Solution of the nonlinear diffusion equation using the dual reciprocity boundary element method and the relaxation type time integration scheme

2005-03-18
Meral, G
We present the combined application of the dual reciprocity boundary element method (DRBEM) and the finite difference method (FDM) with a relaxation parameter to the nonlinear diffusion equation: partial derivative u/partial derivative t = V del(2)u + p(u) at where p(u) is the nonlinear term. The DRBEM is employed to discretize the spatial partial derivatives by using the fundamental solution of the Laplace operator, keeping the time derivative and the nonlinearity as the nonhomogeneous terms in the equation. The resulting system of ordinary differential equations is solved using the FDM with a relaxation procedure. A relaxation parameter is used to position the solution from the two time levels aiming to increase the convergence rate with a moderate time step to the steady state and also to obtain a stable solution. The nonlinear terms do not present problems since they are treated as the nonhomogeneity of the diffusion equation with the help of the DRBEM. The solution procedure described here is also applicable to the diffusion and convection-diffusion equation and can be considered as the extension to the nonlinear reaction-diffusion equation. Numerical experiments are given to illustrate this scheme and to compare its performance with the other numerical schemes as well as the exact solution whenever it is available. The solution agrees very well with the exact solution while some other numerical schemes may result with some unwanted oscillations in the computed solution. The optimal value of the relaxation parameter is obtained numerically for preventing use of very small time increments and to achieve a stable solution. The DRBEM with a relaxation type time integration scheme exhibits a superior accuracy at large time values for the problems tending towards a steady state.
27th World Conference on Boundary Elements and Other Mesh Reduction Methods

Suggestions

Solution of Navier-Stokes Equations Using FEM with Stabilizing Subgrid
Tezer, Münevver; Aydın Bayram, Selma (2009-07-03)
The Galerkin finite element method (FEM) is used for solving the incompressible Navier Stokes equations in 2D. Regular triangular elements are used to discretize the domain and the finite-dimensional spaces employed consist of piece wise continuous linear interpolants enriched with the residual-free bubble (RFB) functions. To find the bubble part of the solution, a two-level FEM with a stabilizing subgrid of a single node is described in our previous paper [Int. J. Numer. Methods Fluids 58, 551-572 (2007)]....
Least squares differential quadrature time integration scheme in the dual reciprocity boundary element method solution of convection-diffusion problems
Bozkaya, Canan (2005-03-18)
The least squares differential quadrature method (DQM) is used for solving the ordinary differential equations in time, obtained from the application of the dual reciprocity boundary element method (DRBEM) for the spatial partial derivatives in convection-diffusion type problems. The DRBEM enables us to use the fundamental solution of the Laplace equation which is easy to implement computationally. The time derivative and the convection terms are considered as the nonhomogeneity in the equation which are ap...
Solution to transient Navier-Stokes equations by the coupling of differential quadrature time integration scheme with dual reciprocity boundary element method
Bozkaya, Canan; Tezer, Münevver (Wiley, 2009-01-20)
The two-dimensional time-dependent Navier-Stokes equations in terms of the vorticity and the stream function are solved numerically by using the coupling of the dual reciprocity boundary element method (DRBEM) in space with the differential quadrature method (DQM) in time. In DRBEM application, the convective and the time derivative terms in the vorticity transport equation are considered as the nonhomogeneity in the equation and are approximated by radial basis functions. The solution to the Poisson equati...
Solutions of the spatially-dependent mass Dirac equation with the spin and pseudospin symmetry for the Coulomb-like potential
IKHDAİR, SAMEER; Sever, Ramazan (2010-03-15)
We study the effect of spatially-dependent mass function over the solution of the Dirac equation with the Coulomb potential in the (3 + 1)-dimensions for any arbitrary spin-orbit kappa state. In the framework of the spin and pseudospin symmetry concept, the analytic bound state energy eigenvalues and the corresponding upper and lower two-component spinors of the two Dirac particles are obtained by means of the Nikiforov-Uvarov method, in closed form. This physical choice of the mass function leads to an exa...
Dual reciprocity boundary element method for magnetohydrodynamic flow using radial basis functions
Tezer, Münevver (2002-02-01)
A dual reciprocity boundary element method is given to obtain the solution in terms of velocity and induced magnetic field for the study of MHD (magnetohydrodynamic) flow through a rectangular duct having insulating walls. The equations are transformed to two types of nonlinear Poisson equations and the right-hand sides in these equations are approximated using combinations of two classes of radial basis functions (the value of the function and its normal derivatives are utilized for approximation). Computa...
Citation Formats
G. Meral, “Solution of the nonlinear diffusion equation using the dual reciprocity boundary element method and the relaxation type time integration scheme,” Orlando, FL, 2005, vol. 39, p. 133, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/63385.