Search for dissertations about: "thermo-physical properties"

Showing result 11 - 15 of 19 swedish dissertations containing the words thermo-physical properties.

2. 11. Rock Mechanical Consequences of Refrigeration. A Study Based on a Pilot Scale Rock Cavern

   Author : Lars-Olof Dahlström; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; temperature decrease; tensile strength; thermomechanical loading; compressive strength; Poisson s ratio; thermal contraction; rock caverns; rock mass deformation; Young s modulus;

   Abstract : The deformation of a rock mass due to temperature decrease below freezing is very complex, since many factors are involved; thermal strain, strain due to stress change, stress re-distribution, ice formation and the temperature dependency of rock mechanical and thermo-physical properties. The objective of this study was to achieve a better understanding of the rock mass response to thermo-mechanical loading when storing low temperature products in rock caverns excavated in hard crystalline rock masses. READ MORE

4. 12. Measurements and Modelling of Convective Vaporization for Refrigerants in a Horizontal Tube

   Author : Peter Melin; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; n-butane; HFC134a; pressure drop; propane; HFC143a; horizontal flow boiling; in-tube vaporization; HFC125; HFC32; experimental study; HCFC142b; HCFC22; non-azeotropic mixtures; CFC12; modelling; mixture effects;

   Abstract : An evaporator facility has been constructed to measure local values of heat transfer and pressure drop. The evaporator resembles a normal working evaporator tube in a direct-expansion evaporator applicable to large heat pump/refrigeration cycles, typically over 500 kW. The evaporator is brine-heated and uses an expansion valve to control the inlet. READ MORE

5. 13. CO2 Separation with Ionic Liquids -Property, Gas solubility and Energy consumption

   Author : Yujiao Xie; Päivi Elisa Mäki-Arvela; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

   Abstract : Ionic liquids (ILs) have shown great potential to be used as liquid absorbents for CO2 capture because of its advantages, such as non-volatility, functionality, high CO2 solubility and lower energy requirements for regeneration. A significant amount of research has been carried out, but most of them are on the synthesis of novel ILs and the measurements of CO2 solubility in ILs. READ MORE

6. 14. Thermally Conductive High-Density Polyethylene Composites for Ground Heat Exchangers

   Author : Adib Kalantar Mehrjerdi; Högskolan i Borås; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-density polyethylene; talc; thermal conductivity; thermal diffusivity; thermal stability; melt rheology; oxidation induction time; α relaxation; strain hardening;

   Abstract : Today, the energy used for the heating and cooling of offices, shopping centres, schools, residential areas, andother buildings is as large as 50% of the total energy consumption in the world. The climate change, globalwarming, and environmental issues have forced high requirements for energy efficiency and clean energyproduction in buildings. READ MORE

7. 15. Biodiesel Spray Combustion Modeling Based on a Detailed Chemistry Approach

   Author : Junfeng Yang; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reduction and Validation; Spray Characteristics; Detailed Chemistry; Biodiesel;

   Abstract : Replacing conventional diesel fuels with biodiesel has the potential to drastically reduce engine-out emissions of soot, carbon monoxide, and total unburnt hydrocarbons, at the cost of slightly increased nitrogen oxide emissions. However, to realize the full benefits of using biofuels in this way, there is a need for theoretical models describing their combustion in internal combustion engines. READ MORE