Sökning: "heat current"

Visar resultat 1 - 5 av 382 avhandlingar innehållade orden heat current.

  1. 1. Heat exposure and health outcomes in Costa Rican sugarcane harvesters

    Författare :Jennifer Crowe; Maria Nilsson; Tord Kjellström; Catharina Wesseling; Linda Forst; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Agricultural worker; Central America; Chronic kidney disease; Climate change; Dehydration; Heat; Heat illness; Heat stress; Sugarcane; Urinalysis; Worker health; folkhälsa; Public health; Epidemiology; epidemiologi;

    Sammanfattning : Background The remarkably efficient mechanisms of the human body to maintain its core temperature of 37°C can be inadequate when harsh climatic conditions and excessive muscle movement lead to heat stress, dehydration and potential heat illness, ranging from minor symptoms such as fatigue to a potentially fatal heat stroke. Agricultural workers in the tropics are at high risk, which is expected to increase with climate change. LÄS MER

  3. 2. Performance Analysis and Optimal Design of Heat Exchangers and Heat Exchanger Networks

    Författare :Lieke Wang; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; applied thermodynamics; Thermal engineering; flexibility; pinch technology; optimization; heat exchanger networks; thermal efficiency; multi-stream; plate-fin heat exchangers; plate heat exchangers; steam condensation; heat exchangers; Termisk teknik; termodynamik; Gases; fluid dynamics; plasmas; Gaser; fluiddynamik; plasma;

    Sammanfattning : This thesis presents a study on performance analysis and optimal design of heat exchangers and heat exchanger networks. The study includes an experimental investigation of steam condensation in plate heat exchangers, optimal design of plate heat exchangers and plate-fin heat exchangers, and optimization of heat exchanger networks. LÄS MER

  4. 3. Phase dependent heat transport in superconducting junctions with scattering theory

    Författare :Fatemeh Hajiloo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; heat transport; heat conductance; scattering theory; superconducting hybrid devices; conductance fluctuations; phase dependent heat currents;

    Sammanfattning : The operation of nanoscale devices at low temperatures is highly sensitive to heating effects. This motivates current research on controlling heat currents in these devices. LÄS MER

  5. 4. District heating in future Europe : Modelling expansion potentials and mapping heat synergy regions

    Författare :Urban Persson; Sven Werner; Lars J. Nilsson; Sweden Gothenburg Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; district heating; energy efficiency; distribution capital cost; heat demand density; plot ratio; excess heat recovery; sequential energy supply; heat utilisation rate; effective width;

    Sammanfattning : This thesis presents a set of methodologies and approaches to investigate and determine the extent by which district heating can contribute to improved energy system efficiency and reduced carbon dioxide emissions in future Europe. The main motivation for suggesting large-scale implementation of district heating as a structural energy efficiency measure to obtain these objectives originates essentially in the predicament that a majority of European buildings today remain highly dependent on fossil fuels to provide energy needed for space heating and hot water preparation. LÄS MER

  7. 5. Thermal and hydraulic performance of compact brazed plate heat exchangers operating as evaporators in domestic heat pumps

    Författare :Joachim Claesson; Björn Palm; Satish G. Kandlikar; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Applied mechanics; plate heat exchanger; evaporator; heat pump; flow boiling; pressure drop; Teknisk mekanik; Engineering mechanics; Teknisk mekanik;

    Sammanfattning : This thesis investigates the performance of compact brazed plate heat exchangers (CBE) operating as evaporator in heat pump applications. The thesis, and the performances investigated, has been divided into three main sections; One zone evaporator performance; Two zone evaporator performance; and finally Local performance. LÄS MER