Sökning: "Plane wave expansion method"

Visar resultat 6 - 10 av 10 avhandlingar innehållade orden Plane wave expansion method.

  1. 6. Ways of determining and characterising resonances in scattering processes

    Författare :Ksenia Shilyaeva; Nils Elander; Dage Sundholm; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum scattering theory; complex scaling; resonances; Molecular physics; Molekylfysik; fysik; Physics;

    Sammanfattning : Scattering cross sections very often display structures. To clarify if these structures correspond to resonances one has to check if they are poles of the scattering matrix (S-matrix) in the fourth quadrant of the complex momentum plane. Furthermore, the states corresponding to these poles also need to have an appropriate scattering amplitude. LÄS MER

  3. 7. Modelling of ultrasonic testing for cracks near a non-planar surface

    Författare :Jonathan Westlund; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultrasonics; BIEM; Elastic waves; Nondestructive testing; Crack; BEM.;

    Sammanfattning : Nondestructive testing using ultrasound has important applications in e.g. the nuclear power and aerospace industries, where it is used to inspect safety-critical parts for flaws. LÄS MER

  4. 8. Acoustic scattering in ducts and influence of flow coupling

    Författare :Susann Boij; KTH; []
    Nyckelord :sound; vortex sheet; flow separation; end correction; Strouhal number; non-orthogonal modes; energy balance; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : The subject of this thesis is the acoustic properties offlow duct area expansions and the influence of flow-acousticcoupling at sharp edges. For low Mach number flow, significantinteraction between the sound field and the flow field canoccur at such points of flow separation. LÄS MER

  5. 9. On the ECO2 multifunctional design paradigm and tools for acoustic tailoring

    Författare :Juan Pablo Parra Martinez; Peter Göransson; Olivier Dazel; Jacques Cuenca; Per Wennhage; Franck Sgard; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vehicle design; planned obsolescence; anisotropy; porous materials; sound absorbing materials; acoustic modelling; power balance; energy assessment; dissipated power.; Farkostteknik; Vehicle and Maritime Engineering;

    Sammanfattning : Nowadays vehicle design paradigm influences not only the effectiveness of the different means of transport, but also the environment and economy in a critical way. The assessment of the consequences that design choices have on society at large are necessary to understand the limits of the methods and techniques currently employed. LÄS MER

  7. 10. A measurement approach to determination of coating thickness with eddy currents and to a capacitive person detector for robot safety

    Författare :Lennart Båvall; Keijo Nikoskinen; Linköpings universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : The research presented in this thesis is about coating thickness measurements using eddy currents, and a capacitive detector for detecting humans, for safety in industry.A method for determination of coating thickness of a copper-plated steel wire by measurement of the internal wire impedance, when this is forced by a constant, sinusoidal current, is presented. LÄS MER