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Visar resultat 1 - 5 av 173 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Experimentella studier av värmeflöden och värmelagring i ett bebott flerbostadshus

   Författare :Lars Stenlund; Gunnar Bäckström; Olov Sandberg; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Energy balance; heat storage; heat flow; night setback; buildings; time constants;

   Sammanfattning : The study is experimentally inclined, with a high target precision for performance measurement. A comprehensive programme of measurements was carried out in a two-storey building, having a massive structure and dating from 1970. Measurements were made continuously during the heating season from a total of about 70 points. LÄS MER

3. 2. Balancing variable renewable electricity generation using combined heat and power plants, large-scale heat pumps, and thermal energy storages in Swedish district heating systems

   Författare :Svante Monie; Magnus Åberg; Annica Nilsson; Joakim Widén; Magnus Wallén; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; District heating systems; Power-to-Heat; Heat pumps; Combined heat and power; Thermal energy storage; Power balance; Variable renewable electricity; Biomass fuel; Engineering Science with specialization in Civil Engineering and Built Environment; Teknisk fysik med inriktning mot byggteknik och byggd miljö;

   Sammanfattning : The global ambitions to hamper the greenhouse effect has led to ambitious targets for increasing renewable energy use. This, in combination with recent years' vast development of wind and solar power, implies that there will be significant amounts of variable renewable electricity (VRE) in future energy systems. LÄS MER

4. 3. Heat Balance Modeling of a Stationary Fluidized-Bed Furnace Burning Biomass

   Författare :Fredrik Niklasson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mixing; modeling; biomass; dispersion; heat balance; fluidized bed boiler;

   Sammanfattning : The influence of biomass fuel properties on the heat balance of the bottom region (bed and splash zone) of a commercial-scale bubbling fluidized-bed furnace is investigated theoretically and experimentally. The experiments have been carried out at the Chalmers 12 MWth research boiler, operated under non-circulating conditions during most of the experiments. LÄS MER

5. 4. Boreal land surface water and heat balance : Modelling soil-snow-vegetation-atmosphere behaviour

   Författare :David Gustafsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; soil; snow; land surface heat exchange; forest; arable land; eddy-correlation; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

   Sammanfattning : The water and heat exchange in thesoil-snow-vegetation-atmosphere system was studied in order toimprove the quantitative knowledge of land surface processes.In this study, numerical simulation models and availabledatasets representing arable land, sub-alpine snowpack, andboreal forest were evaluated at both diurnal and seasonaltimescales. LÄS MER

7. 5. Land surface heat exchange over snow and frozen soil

   Författare :David Gustafsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Surface energy balance; Snow; Boreal forest; SVAT models; Eddy-correlation Measurements; Latent heat flux; Sensible heat flux; Net radiation; Soil temperature; Aerodynamic roughness; Surface resistance; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

   Sammanfattning : The energy exchange in the soil-snow-vegetation-atmospheresystem was studied to improve the quantitative knowledge of thegoverning processes. The lack of such knowledge contributes tothe uncertainty in the applicability of many existing modelsindependent of the temporal or spatial scale. LÄS MER