Sökning: "energy level engineering"
Visar resultat 1 - 5 av 890 avhandlingar innehållade orden energy level engineering.
1. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes
Sammanfattning : 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. LÄS MER
2. Prediction horizon requirement in control and extreme load analyses for survivability : Advancements to improve the performance of wave energy technologies
Sammanfattning : The main objective of wave energy converters (WECs) is to ensure reliable electricity production at a competitive cost. Two challenges to achieving this are ensuring an efficient energy conversion and offshore survivability. LÄS MER
3. Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges
Sammanfattning : Modular battery systems based on multilevel inverter (MLI) topologies can possibly overcome some shortcomings of two-level inverters when used for vehicle propulsion. The results presented in this thesis aim to point out the advantages and disadvantages, as well as the technical challenges, of modular vehicle battery systems based on MLIs in comparison to a conventional, two-level IGBT inverter drivetrain. LÄS MER
4. On the Design Considerations for Thermal Energy Storage with Phase Change Materials: Material Characterization and Modelling
Sammanfattning : Integrating thermal energy storage (TES) technologies to a process enables storing and releasing thermal energy on demand. Depending on the implementation, this may lead to economic and ecological improvements, e.g. by shifting the peak demand to off-peak hours or by increasing the share of utilized renewable energy. LÄS MER
5. Multi-Disciplinary Conceptual Design of Future Jet Engine Systems
Sammanfattning : This thesis describes various aspects of the development of a multi-disciplinary aero engine conceptual design tool, TERA2020 (Techno-economic, Environmental and Risk Assessment for 2020), based on an explicit algorithm that considers: engine performance, engine aerodynamic and mechanical design, aircraft design and performance, emissions prediction and environmental impact, engine and airframe noise, and production, maintenance and direct operating costs.As part of this research effort, a newly-derived semi-empirical NOx correlation for modern rich-burn single-annular combustors is proposed. LÄS MER