Search for dissertations about: "thermal source"

Showing result 1 - 5 of 335 swedish dissertations containing the words thermal source.

2. 1. Thermal Interference Between Neighbouring Ground-Source Heat Pumps : Tools to Calcualte it and Solutions to Limit it

   Author : Maria Letizia Fascì; Joachim Claesson; Alberto Lazzarotto; Loius Lamarche; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ground source heat pumps; thermal interference; neighbouring geothermal boreholes; finite line source; mitigation strategies; Energiteknik; Energy Technology;

   Abstract : Ground Source Heat Pumps (GSHPs) have emerged as a promising technology for decarbonization of the heating sector. However, their increasing prevalence in densely populated areas may lead to considerable changes in the ground temperature, which can ultimately lead to reduced performance of the systems. READ MORE

4. 2. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes

   Author : José Acuña; Björn Palm; Jeffrey Spitler; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Borehole heat exchangers; Distributed Thermal Response Test; Ground Source Heat Pumps; Coaxial; U-pipe; Multi-pipe; Pipe-in-pipe; Multi-chamber; Groundwater; Thermosyphon; SRA - Energy; SRA - Energi;

   Abstract : U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs. READ MORE

5. 3. Thermal response test : method development and evaluation

   Author : Signhild Gehlin; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vattenteknik; Water Resources Engineering;

   Abstract : Since the first introduction of thermal response tests with mobile measurement devices in Sweden and USA in 1995, the method has developed and spread in North America and Europe. Thermal response tests have so far been used primarily for in situ determination of design data for BHE (borehole heat exchanger) systems, but also for evaluation of grout material, heat exchanger types and groundwater effects. READ MORE

6. 4. 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. 5. Mid-infrared photonic devices for on-chip optical gas sensing

   Author : Floria Ottonello Briano; Kristinn B. Gylfason; Delphine Marris-Morini; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; mid-infrared; mid-IR; photonics; silicon photonics; gas sensing; optical sensing; optical gas sensing; spectroscopy; absorption; dispersion; carbon dioxide; CO2; CO2 sensing; trace gas; ethanol sensing; alcohol sensing; waveguide; photonic waveguide; ring resonator; nanowire; nanoheater; emitter; thermal source; bolometer; microbolometer; thermal detector; high frequency; 3 omega method; plasmonic; platinum; Kanthal; silicon-on-insulator; micro-electro-mechanical systems MEMS ; microfabrication; microsystems; microtechnology; nanotechnology; Optik och fotonik; Optics and Photonics; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Gas detection is crucial in a wide range of fields and applications, such as safety and process control in the industry, atmospheric sciences, and breath diagnostics. Optical gas sensing offers some key advantages, compared to other sensing methods such as electrochemical and semiconductor sensing: high specificity, fast response, and minimal drift. READ MORE