Finite element modeling of scattering from objects in rectangular waveguides

Gülbaş, Hüseyin
Numerical analysis of scattering parameters of split ring resonators which are one of the microwave circuit elements is performed by the Finite Element Method in this thesis. The fundamentals of the model and analysis method will be discussed firstly. Afterwards, the basics of Finite Element Method including weak variational form of the wave equation, 3D formulations and application to scattering parameters will be presented. The concepts of Perfectly Matched Layer and resonators will be examined in detail. The accuracy of the method will be tested and the effects of different design parameters on the scattering parameters of split ring resonators will be investigated. These design parameters will be slit width, side width, and operation frequency. Moreover, reflection and transmission from the dielectric surfaces will be discussed. Additionally, each result will be compared with the ones achieved by using CST (Computer Simulation Technology) simulation software. 


Finite Element Domain Decomposition Method for Rough Sea Surface Scattering
ÖZGÜN, ÖZLEM; Kuzuoğlu, Mustafa (2019-12-31)
Full-wave solution of electromagnetic wave scattering from rough sea surfaces is achieved by the Finite Element Domain Decomposition (FEDD) method. The method is implemented in a non-iterative manner by dividing the computational domain into overlapping subdomains, and solving the problem in each subdomain by attaching Locally-Conformal Perfectly Matched Layer (LC-PML) at the truncation boundaries. Statistical behavior of the Radar Cross Section (RCS) is investigated by Monte Carlo simulations. The results ...
Finite element study of biomagnetic fluid flow in a symmetrically stenosed channel
Turk, O.; Tezer, Münevver; Bozkaya, Canan (Elsevier BV, 2014-03-15)
The two-dimensional unsteady, laminar flow of a viscous, Newtonian, incompressible and electrically conducting biofluid in a channel with a stenosis, under the influence of a spatially varying magnetic field, is considered. The mathematical modeling of the problem results in a coupled nonlinear system of equations and is given in stream function-vorticity-temperature formulation for the numerical treatment. These equations together with their appropriate boundary conditions are solved iteratively using the ...
Investigation of rough surface scattering of electromagnetic waves using finite element method
Aşırım, Özüm Emre; Kuzuoğlu, Mustafa; Özgün, Özlem; Department of Electrical and Electronics Engineering (2013)
This thesis analyzes the problem of electromagnetic wave scattering from rough surfaces using finite element method. Concepts like mesh generation and random rough surface generation will be discussed firstly. Then the fundamental concepts of the finite element method which are the functional form of a given partial differential equation, implementation of the element coefficient matrices, and the assemblage of elements will be discussed in detail. The rough surface and the overall mesh geometry will be imp...
Finite element analysis of a projection-based stabilization method for the Darcy-Brinkman equations in double-diffusive convection
Cibik, Aytekin; Kaya Merdan, Songül (2013-02-01)
This paper presents a projection-based stabilization method of the double-diffusive convection in Darcy-Brinkman flow. In particular, it is concerned with the convergence analysis of the velocity, temperature and concentration in the time dependent case. Numerical experiments are presented to verify both the theory and the effectiveness of the method. (C) 2012 IMACS. Published by Elsevier B.V. All rights reserved.
Finite element method solution of electrically driven magnetohydrodynamic flow
Nesliturk, AI; Tezer, Münevver (Elsevier BV, 2006-08-01)
The magnetohydrodynamic (MHD) flow in a rectangular duct is investigated for the case when the flow is driven by the current produced by electrodes, placed one in each of the walls of the duct where the applied magnetic field is perpendicular, The flow is steady, laminar and the fluid is incompressible, viscous and electrically conducting. A stabilized finite element with the residual-free bubble (RFB) functions is used for solving the governing equations. The finite element method employing the RFB functio...
Citation Formats
H. Gülbaş, “Finite element modeling of scattering from objects in rectangular waveguides,” M.S. - Master of Science, Middle East Technical University, 2017.