✍ Scribed by Georgios C. Georgiou; Lorraine G. Olson; William W. Schultz; Susan Sagan
No coin nor oath required. For personal study only.
Abrupt changes in boundary conditions in viscous flow problems give rise to stress singularities. Ordinary finite element methods account effectively for the global solution but perform poorly near the singularity. In this paper we develop singular finite elements, similar in principle to the crack tip elements used in fracture mechanics, to improve the solution accuracy in the vicinity of the singular point and to speed up the rate of convergence. These special elements surround the singular point, and the corresponding field shape functions embody the form of the singularity. Because the pressure is singular, there is no pressure node at the singular point. The method performs well when applied to the stick-slip problem and gives more accurate results than those from refined ordinary finite element meshes.
📜 SIMILAR VOLUMES
We further develop a new singular finite element method, the integrated singular basis function method (ISBFM), for the solution of Newtonian flow problems with stress singularities. The ISBFM is based on the direct subtraction of the leading local solution terms from the governing equations and bou
An analysis of some nonconforming approximations of the Stokes problem is presented. The approximations are based on a strain-pressure variational formulation. In particular, a convergence and stability result for a method recently proposed by Bathe and Pantuso is provided.