In this paper, the boundary element method is applied to investigate the internal state of stress of autofretted tube with notch and the calculated results are important in the practical design.
There is a common difficulty in elastic-plastic impact codes such as EPIC[2,3] NONSAP[4], etc.. Most of these codes use the simple linear functions usually taken from static problem to represent the displacement compo...There is a common difficulty in elastic-plastic impact codes such as EPIC[2,3] NONSAP[4], etc.. Most of these codes use the simple linear functions usually taken from static problem to represent the displacement components. In such finite element formulation, the stress components are constant in each element and they are discontinuous in any two neighboring elements. Therefore, the bases of using the virtual work principle in such elements are unreliable. In this paper, we introduce a new method, namely, the compatible stress iterative method, to eliminate the above-said difficulty. The calculated examples show that the calculation using the new method in dynamic finite element analysis of high velocity impact is valid and stable, and the element stiffness can be somewhat reduced.展开更多
In paper [5], we proposed the boundary expanding-contracting principle and the boundary expanding-contracting method (BECM). In this paper we make some complemental statements and detailed proofs about the principle.
The boundary element method (KEM) which a used to solve the elastic problems has more advantages than other numerical methods. Especially, it can resolve rapidly varying internal stress and strain fields more accurate...The boundary element method (KEM) which a used to solve the elastic problems has more advantages than other numerical methods. Especially, it can resolve rapidly varying internal stress and strain fields more accurately. However, it is of en fails in the region near the boundary because of the singularity of the solutions. Though we can increase the boundary meshes more and more, the solutions of stress on the boundary can't be given directly; which has obstructed the applications of the HEM to some extent.In this paper we proposed the boudary expanding-contracting principle and the boundary expanding-contracting method (BECM) based on the principle. With this method, not only the solutions in the region near or on the boundary can be obtained directly, but the iterative processes can also he used conveniently to improve the accuracy of the solutions.展开更多
文摘In this paper, the boundary element method is applied to investigate the internal state of stress of autofretted tube with notch and the calculated results are important in the practical design.
文摘There is a common difficulty in elastic-plastic impact codes such as EPIC[2,3] NONSAP[4], etc.. Most of these codes use the simple linear functions usually taken from static problem to represent the displacement components. In such finite element formulation, the stress components are constant in each element and they are discontinuous in any two neighboring elements. Therefore, the bases of using the virtual work principle in such elements are unreliable. In this paper, we introduce a new method, namely, the compatible stress iterative method, to eliminate the above-said difficulty. The calculated examples show that the calculation using the new method in dynamic finite element analysis of high velocity impact is valid and stable, and the element stiffness can be somewhat reduced.
文摘In paper [5], we proposed the boundary expanding-contracting principle and the boundary expanding-contracting method (BECM). In this paper we make some complemental statements and detailed proofs about the principle.
文摘The boundary element method (KEM) which a used to solve the elastic problems has more advantages than other numerical methods. Especially, it can resolve rapidly varying internal stress and strain fields more accurately. However, it is of en fails in the region near the boundary because of the singularity of the solutions. Though we can increase the boundary meshes more and more, the solutions of stress on the boundary can't be given directly; which has obstructed the applications of the HEM to some extent.In this paper we proposed the boudary expanding-contracting principle and the boundary expanding-contracting method (BECM) based on the principle. With this method, not only the solutions in the region near or on the boundary can be obtained directly, but the iterative processes can also he used conveniently to improve the accuracy of the solutions.
