Avancerad sökning
Visar resultat 1 - 5 av 338 avhandlingar som matchar ovanstående sökkriterier.
1. Component and system design of a mild hybrid 48 V powertrain for a light vehicle
Sammanfattning : This thesis presents contributions in three areas relevant for the development of 48 V mild hybrid electric powertrains for cars. The first part comprises methodologies and extensive testing of lithium-ion battery cells in order to establish the electric and thermal performance using equivalent circuit models. LÄS MER
2. Large-Eddy Simulation of Gasoline Fuel Spray Injection at Ultra-High Injection Pressures
Sammanfattning : Gasoline direct injection is a state-of-the-art technique that reduces hydrocarbon and particulate emissions. However, further improvement is needed to meet current as well as future emission regulations. LÄS MER
3. On the Analysis of Energy Efficient Aircraft Engines
Sammanfattning : Aero engine performance analysis is highly multidimensional using various measures of component performance such as turbomachinery and mechanical efficiencies, and pressure loss coefficients. Using conventional performance analysis, relying on only the laws of thermodynamics, it is possible to understand how the performance parameters affect the component performance, but it is difficult to directly compare the magnitude of various loss sources. LÄS MER
4. 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
5. Airborne Wind Energy - to fly or not to fly?
Sammanfattning : This thesis investigates crosswind Airborne Wind Energy Systems (AWESs) in terms of power production and potential role in future electricity generation systems. The perspective ranges from the small scale, modelling AWE as a single system, to the large, implementing AWESs in regional electricity systems. LÄS MER