Sökning: "self-sustained oscillations"
Hittade 5 avhandlingar innehållade orden self-sustained oscillations.
1. Aeroacoustics Studies of Duct Branches with Application to Silencers
Sammanfattning : New methodologies and concepts for developing compact and energy efficient automotive exhaust systems have been studied. This originates in the growing concern for global warming, to which road transportation is a major contributor. LÄS MER
2. Fighting flameless fires : Initiating and extinguishing self-sustainedsmoldering fires in wood pellets
Sammanfattning : Smoldering fires represent domestic, environmental and industrial hazards. This flameless form of combustion is more easily initiated than flaming, and is also more persistent and difficult to extinguish. The growing demand for non-fossil fuels has increased the use of solid biofuels such as biomass. LÄS MER
3. Analysis and control of transitional shear flows using global modes
Sammanfattning : In this thesis direct numerical simulations are used to investigate two phenomenain shear flows: laminar-turbulent transition over a flat plate and periodicvortex shedding induced by a jet in cross flow. The emphasis is on understanding and controlling the flow dynamics using tools from dynamical systems and control theory. LÄS MER
4. Oscillatory phenomena in chloroplasts from spinach cotyledons
Sammanfattning : A suspensionofchloroplasts, isolated from spinach cotyledons, was found to be an oscillatory system, i.e. a system in which one parameter (or more) varies over time in a fairly regular way.The oscillations, with a period of fifteen to twenty minutes,occured spontaneously in the light as well as in the dark and were self-sustained for several hours. LÄS MER
5. Electronic Control of Flexural Nanowire Vibrations
Sammanfattning : “Nanoelectromechanical systems” (NEMS) are nanometer-sized mechanical structures coupled to electronic devices of comparable size. The coupling between mechanical and electronic degrees of freedom, combined with their mesoscopic size, provide these systemswith some unique properties that make them interesting from both the fundamental and technological point of view. LÄS MER