; [2020]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Critical mass flux; diffusion flame; extinction; sustained ignition; chemical heat of combustion; Convective heat transfer coefficient; external heat flux;

    Abstract : Ignition and extinction characteristics of a material determine whether a fire will be initiated and grow. In fire safety engineering, where modellers deal with a multitude of materials, simplified thresholds are commonly used to determine when ignition and extinction occur. READ MORE

  4. 4. An Experimental Study on Micro-Hydrodynamics of Evaporating/Boiling Liquid Film

    University dissertation from Division of Fire Safety Engineering, Lund University

    Author : Shengjie Gong; Ma Weimin; Horst-Michael Prasser; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; liquid film; critical thickness; boiling; critical heat flux; rupture; dry spot; confocal optical sensor; SRA - Energy; SRA - Energi;

    Abstract : Study of liquid film dynamics is of significant importance to the understanding and control of various industrial processes that involve spray cooling (condensation), heating (boiling), coating, cleaning and lubrication. For instance, the critical heat flux (CHF) of boiling heat transfer is one of the key parameters ensuring the efficiency and safety of nuclear power plants under both operational and accident conditions, which occurs as the liquid layers (microlayer and macrolayer) near the heater wall lose their integrity. READ MORE

  5. 5. Assessment and improvements of thermal-hydraulic correlations and methods for the analysis of the Jules Horowitz Reactor

    University dissertation from Gothenburg : Chalmers tekniska högskola

    Author : Alberto Ghione; [2017]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Flow instability; Uncertainty; Narrow channels; Jules Horowitz Reactor; Safety analysis; Critical heat flux; Thermal-hydraulic correlations; Heat transfer; Best-Estimate; Material Testing Reactor;

    Abstract : Nuclear research reactors are used to test materials for current and future nuclear technologies, and to produce radioisotopes for medical purposes. Most of the existing Material Testing Reactors in Europe have operated for more than 50 years and new ones are needed. READ MORE