Boundary Meshless Method Research Articles

A boundary meshless method with shape functions computed from the PDE

This paper presents a new meshless method using high degree polynomial shape functions. These shape functions are approximated solutions of the partial differential equation (PDE) and the discretization concerns only the boundary. If the domain is split into several subdomains, one has also to discretize the interfaces. To get a true meshless integration-free method, the boundary and interface conditions are accounted by collocation procedures. It is well known that a pure collocation technique induces numerical instabilities. That is why the collocation will be coupled with the least-squares method. The numerical technique will be applied to various second order PDE's in 2 D domains. Because there is no integration and the number of shape functions does not increase very much with the degree, high degree polynomials can be considered without a huge computational cost. As for instance the p-version of finite elements or some well established meshless methods, the present method permits to get very accurate solutions.

A boundary meshless method using Chebyshev interpolation and trigonometric basis function for solving heat conduction problems

AbstractA boundary meshless method has been developed to solve the heat conduction equations through the use of a newly established two‐stage approximation scheme and a trigonometric series expansion scheme to approximate the particular solution and fundamental solution, respectively. As a result, no fundamental solution is required and the closed form of approximate particular solution is easy to obtain. The effectiveness of the proposed computational scheme is demonstrated by several examples in 2D and 3D. We also compare our proposed method with the finite‐difference method and the other meshless method showed in Šarler and Vertnik (Comput. Math. Appl. 2006; 51:1269–1282). Excellent numerical results have been observed. Copyright © 2007 John Wiley & Sons, Ltd.

A Comparison of Point Interpolative Boundary Meshless Method Based on PBF and RBF for Transient Eddy-Current Analysis

This paper presents the boundary polynomial point interpolation meshless method (BPPIM) and the boundary radial point interpolation meshless method (BRPIM) based on the polynomial basis function (PBF) and radial basis function (RBF), respectively, for transient eddy-current analysis, and their interpolation shape functions satisfy the Kronecker delta function, thus, the essential boundary conditions can be directly imposed on the boundary nodes. An example on analyzing transient eddy current of a square metal column is set to prove the validity of the proposed methods, and a comparison on accuracy between BPPIM and BRPIM is analyzed as well

A fast multipole accelerated method of fundamental solutions for potential problems

The fast multipole method (FMM) is a very effective way to accelerate the numerical solutions of the methods based on Green's functions or fundamental solutions. Combined with the FMM, the boundary element method (BEM) can now solve large-scale problems with several million unknowns on a desktop computer. The method of fundamental solutions (MFS), also called superposition or source method and based on the fundamental solutions but without using integrals, has been studied for several decades along with the BEM. The MFS is a boundary meshless method in nature and offers more flexibility in modeling of a problem. It also avoids the singularity of the kernel by placing the source at some auxiliary points off the problem domain. However, like the traditional BEM, the conventional MFS also requires O( N 2) operations to compute the system of equations and another O( N 3) operations to solve the system using direct solvers, with N being the number of unknowns. Combining the FMM and MFS can potentially reduce the operations in formation and solution of the MFS system, as well as the memory requirement, all to O( N). This paper is an attempt in this direction. The FMM formulations for the MFS is presented for 2D potential problem. Issues in implementation of the FMM for the MFS are discussed. Numerical examples with up to 200,000 DOF's are solved successfully on a Pentium IV PC using the developed FMM MFS code. These results clearly demonstrate the efficiency, accuracy and potentials of the fast multipole accelerated MFS.

A boundary meshless method for transient eddy current problems

This paper presents a boundary meshless method (BMLM) for transient eddy current problems. With difference to the traditional boundary element method (BEM), the BMLM combines a point interpolation method (PIM) for construction of spatial interpolation functions with a boundary integral formulation for the governing equations, thus the spatial interpolation functions satisfy the Kronecker delta function and the essential boundary condition can be directly imposed without any other procedure. Theoretical analysis in details is given and a transient eddy current example is also presented to prove the proposed theory.