Ola Ragb¹, Mokhtar Mohamed², Mohamed S. Matbuly¹, Omer Civalek^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.3, pp. 2193-2217, 2023, DOI:10.32604/cmes.2023.028992

Abstract Four numerical schemes are introduced for the analysis of photocurrent transients in organic photovoltaic devices. The mathematical model for organic polymer solar cells contains a nonlinear diffusion–reaction partial differential equation system with electrostatic convection attached to a kinetic ordinary differential equation. To solve the problem, Polynomial-based differential quadrature, Sinc, and Discrete singular convolution are combined with block marching techniques. These schemes are employed to reduce the problem to a nonlinear algebraic system. The iterative quadrature technique is used to solve the reduced problem. The obtained results agreed with the previous exact one and the finite element method. Further, the effects… More > Graphic Abstract

Ali Kemal Baltacıoğlu¹, Ömer Civalek^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.68, No.1, pp. 1-24, 2010, DOI:10.3970/cmes.2010.068.001

Abstract Geometrically nonlinear static analysis of an anisotropic thick plate resting on nonlinear two-parameter elastic foundations has been studied. The plate formulation is based on first-order shear deformation theory (FSDT). The governing equation of bending for rectangular orthotropic thick plate is derived by using von Karman equation. The nonlinear static deflections of orthotropic plates on elastic foundation are investigated using the discrete singular convolution method. The effects of foundation, material and geometric parameters of orthotropic plates on nonlinear deflections are investigated. More >

Ömer Civalek ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.31, No.1, pp. 25-36, 2008, DOI:10.3970/cmes.2008.031.025

Abstract In this paper, free vibration analysis of curvilinear or straight-sided quadrilateral membranes is presented. In the proposed approach, irregular physical domain is transformed into a rectangular domain by using geometric coordinate transformation. For demonstration of the accuracy and convergence of the method, some numerical examples are provided on membranes with different geometry such as skew, trapezoidal, sectorial, annular sectorial, and membranes with four curved edges. The results obtained by the DSC method are compared with those obtained by other numerical and analytical methods. More >