Improved design procedure for double-ridged waveguides

Prakash, VVS
Mittra, R
Kuzuoğlu, Mustafa
This article presents a novel methodology for designing double-ridged waveguides by numerically optimizing their geometric shape such that they sustain the two prescribed lowest order modes. The field solution to the problem is obtained by using the finite element method. The performance of the microgenetic algorithm and the quasi-Newton methods is studied for carrying out geometry optimization. This generalized formulation is capable of handling inhomogeneous material fillings in the guide, and computational results are presented to demonstrate the versatility of the proposed technique. (C) 2002 Wiley Periodicals, Inc.


Questioning Degree of Accuracy Offered by the Spectral Element Method in Computational Electromagnetics
Mahariq, I.; KURT, HAMZA; Kuzuoğlu, Mustafa (2015-07-01)
In this paper, a comparison amongst the spectral element method (SEM), the finite difference method (FDM), and the first-order finite element method (FEM) is presented. For the sake of consistency, the comparison is carried out on one-dimensional and two-dimensional boundary value problems based on the same measure of error in order to emphasize on the high accuracy gained by the SEM. Then, the deterioration in the accuracy of the SEM due to the elemental deformation is demonstrated. Following this, we try ...
Excessive Memory Usage of the ELLPACK Sparse Matrix Storage Scheme throughout the Finite Element Computations
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Sparse matrices are occasionally encountered during solution of various problems by means of numerical methods, particularly the finite element method ELLPACK sparse matrix storage scheme, one of the most widely used methods due to its implementation ease, is investigated in this study. The scheme uses excessive memory due to its definition. For the conventional finite element method, where the node elements are used, the excessive memory caused by redundant entries in the ELLPACK sparse matrix storage sche...
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Yılmaz, Ayşen; Kuzuoğlu, Mustafa (2008-01-01)
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Çınar, Okan; Erdal Erdoğmuş, Merve; Kayran, Altan; Department of Mechanical Engineering (2014)
This thesis aims to develop an alternative approach which estimates the effective elastic properties of 2D orthotropic equivalent model of the honeycomb core material. For this purpose, 3D detailed finite element (FE) model of honeycomb structure, with the actual cell geometry and the face sheets, is used as the reference structure. Effective elastic properties of the equivalent 2D orthotropic model, representing the honeycomb core, are determined by means optimization. The objective function of the optimiz...
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An approach is introduced for determining accurate two-dimensional equivalent laminated models of sandwich laminates with honeycomb core and composite facesheets by optimization involving modal behavior. The approach relies on minimizing the objective function which is defined as the sum of the square of the differences between the natural frequencies of the honeycomb sandwich laminate estimated by the finite element analysis of the 3D detailed model with the actual honeycomb core geometry and by the 2D equ...
Citation Formats
V. Prakash, R. Mittra, and M. Kuzuoğlu, “Improved design procedure for double-ridged waveguides,” INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, pp. 530–539, 2002, Accessed: 00, 2020. [Online]. Available: