Search for dissertations about: "cavity method"

Showing result 1 - 5 of 140 swedish dissertations containing the words cavity method.

  1. 1. Moment Method Analysis of Antennas in Reverberation Chambers and Cylindrical Structures

    Author : Ulf Carlberg; [2006]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna; spectral domain method; reverberation chamber; Ewald summation; moment method; cavity; cylindrical structure; Green s function; absorption cross section;

    Abstract : This thesis is a collection of papers using the method of moments for numerical analysis. The papers can be divided into two main groups; a study of antennas in reverberation chambers and a study of antennas in cylindrical structures.The reverberation chamber is a metal cavity for measuring antennas and other devices. READ MORE

  2. 2. Moment Method Analysis of Antennas in Reverberation Chambers and Cylindrical Structures

    Author : Ulf Carlberg; [2004]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cavity; spectral domain method; cylindrical structure; Ewald summation; Green s function; absorption cross section; moment method; reverberation chamber; antenna;

    Abstract : This thesis is a collection of papers using the method of moments for numerical analysis. The papers can be divided into two main groups; a study of antennas in reverberationchambers, and a study of antennas in cylindrical structures.The reverberation chamber is a metal cavity for measuring antennas and other devices. READ MORE

  3. 3. Dispersion Engineering Negative Refraction and Designed Surface Plasmons in Periodic Structures

    University dissertation from Stockholm : KTH

    Author : Zhichao Ruan; KTH.; [2007]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photonic crystal; dispersion property; negative refraction; surface plasmon polariton; designed surface plasmon; negative index material; layer-KKR method; finite-difference time-domain method; plane wave method; subwavelength imaging; open cavity; enhanced transmission; slowing light; TECHNOLOGY Electrical engineering; electronics and photonics Photonics; TEKNIKVETENSKAP Elektroteknik; elektronik och fotonik Fotonik;

    Abstract : The dispersion property of periodic structures is a hot research topic in the last decade. By exploiting dispersion properties, one can manipulate the propagation of electromagnetic waves, and produce effects that do not exist in conventional materials. READ MORE

  4. 4. Aspects of adaptive mesh refinement in the spectral element method

    University dissertation from KTH Royal Institute of Technology

    Author : Nicolas Offermans; KTH.; [2019]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Error estimators; mesh refinement; adaptivity; spectral element method; algebraic multigrid method; NACA4412; periodic hill case.; Teknisk mekanik; Engineering Mechanics;

    Abstract : This thesis deals with the improvement of the efficiency of numerical simulations in computational fluid dynamics. Some of the limitations of current algorithms on future exascale supercomputers are addressed with the main goal of using adaptive mesh refinement for the simulation of turbulent and three-dimensional flows. READ MORE

  5. 5. Studies on instability and optimal forcing of incompressible flows

    University dissertation from Stockholm, Sweden : KTH Royal Institute of Technology

    Author : Mattias Brynjell-Rahkola; KTH.; KTH.; KTH.; [2017]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydrodynamic stability; optimal forcing; resolvent operator; Laplace preconditioner; spectral element method; eigenvalue problems; inverse power method; direct numerical simulations; Falkner–Skan–Cooke boundary layer; localized roughness; crossflow vortices; Blasius boundary layer; localized suction; helical vortices; lid-driven cavity; cylinder flow; Teknisk mekanik; Engineering Mechanics;

    Abstract : This thesis considers the hydrodynamic instability and optimal forcing of a number of incompressible flow cases. In the first part, the instabilities of three problems that are of great interest in energy and aerospace applications are studied, namely a Blasius boundary layer subject to localized wall-suction, a Falkner–Skan–Cooke boundary layer with a localized surface roughness, and a pair of helical vortices. READ MORE