Sökning: "thermal conductivity"

Visar resultat 11 - 15 av 214 uppsatser innehållade orden thermal conductivity.

1. 11. Numerical Modelling of a Packed Bed Thermal Energy Storage for Applications in a Carnot Battery : KTH Thesis Report

   Master-uppsats, KTH/Skolan för industriell teknik och management (ITM)

   Författare :Gabriel Juul; [2023]
   Nyckelord :Thermal energy storage; Carnot battery; sand; packed bed; granular medium; porous medium; effective medium technique; effective thermal conductivity; paramedic study; 3D model; COMSOL; numerical modelling; Lagring av värmeenergi; Carnot-batteri; sand; packad bädd; granulärt medium; poröst medium; effektiv mediumteknik; effektiv värmeledningsförmåga; parametrisk studie; 3D-modell; COMSOL; numerisk modellering;

   Sammanfattning : This thesis explores the heat transfer characteristics of a packed bed thermal energy storage device through the development of a 3D model in COMSOL Multiphysics. The model is based on a laboratory-scale device consisting of an aluminum box filled with sand, which acts as the thermal storage medium. LÄS MER

3. 12. The Effect on Mechanical Properties in Biochar Replaced Cement & Aggregate in Concrete Before and After Fire Exposure

   Uppsats för yrkesexamina på grundnivå, Luleå tekniska universitet/Institutionen för samhällsbyggnad och naturresurser

   Författare :Felix Hansen; Mathias Berglund; [2023]
   Nyckelord :Biochar; Concrete; Sintering; Fire; Mechanical properties; Sustainability; Cement; Biochar in concrete; Building industry; Concrete exposed to fire.; Biokol; Betong; Sintring; Eld; Mekaniska egenskaper; Hållbarhet; Cement; Biokol i betong; Byggindustri; Brandexponerad betong.;

   Sammanfattning : Concrete is good as a construction material regarding fire and its properties regarding strength. However, the concrete expands and cracks due to fire resulting in structural damage. According to the literature the concrete usually loses its strength during and after fire exposure due to themechanical and physical changes. LÄS MER

4. 13. Analysis and simultaion of underfloor heating system for bathrooms in Swedish buildings

   Magister-uppsats, Högskolan i Gävle/Energisystem och byggnadsteknik

   Författare :Andreu Fàbregas; [2023]
   Nyckelord :underfloor heating system; insulation; heating loss; energy use; building energy balance; transmission loss;

   Sammanfattning : The pursuit of reducing energy consumption and enhancing thermal efficiency across various sectors to foster sustainable practices has gained significant prominence in recent years, driven by the global environmental crisis. Sweco consultancy has undertaken a study focusing on underfloor heating systems for bathrooms in low-energy buildings located in Sweden. LÄS MER

5. 14. Application of ring statistics to characterise graphitisation of carbon fiber heat shields under atmospheric re-entry conditions

   Master-uppsats, KTH/Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik

   Författare :Hamish Keay; [2023]
   Nyckelord :Aerospace; Heat shields; Re-entry; Graphitisation; Carbon fiber; Carbon phenolic; Ring statistics; Graph theory; Molecular Dynamics; återinträde; grafitisering; kolfiber; kolfenol; ringstatistik; grafteori; molekylär dynamik;

   Sammanfattning : Carbon fibers submitted to high temperatures (>2000 °C) experience a permanent increasein their thermal conductivity. This change has been attributed to a change in the molecularstructure due to graphitisation. LÄS MER

7. 15. Hur gammal är jordens inre kärna?

   Kandidat-uppsats, Lunds universitet/Geologiska institutionen

   Författare :Tim Bergström; [2023]
   Nyckelord :Inner core; thermal conductivity; convection; Earth’s magnetic field; paleomagnetism; Earth and Environmental Sciences;

   Sammanfattning : Åldern för jordens inre kärna är en gåta som har förbryllat forskare i många decennier. Allt från en ålder lika hög som jordens magnetfält (mellan 3,5 och 4,2 Ga) i den ena änden, ner till 0,5 Ga i den andra änden. LÄS MER