Search for dissertations about: "insulation capacity"

Showing result 1 - 5 of 24 swedish dissertations containing the words insulation capacity.

  2. 1. Predicting the Long-Term Insulation Performance of District Heating Pipes

    Author : Camilla Persson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat conduction; polyurethane foam; insulation capacity; diffusion; thermal conductivity; cyclopentane; solubility coefficient; long-term performance;

    Abstract : The aim of the studies that comprise this thesis was to predict the heat loss over timefrom a range of district heating pipes insulated with closed-cells foam. The thermalconductivity of the foam changes over time when it is not diffusion-tight encapsulatedagainst the environment, as diffusion alters the cell gas composition until it reachesequilibrium with the surrounding air. READ MORE

  4. 2. Environmental and Thermal Performance of District Heating Pipes

    Author : Morgan Fröling; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; district heat distribution; cyclopentane; district heating pipe; long-term thermal performance; life cycle assessment; insulation; polyurethane foam; environmental performance; carbon dioxide; HFC-365mfc;

    Abstract : In order to move towards a sustainable society we need to increase the efficiency of our use of available resources, not only in economic terms but also in ecological terms. District heating, the utilisation of centrally produced heat for space heating and domestic hot water generation, has the potential to contribute to the eco-efficient use of energy resources in the parts of the world where space heating is needed. READ MORE

  5. 3. Polyethylene – metal oxide particle nanocomposites for future HVDC cable insulation : From interface tailoring to designed performance

    Author : Dongming Liu; Ulf Gedde; Mikael Hedenqvist; Richard Olsson; Linda Schadler; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; electrical insulation; core-shell nanoparticles; surface modification; silane chemistry; nanocomposites; polyethylene; adsorption; long-term stability; interface; particle dispersion; cavitation; conductivity; HVDC; elektrisk isolation; ytmodifiering; silankemi; nanokompositer; polyeten; adsorption; långtidsstabilitet; ytskikt; partikeldispergering; kavitation; ledningsförmåga; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : Low-density polyethylene (LDPE) nanocomposites containing metal oxide nanoparticles are considered as promising candidates for insulating materials in future high-voltage direct-current (HVDC) cables. The significant improvement in dielectric properties compared with unfilled polymer is attributed to the large and active interface between the nanoparticles and the polymer. READ MORE

  6. 4. Blowing Agents in Rigid Polyurethane Foam - Analytical Studies - Technical and Environmental Aspects

    Author : Magdalena Svanström; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; insulation; ageing; district heating pipes; cyclopentane; CFC-11; carbon dioxide; diffusion; blowing agents; polyurethane foam;

    Abstract : Rigid polyurethane foam is used in many different applications because of its high insulating capacity. CFC-11 has been the predominant blowing agent due to its advantageous properties, especially its low thermal conductivity. READ MORE

  7. 5. Condensation and frost formation in fibrous thermal-insulation materials

    Author : Tomáš Vrána; Folke Björk; Ove Söderström; Kjartan Gudmundsson; Carsten Rode; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fibrous thermal insulation; Stone wool; Cellulose; MAterial properties; Moisture transport; Condensation; Frost formation; Exterior conditions; Interior conditions; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur; Construction materials; Konstruktionsmaterial;

    Abstract : Heavily insulated constructions are at present being used to strike at the vast energy consumption in residential buildings and commercial alike. They introduce a high-thickness layer of thermal insulation in the building envelopes. READ MORE