Papers by Keyword: Boundary Integral Equations

Abstract: In order to improve the efficient and accuracy, parallel algorithm of fast multipole boundary element method (FM-BEM) was presented. Combined with sparse approximate inverse preconditioning (SPAI), GMRES(m) was used to solve the equation system of FM-BEM. The parallel FM-BEM was applied to strip cold rolling process, the results obtained from parallel FM-BEM was similar with the experimental measurements. The parallel FM-BEM has more efficient and accuracy than traditional FM-BEM. This method is benefit for solving precision engineering problem.

Abstract: The occurrence of small scale plasticity can be modeled physically by force doublets embedded in an elastic medium and therefore the plasticity problem can be treated by the superposition of elastic solutions. This idea for the treatment of an inelastic strain is reviewed and generalized to develop a versatile program for two-dimensional elastic-plastic problems based on Body Force Method. In the present study, a treatment of an elastic-perfect plastic body is discussed in detail. The increment of the density of force doublets, which has one to one correspondence to the increment of plastic strain, can be determined from Prandtl-Reuss equation. It was also found the Delaunay triangulation is useful and convenient for the automated elastic-plastic analysis.

Abstract: This work aims at introducing the concept of the numerical Green’s function (NGF) idea for elastostatic fracture mechanics using the boundary element-free method (BEFM). Unlike the local boundary integral equation method (LBIE), the BEFM only requires boundary interpolation. This method derives from the coupling of the boundary integral equation method and the orthogonal moving least-squares approximation scheme (OMLS). OMLS differs from standard MLS by using an orthogonal basis instead of only a linear independent one, which increases its accuracy and efficiency. Some illustrative examples are included in the end.

Abstract: This paper concerns fracture dynamic problems for elastic cracked solids with allowance for crack faces contact interaction. The contact problem for a penny-shaped crack with an initial opening under normally incident tension-compression wave is solved by the method of boundary integral equations. The solution is compared with those obtained without allowance for crack faces contact interaction for various values of the initial opening.

Abstract: A novel integral equation method is developed in this paper for the analysis of two-dimensional general piezoelectric cracked bodies. In contrast to the conventional boundary integral methods based on reciprocal work theorem, the present method is derived from Stroh’s formalism for anisotropic elasticity in conjunction with Cauchy’s integral formula. The proposed boundary integral equations contain generalized boundary displacement (displacements and electric potential) gradients and generalized tractions (tractions and electric displacement) on the non-crack boundary, and the generalized dislocations on the crack lines. The boundary integral equations can be solved using Gaussian-type integration formulas without dividing the boundary into discrete elements. The crack-tip singularity is explicitly incorporated and the generalized intensity factors can be computed directly. Numerical examples of generalized stress intensity factors are given to illustrate the effectiveness and accuracy of the present method.