Sökning: "Floquet analysis"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Floquet analysis.

  1. 1. Analysis of Conformal Antennas and Periodic Structures

    Författare :Silvia Raffaelli; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; method of moments; microstrip; corrugated surface; horn; Floquet; array; periodic; multilayer structure; finite difference time domain; dual-frequency; infinite; spectral domain analysis; conformal antenna;

    Sammanfattning : In the last decades much attention has been paid to the design of high-performance antennas. Accurate control of the radiation properties is very important in electromagnetic engineering applications. LÄS MER

  3. 2. Periodic Structures with Higher Symmetries: Analysis and Applications

    Författare :Fatemeh Ghasemifard; Martin Norgren; Oscar Quevedo-Teruel; Guido Valerio; Stefano Maci; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; periodic structures; higher symmetries; dispersion analysis; mode matching; generalized Floquet theorem; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In this thesis, periodic structures with higher symmetries are studied. Their wave propagation characteristics are investigated and their potential applications are discussed. Higher-symmetric periodic structures are described with an additional geometrical operation beyond a translation operator. LÄS MER

  4. 3. Linear and non-linear dynamics of non-autonomous flows

    Författare :J. Simon Kern; Dan S. Henningson; Ardeshir Hanifi; Peter J. Schmid; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time-dependent flows; linear stability; non-linear dynamics; Floquet analysis; optimally time-dependent modes; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Fluid flows subject to time-dependent external forces or boundary conditions are ubiquitous in biology and technical applications. Whether one considers birds flying by flapping their wings or the gust response of wind turbines, the flow is non-autonomous. LÄS MER

  5. 4. Stability of statically and periodically loaded structures

    Författare :Ingrid Svensson; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulics; Mechanical engineering; Produktionsteknik; Production technology; experiments; damping; impacts; branch switching; dynamic stability; deflation; path following; vibrationer; akustik; vakuumteknik; hydraulik; Maskinteknik; vibration and acoustic engineering; vacuum technology;

    Sammanfattning : In this thesis different kinds of stability phenomena are analysed. Firstly the quasi-static behaviour of an elastic structure is studied for increasing loading. LÄS MER

  7. 5. Shapes of pipes

    Författare :Valerio Lupi; Philipp Schlatter; Ramis Örlü; Jean-Christophe Robinet; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Global stability; curved pipes; secondary flow; wall-bounded turbulence; Global stabilitet; krökta rör; sekundärflöde; turbulens; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : Curved pipes are ubiquitous in several industrial applications and biological systems. The study of flows through these configurations is therefore of significant practical interest.In the present thesis, the modal stability of flows in both toroidal and spatially developing bent pipes is investigated to understand the onset of transition. LÄS MER