Sökning: "Harmonic expansion"
Visar resultat 1 - 5 av 15 avhandlingar innehållade orden Harmonic expansion.
1. Modelling tools for quieter vehicles : Waves in poro– and visco–elastic continua
Sammanfattning : New modelling tools intended to contribute to the development of components for quieter vehicles are developed. The tools are based on continuum models for wave propagation in poro– and visco–elastic media. By using geometric attributes of the studied components, the computational cost may be radically decreased compared to traditional methods. LÄS MER
2. Computational investigation of interface structure and composition in cemented carbides at finite temperatures
Sammanfattning : WC-Co cemented carbides combine superb hardness with high toughness making them ideal for usage in high-speed machining of steels and in wear resistance tools. These excellent mechanical properties are to a large extent dependent on the microstructure and thus the interfacial properties of the material. LÄS MER
3. Dynamic analyses of structures with applied rubber
Sammanfattning : The aim with the present thesis has been to develop efficient, practical and accuratemethods in order to model rubber in dynamic analyses, with emphasis on passive constrainedlayer damping materials. A fractional order viscoelastic constitutive model ismapped onto experimental data from a measurement standard using a vibrating beamtechnique. LÄS MER
4. Managing uncertainties through efficient calculation of transients and harmonic propagation in power systems
Sammanfattning : The electric power system is undergoing changes including large-scale introduction of renewable energy sources together with HVDC/FACTS, changes in the network such as increased amount of high voltage cables, industrial electrification, and changes in the load composition. These changes will impact the system in different ways and lead to challenges that must be addressed to facilitate planning, dimensioning, and operation of the system in a secure and economical way. LÄS MER
5. Creep modeling and first-principles investigation of high-temperature alloys
Sammanfattning : Stainless steels and nickel-based superalloys are materials that have been widely used to manufacture components servicing at high temperatures. Creep strength is one of the most important properties in such conditions. LÄS MER